Liquidsoap scripting language reference

The Source / … categories contain all functions that return sources. The Input functions are those which build elementary sources (playing files, synthesizing sound, etc.). The Output functions are those which take a source and register it for being streamed to the outside (file, soundcard, audio server, etc.). The Visualization functions are experimental ones that let you visualize in real-time some aspects of the audio stream. The Sound Processing functions are those which basically work on the source as a continuous audio stream. They would typically be mixers of streams, audio effects or analysis. Finally, Track Processing functions are basically all others, often having a behaviour that depends on or affects the extra information that liquidsoap puts in streams: track limits and metadata.

Bool
Configuration
File
Getter
Interaction
Internet
Liquidsoap
List
Math
Metadata
Programming
Settings
Source / Audio processing
Source / Conversion
Source / FFmpeg filter
Source / Fade
Source / Input
Source / Liquidsoap
Source / MIDI processing
Source / Output
Source / Sound synthesis
Source / Testing
Source / Track processing
Source / Video processing
Source / Visualization
String
System
Time
Track / Audio processing
Track / Conversion
Track / FFmpeg filter
Track / Track processing
Track / Video processing

Bool

`!=`

Comparison of comparable values.

Type:

('a, 'a) -> bool where 'a is an orderable type

Arguments:

(unlabeled) (of type anything that is an orderable type)
(unlabeled) (of type anything that is an orderable type)

`<`

Comparison of comparable values.

Type:

('a, 'a) -> bool where 'a is an orderable type

Arguments:

(unlabeled) (of type anything that is an orderable type)
(unlabeled) (of type anything that is an orderable type)

`<=`

Comparison of comparable values.

Type:

('a, 'a) -> bool where 'a is an orderable type

Arguments:

(unlabeled) (of type anything that is an orderable type)
(unlabeled) (of type anything that is an orderable type)

`==`

Comparison of comparable values.

Type:

('a, 'a) -> bool where 'a is an orderable type

Arguments:

(unlabeled) (of type anything that is an orderable type)
(unlabeled) (of type anything that is an orderable type)

`>`

Comparison of comparable values.

Type:

('a, 'a) -> bool where 'a is an orderable type

Arguments:

(unlabeled) (of type anything that is an orderable type)
(unlabeled) (of type anything that is an orderable type)

`>=`

Comparison of comparable values.

Type:

('a, 'a) -> bool where 'a is an orderable type

Arguments:

(unlabeled) (of type anything that is an orderable type)
(unlabeled) (of type anything that is an orderable type)

`and`

Return the conjunction of its arguments

Type:

({bool}, {bool}) -> bool

Arguments:

(unlabeled) (of type {bool})
(unlabeled) (of type {bool})

`not`

Returns the negation of its argument.

Type:

(bool) -> bool

Arguments:

(unlabeled) (of type bool)

`or`

Return the disjunction of its arguments

Type:

({bool}, {bool}) -> bool

Arguments:

(unlabeled) (of type {bool})
(unlabeled) (of type {bool})

`random.bool`

Generate a random boolean.

Type:

() -> bool

Configuration

`configure.bindir`

Liquidsoap’s Internal script directory.

Type:

string

`configure.default_font`

Liquidsoap’s default font file.

Type:

string

`configure.libdir`

Liquidsoap’s library directory.

Type:

string

`configure.logdir`

Liquidsoap’s logging directory.

Type:

string

`configure.rundir`

Liquidsoap’s PID file directory.

Type:

string

`liquidsoap.build_config.architecture`

Build-time configuration value for architecture

Type:

string

`liquidsoap.build_config.git_sha`

Git sha used to compile liquidsoap.

Type:

string?

`liquidsoap.build_config.host`

Build-time configuration value for host

Type:

string

`liquidsoap.build_config.is_release`

Is this build a release build?

Type:

bool

`liquidsoap.build_config.is_snapshot`

Is this build a development snapshot?

Type:

bool

`liquidsoap.build_config.native_c_compiler`

Build-time configuration value for native_c_compiler

Type:

string

`liquidsoap.build_config.native_c_libraries`

Build-time configuration value for native_c_libraries

Type:

string

`liquidsoap.build_config.ocaml_version`

OCaml version used to compile liquidspap.

Type:

string

`liquidsoap.build_config.ocamlopt_cflags`

Build-time configuration value for ocamlopt_cflags

Type:

string

`liquidsoap.build_config.optionals.alsa`

Build-time configuration for alsa

Type:

bool

`liquidsoap.build_config.optionals.ao`

Build-time configuration for ao

Type:

bool

`liquidsoap.build_config.optionals.bjack`

Build-time configuration for bjack

Type:

bool

`liquidsoap.build_config.optionals.camlimages`

Build-time configuration for camlimages

Type:

bool

`liquidsoap.build_config.optionals.dssi`

Build-time configuration for dssi

Type:

bool

`liquidsoap.build_config.optionals.faad`

Build-time configuration for faad

Type:

bool

`liquidsoap.build_config.optionals.fdkaac`

Build-time configuration for fdkaac

Type:

bool

`liquidsoap.build_config.optionals.ffmpeg`

Build-time configuration for ffmpeg

Type:

bool

`liquidsoap.build_config.optionals.flac`

Build-time configuration for flac

Type:

bool

`liquidsoap.build_config.optionals.frei0r`

Build-time configuration for frei0r

Type:

bool

`liquidsoap.build_config.optionals.gd`

Build-time configuration for gd

Type:

bool

`liquidsoap.build_config.optionals.graphics`

Build-time configuration for graphics

Type:

bool

`liquidsoap.build_config.optionals.gstreamer`

Build-time configuration for gstreamer

Type:

bool

`liquidsoap.build_config.optionals.imagelib`

Build-time configuration for imagelib

Type:

bool

`liquidsoap.build_config.optionals.inotify`

Build-time configuration for inotify

Type:

bool

`liquidsoap.build_config.optionals.irc`

Build-time configuration for irc

Type:

bool

`liquidsoap.build_config.optionals.ladspa`

Build-time configuration for ladspa

Type:

bool

`liquidsoap.build_config.optionals.lame`

Build-time configuration for lame

Type:

bool

`liquidsoap.build_config.optionals.lastfm`

Build-time configuration for lastfm

Type:

bool

`liquidsoap.build_config.optionals.lilv`

Build-time configuration for lilv

Type:

bool

`liquidsoap.build_config.optionals.lo`

Build-time configuration for lo

Type:

bool

`liquidsoap.build_config.optionals.mad`

Build-time configuration for mad

Type:

bool

`liquidsoap.build_config.optionals.magic`

Build-time configuration for magic

Type:

bool

`liquidsoap.build_config.optionals.mem_usage`

Build-time configuration for mem_usage

Type:

bool

`liquidsoap.build_config.optionals.memtrace`

Build-time configuration for memtrace

Type:

bool

`liquidsoap.build_config.optionals.ogg`

Build-time configuration for ogg

Type:

bool

`liquidsoap.build_config.optionals.opus`

Build-time configuration for opus

Type:

bool

`liquidsoap.build_config.optionals.osc`

Build-time configuration for osc

Type:

bool

`liquidsoap.build_config.optionals.oss`

Build-time configuration for oss

Type:

bool

`liquidsoap.build_config.optionals.portaudio`

Build-time configuration for portaudio

Type:

bool

`liquidsoap.build_config.optionals.posix_time2`

Build-time configuration for posix_time2

Type:

bool

`liquidsoap.build_config.optionals.prometheus`

Build-time configuration for prometheus

Type:

bool

`liquidsoap.build_config.optionals.pulseaudio`

Build-time configuration for pulseaudio

Type:

bool

`liquidsoap.build_config.optionals.samplerate`

Build-time configuration for samplerate

Type:

bool

`liquidsoap.build_config.optionals.sdl`

Build-time configuration for sdl

Type:

bool

`liquidsoap.build_config.optionals.shine`

Build-time configuration for shine

Type:

bool

`liquidsoap.build_config.optionals.soundtouch`

Build-time configuration for soundtouch

Type:

bool

`liquidsoap.build_config.optionals.speex`

Build-time configuration for speex

Type:

bool

`liquidsoap.build_config.optionals.srt`

Build-time configuration for srt

Type:

bool

`liquidsoap.build_config.optionals.ssl`

Build-time configuration for ssl

Type:

bool

`liquidsoap.build_config.optionals.taglib`

Build-time configuration for taglib

Type:

bool

`liquidsoap.build_config.optionals.theora`

Build-time configuration for theora

Type:

bool

`liquidsoap.build_config.optionals.tls`

Build-time configuration for tls

Type:

bool

`liquidsoap.build_config.optionals.vorbis`

Build-time configuration for vorbis

Type:

bool

`liquidsoap.build_config.optionals.winsvc`

Build-time configuration for winsvc

Type:

bool

`liquidsoap.build_config.optionals.xmlplaylist`

Build-time configuration for xmlplaylist

Type:

bool

`liquidsoap.build_config.system`

Build-time configuration value for system

Type:

string

`liquidsoap.build_config.target`

Build-time configuration value for target

Type:

string

`liquidsoap.version`

Liquidsoap version string.

Type:

string

File

`file.contents`

Read the whole contents of a file.

Type:

(string) -> string

Arguments:

(unlabeled) (of type string)

`file.copy`

Copy a file. Arguments and implementation follows the POSIX cp command line specifications.

Type:

(?recursive : bool, ?force : bool, ?preserve : bool, string, string) -> unit

Arguments:

recursive (of type bool, which defaults to false): Copy file hierarchies.
force (of type bool, which defaults to false): If a file descriptor for a destination file cannot be obtained attempt to unlink the destination file and proceed.
preserve (of type bool, which defaults to false): Duplicate source files attributes in the destination file.
(unlabeled) (of type string): Source
(unlabeled) (of type string): Destination

`file.digest`

Return an MD5 digest for the given file.

Type:

(string) -> string

Arguments:

(unlabeled) (of type string)

`file.download`

Download file using a regular http.get request. Returns true on success.

Type:

(filename : string, ?timeout : float, string) -> bool

Arguments:

filename (of type string): Downloaded filename.
timeout (of type float, which defaults to 5.): Timeout in seconds
(unlabeled) (of type string)

`file.exists`

Returns true if the file or directory exists.

Type:

(string) -> bool

Arguments:

(unlabeled) (of type string)

`file.extension`

Returns a file’s extension.

Type:

(?dir_sep : string, ?leading_dot : bool, string) -> string

Arguments:

dir_sep (of type string, which defaults to "/"): Directory separator.
leading_dot (of type bool, which defaults to true): Return extension with a leading dot, e.g. .foo.
(unlabeled) (of type string)

`file.getter`

Getter to the contents of a file.

Type:

(string) -> () -> string

Arguments:

(unlabeled) (of type string): Name of the file from which the contents should be taken.

`file.getter.float`

Float getter from a file.

Type:

(?default : float, string) -> {float}

Arguments:

default (of type float, which defaults to 0.): Default value when the file contains invalid data.
(unlabeled) (of type string): Name of the file from which the contents should be taken.

`file.is_directory`

Returns true if the file exists and is a directory.

Type:

(string) -> bool

Arguments:

(unlabeled) (of type string)

`file.iterator`

Iterate over the contents of a file.

Type:

(string) -> () -> string?

Arguments:

(unlabeled) (of type string)

`file.lines`

Get the list of lines of a file.

Type:

(string) -> [string]

Arguments:

(unlabeled) (of type string)

`file.lines.iterator`

Iterate over the lines of a file.

Type:

(string) -> () -> string?

Arguments:

(unlabeled) (of type string)

`file.ls`

List all the files in a directory.

Type:

(?absolute : bool, ?recursive : bool, ?pattern : string?, ?sorted : bool,
 string) -> [string]

Arguments:

absolute (of type bool, which defaults to false): Whether to return absolute paths.
recursive (of type bool, which defaults to false): Whether to look recursively in subdirectories.
pattern (of type string?, which defaults to null): Pattern that the filenames should match (e.g. "*.mp3").
sorted (of type bool, which defaults to false): Return results in a sorted order.
(unlabeled) (of type string): Directory to look in.

`file.metadata`

Read metadata from a file.

Type:

(string, ?exclude : [string]) -> [string * string]

Arguments:

(unlabeled) (of type string): File from which the metadata should be read.
exclude (of type [string], which defaults to []): Decoders to exclude

`file.metadata.ffmpeg`

Read metadata from a file using the ffmpeg decoder.

Type:

(string) -> [string * string]

Arguments:

(unlabeled) (of type string): File from which the metadata should be read.

`file.metadata.flac`

Read metadata from a file using the flac decoder.

Type:

(string) -> [string * string]

Arguments:

(unlabeled) (of type string): File from which the metadata should be read.

`file.metadata.flac_native`

Read metadata from a file using the flac_native decoder.

Type:

(string) -> [string * string]

Arguments:

(unlabeled) (of type string): File from which the metadata should be read.

`file.metadata.id3`

Read metadata from a file using the id3 decoder.

Type:

(string) -> [string * string]

Arguments:

(unlabeled) (of type string): File from which the metadata should be read.

`file.metadata.id3v1`

Read metadata from a file using the id3v1 decoder.

Type:

(string) -> [string * string]

Arguments:

(unlabeled) (of type string): File from which the metadata should be read.

`file.metadata.id3v2`

Read metadata from a file using the id3v2 decoder.

Type:

(string) -> [string * string]

Arguments:

(unlabeled) (of type string): File from which the metadata should be read.

`file.metadata.image`

Read metadata from a file using the image decoder.

Type:

(string) -> [string * string]

Arguments:

(unlabeled) (of type string): File from which the metadata should be read.

`file.metadata.mp4`

Read metadata from a file using the mp4 decoder.

Type:

(string) -> [string * string]

Arguments:

(unlabeled) (of type string): File from which the metadata should be read.

`file.metadata.native`

Read metadata from a file using the native decoder.

Type:

(string) -> [string * string]

Arguments:

(unlabeled) (of type string): File from which the metadata should be read.

`file.metadata.ogg`

Read metadata from a file using the ogg decoder.

Type:

(string) -> [string * string]

Arguments:

(unlabeled) (of type string): File from which the metadata should be read.

`file.metadata.ogg_native`

Read metadata from a file using the ogg_native decoder.

Type:

(string) -> [string * string]

Arguments:

(unlabeled) (of type string): File from which the metadata should be read.

`file.metadata.taglib`

Read metadata from a file using the taglib decoder.

Type:

(string) -> [string * string]

Arguments:

(unlabeled) (of type string): File from which the metadata should be read.

`file.metadata.video-metadata`

Read metadata from a file using the video-metadata decoder.

Type:

(string) -> [string * string]

Arguments:

(unlabeled) (of type string): File from which the metadata should be read.

`file.mime`

Get a file’s mime type. Uses libmagic if enabled, otherwise try to get the value using the file binary. Returns null() if no value can be found.

Type:

(string) -> string?

Arguments:

(unlabeled) (of type string): The file to test

`file.mime.cli`

Get a file’s mime type by calling the file command line binary.

Type:

(string) -> string?

Arguments:

(unlabeled) (of type string)

`file.mime.libmagic`

Get the MIME type of a file, according to libmagic.

Type:

(string) -> string?

Arguments:

(unlabeled) (of type string)

`file.mkdir`

Create a directory.

Type:

(?perms : int, string) -> unit

Arguments:

perms (of type int, which defaults to 493): Default file rights if created (default is 0o755).
(unlabeled) (of type string)

`file.move`

Move a file

Type:

(?force : bool, string, string) -> unit

Arguments:

force (of type bool, which defaults to false): Do not prompt for confirmation if the destination path exists.
(unlabeled) (of type string): Source
(unlabeled) (of type string): Destination

`file.mtime`

Last modification time.

Type:

(string) -> float

Arguments:

(unlabeled) (of type string)

`file.open`

Open a file.

Type:

(?write : bool, ?create : bool?, ?append : bool, ?non_blocking : bool,
 ?perms : int, string) -> socket

Arguments:

write (of type bool, which defaults to false): Open file for writing
create (of type bool?, which defaults to null): Create if nonexistent. Default: false in read-only mode, true when writing.
append (of type bool, which defaults to false): Append data if file exists.
non_blocking (of type bool, which defaults to false): Open in non-blocking mode.
perms (of type int, which defaults to 420): Default file rights if created. Default: 0o644
(unlabeled) (of type string)

Methods:

close (of type () -> unit): Close the socket.
non_blocking (of type (bool) -> unit): Set the non-blocking flag on the socket
read (of type ((?timeout : float?) -> string) .{wait : (?timeout : float?, (() -> unit)) -> unit}): Read data from a socket. Reading is done when the function returns an empty string "".
type (of type string): Socket type
write (of type ((?timeout : float?, string) -> unit) .{wait : (?timeout : float?, (() -> unit)) -> unit}): Write data to a socket

`file.read`

Read the content of a file. Returns a function of type ()->string. File is done reading when function returns the empty string "".

Type:

(string) -> () -> string

Arguments:

(unlabeled) (of type string)

`file.remove`

Remove a file.

Type:

(string) -> unit

Arguments:

(unlabeled) (of type string)

`file.replaygain`

Compute the ReplayGain for a file (in dB).

Type:

(?id : string?, string) -> float?

Arguments:

id (of type string?, which defaults to null)
(unlabeled) (of type string): File name.

`file.rmdir`

Remove a directory and its content.

Type:

(string) -> unit

Arguments:

(unlabeled) (of type string)

`file.size`

File size in bytes.

Type:

(string) -> int

Arguments:

(unlabeled) (of type string)

`file.temp`

Return a fresh temporary filename. The temporary file is created empty, with permissions 0o600 (readable and writable only by the file owner).

Type:

(string, string) -> string

Arguments:

(unlabeled) (of type string): File prefix
(unlabeled) (of type string): File suffix

`file.temp_dir`

Return a fresh temporary directory name. The temporary directory is created empty, in the default tmp directory, with permissions 0o700 (readable, writable and listable only by the file owner).

Type:

(string, ?string) -> string

Arguments:

(unlabeled) (of type string): Directory name prefix.
(unlabeled) (of type string, which defaults to ""): Directory name suffix.

`file.umask`

Get the process’s file mode creation mask.

Type:

() -> int

`file.umask.set`

Set process’s file mode creation mask.

Type:

(int) -> unit

Arguments:

(unlabeled) (of type int)

`file.watch`

Call a function when a file is modified. Returns unwatch function in unwatch method.

Type:

(string, (() -> unit)) -> unit

Arguments:

(unlabeled) (of type string): File to watch.
(unlabeled) (of type () -> unit): Handler function.

Methods:

unwatch (of type () -> unit): Function to remove the watch on the file.

`file.which`

file.which("progname") looks for an executable named “progname” using directories from the PATH environment variable and returns “” if it could not find one.

Type:

(string) -> string?

Arguments:

(unlabeled) (of type string)

`file.write`

Write data to a file.

Type:

(data : {string?}, ?perms : int, ?append : bool, string) -> unit

Arguments:

data (of type {string?}): Data to write. If passing a callback () -> string?, the callback must return null or "" when it has finished sending all its data.
perms (of type int, which defaults to 420): Default file rights if created. Default: 0o644.
append (of type bool, which defaults to false): Append data if file exists.
(unlabeled) (of type string): Path to write to

`file.write.stream`

Stream data to a file. Returns a callback to write to the file. Execute with null or "" to signify the end of the writing operation.

Type:

(?perms : int, ?append : bool, string) -> (string?) -> unit

Arguments:

perms (of type int, which defaults to 420): Default file rights if created. Default: 0o644.
append (of type bool, which defaults to false): Append data if file exists.
(unlabeled) (of type string): Path to write to

`medialib`

A library to store the metadata of files in given folders and query them. This is useful to generate playlists based on metadata.

Type:

(?id : string?, ?persistency : string?, ?refresh : float?,
 ?standardize : (([string * string]) -> [string * string]),
 ?initial_progress : bool, ?directories : [string], ?string?) -> unit

Arguments:

id (of type string?, which defaults to null)
persistency (of type string?, which defaults to null): Store the database in given file, which is reuse to populate the database on next run.
refresh (of type float?, which defaults to null): Scan directories for new files every given number of seconds (by default the database is never updated).
standardize (of type ([string * string]) -> [string * string], which defaults to <fun>): Function mapped on metadata when indexing. It can be used to change the field names to standard ones, pretreat data, etc.
initial_progress (of type bool, which defaults to true): Show progress of library being indexed at startup.
directories (of type [string], which defaults to []): Directories to look for files in.
(unlabeled) (of type string?, which defaults to null): Directory to look for files in.

Methods:

add_directory (of type (string) -> unit): Add a new directory which should be scanned.
clear (of type () -> unit): Remove all known metadata.
find (of type (?case_sensitive : bool, ?artist : string?, ?artist_contains : string?, ?artist_matches : string?, ?album : string?, ?genre : string?, ?title : string?, ?title_contains : string?, ?filename : string?, ?filename_contains : string?, ?filename_matches : string?, ?year : int?, ?year_ge : int?, ?year_lt : int?, ?bpm : int?, ?bpm_ge : int?, ?int?, ?predicate : (([string * string]) -> bool)) -> [string]): Find files according to conditions on metadata.
refresh (of type () -> unit): Update metadatas and look for new files.

`path.basename`

Get the base name of a path, i.e. the name of the file without the full path. For instance file.basename("/tmp/folder/bla.mp3") returns "bla.mp3".

Type:

(string) -> string

Arguments:

(unlabeled) (of type string)

`path.concat`

Concatenate two paths, using the appropriate directory separator.

Type:

(string, string) -> string

Arguments:

(unlabeled) (of type string)
(unlabeled) (of type string)

`path.dirname`

Get the directory name of a path.

Type:

(string) -> string

Arguments:

(unlabeled) (of type string)

`path.home.unrelate`

Expand path that start with ‘~’ with the current home directory.

Type:

(string) -> string

Arguments:

(unlabeled) (of type string)

`path.remove_extension`

Remove the file extension from a path.

Type:

(string) -> string

Arguments:

(unlabeled) (of type string)

`playlist.files`

Retrieve the list of files contained in a playlist.

Type:

(?id : string?, ?mime_type : string?, ?timeout : float, string) -> [string]

Arguments:

id (of type string?, which defaults to null)
mime_type (of type string?, which defaults to null): Default MIME type for the playlist. null means automatic detection.
timeout (of type float, which defaults to 20.): Timeout for resolving the playlist
(unlabeled) (of type string): Path to the playlist

`socket.unix.client`

Open a named UNIX socket and connect as a client.

Type:

(?non_blocking : bool, string) -> socket

Arguments:

non_blocking (of type bool, which defaults to false): Open in non-blocking mode.
(unlabeled) (of type string)

Methods:

close (of type () -> unit):
read (of type ((?timeout : float?) -> string) .{wait : (?timeout : float?, (() -> unit)) -> unit}):
type (of type string):
write (of type ((?timeout : float?, string) -> unit) .{wait : (?timeout : float?, (() -> unit)) -> unit}):

`socket.unix.listen`

Open a named socket and wait for a client to connect

Type:

(?non_blocking : bool, string) -> socket

Arguments:

non_blocking (of type bool, which defaults to false): Open in non-blocking mode.
(unlabeled) (of type string)

Methods:

close (of type () -> unit):
read (of type ((?timeout : float?) -> string) .{wait : (?timeout : float?, (() -> unit)) -> unit}):
type (of type string):
write (of type ((?timeout : float?, string) -> unit) .{wait : (?timeout : float?, (() -> unit)) -> unit}):

Getter

`getter`

Create a getter.

Type:

({'a}) -> {'a}

Arguments:

(unlabeled) (of type {'a}): Value from which the getter should be created.

`getter.case`

Return a value depending on whether the getter is constant or not.

Type:

({'a}, (('a) -> 'b), (((() -> 'a)) -> 'b)) -> 'b

Arguments:

(unlabeled) (of type {'a}): Getter to inspect.
(unlabeled) (of type ('a) -> 'b)
(unlabeled) (of type ((() -> 'a)) -> 'b)

`getter.changes`

Detect whether the value of the getter changes.

Type:

({'a}) -> () -> bool where 'a is an orderable type

Arguments:

(unlabeled) (of type {'a} where 'a is an orderable type)

`getter.float_of_int`

Convert an int getter to a float getter.

Type:

({int}) -> {float}

Arguments:

(unlabeled) (of type {int})

`getter.function`

Construct a function returning the value of a getter.

Type:

({'a}) -> () -> 'a

Arguments:

(unlabeled) (of type {'a})

`getter.get`

Get the value of a getter.

Type:

({'a}) -> 'a

Arguments:

(unlabeled) (of type {'a})

`getter.int_of_float`

Convert a float getter to a int getter.

Type:

({float}) -> {int}

Arguments:

(unlabeled) (of type {float})

`getter.is_constant`

Determine if a getter is a constant.

Type:

({'a}) -> bool

Arguments:

(unlabeled) (of type {'a})

`getter.map`

Apply a function on a getter.

Type:

((('a) -> 'b), {'a}) -> {'b}

Arguments:

(unlabeled) (of type ('a) -> 'b): Function to apply.
(unlabeled) (of type {'a})

`getter.map.memoize`

Apply a function on a getter. If the input value has not changed compared to last call, the previous result is returned without computing the function again.

Type:

((('a) -> 'b), {'a}) -> {'b} where 'a is an orderable type

Arguments:

(unlabeled) (of type ('a) -> 'b where 'a is an orderable type): Function to apply.
(unlabeled) (of type {'a} where 'a is an orderable type)

`getter.merge`

Give the latest value among two getters.

Type:

({'a}, {'a}) -> () -> 'a where 'a is an orderable type

Arguments:

(unlabeled) (of type {'a} where 'a is an orderable type)
(unlabeled) (of type {'a} where 'a is an orderable type)

`getter.on_change`

Execute a function when the value of the getter changes.

Type:

((('a) -> unit), {'a}) -> () -> 'a where 'a is an orderable type

Arguments:

(unlabeled) (of type ('a) -> unit where 'a is an orderable type)
(unlabeled) (of type {'a} where 'a is an orderable type)

Interaction

`audioscrobbler.nowplaying`

Submit a now playing song using the audioscrobbler protocol.

Type:

(user : string, password : string, ?host : string, ?port : int,
 ?length : bool, [string * string]) -> unit

Arguments:

user (of type string)
password (of type string)
host (of type string, which defaults to "post.audioscrobbler.com"): Host for audioscrobbling submissions.
port (of type int, which defaults to 80): Port for audioscrobbling submissions.
length (of type bool, which defaults to false): Try to submit length information. This operation can be CPU intensive. Value forced to true when used with the “user” source type.
(unlabeled) (of type [string * string])

`audioscrobbler.submit`

Submit a played song using the audioscrobbler protocol.

Type:

(?source : string, user : string, password : string, ?host : string,
 ?port : int, ?length : bool, [string * string]) -> unit

Arguments:

source (of type string, which defaults to "broadcast"): Source for tracks. Should be one of: “broadcast”, “user”, “recommendation” or “unknown”. Since liquidsoap is intended for radio broadcasting, this is the default. Sources other than user don’t need duration to be set.
user (of type string)
password (of type string)
host (of type string, which defaults to "post.audioscrobbler.com"): Host for audioscrobbling submissions.
port (of type int, which defaults to 80): Port for audioscrobbling submissions.
length (of type bool, which defaults to false): Try to submit length information. This operation can be CPU intensive. Value forced to true when used with the “user” source type.
(unlabeled) (of type [string * string])

`icy.update_metadata`

Update metata on an icecast mountpoint using the ICY protocol.

Type:

(?host : string, ?port : int, ?user : string, ?transport : http_transport,
 ?password : string, ?mount : string, ?icy_id : int, ?protocol : string,
 ?encoding : string?, ?headers : [string * string], [string * string]) ->
unit

Arguments:

host (of type string, which defaults to "localhost")
port (of type int, which defaults to 8000)
user (of type string, which defaults to "source")
transport (of type http_transport, which defaults to <unix_transport>): Http transport. Use http.transport.ssl or http.transport.secure_transport, when available, to enable HTTPS output
password (of type string, which defaults to "hackme")
mount (of type string, which defaults to ""): Source mount point. Mandatory when streaming to icecast.
icy_id (of type int, which defaults to 1): Shoutcast source ID. Only supported by Shoutcast v2.
protocol (of type string, which defaults to "http"): Protocol to use. One of: “icy”, “http” or “https”
encoding (of type string?, which defaults to null): Encoding used to send metadata, default (UTF-8) if null.
headers (of type [string * string], which defaults to [("User-Agent", "Liquidsoap/2.2.0 (Unix; OCaml 4.14.1)")]): Additional headers.
(unlabeled) (of type [string * string])

`osc.bool`

Read from an OSC path.

Type:

(string, bool) -> () -> bool

Arguments:

(unlabeled) (of type string): OSC path.
(unlabeled) (of type bool): Initial value.

`osc.float`

Read from an OSC path.

Type:

(string, float) -> () -> float

Arguments:

(unlabeled) (of type string): OSC path.
(unlabeled) (of type float): Initial value.

`osc.float_pair`

Read from an OSC path.

Type:

(string, (float * float)) -> () -> float * float

Arguments:

(unlabeled) (of type string): OSC path.
(unlabeled) (of type float * float): Initial value.

`osc.int`

Read from an OSC path.

Type:

(string, int) -> () -> int

Arguments:

(unlabeled) (of type string): OSC path.
(unlabeled) (of type int): Initial value.

`osc.int_pair`

Read from an OSC path.

Type:

(string, (int * int)) -> () -> int * int

Arguments:

(unlabeled) (of type string): OSC path.
(unlabeled) (of type int * int): Initial value.

`osc.native.float`

Read from an OSC path.

Type:

(string, float) -> () -> float

Arguments:

(unlabeled) (of type string): OSC path.
(unlabeled) (of type float): Initial value.

`osc.native.float_pair`

Read from an OSC path.

Type:

(string, (float * float)) -> () -> float * float

Arguments:

(unlabeled) (of type string): OSC path.
(unlabeled) (of type float * float): Initial value.

`osc.native.int`

Read from an OSC path.

Type:

(string, int) -> () -> int

Arguments:

(unlabeled) (of type string): OSC path.
(unlabeled) (of type int): Initial value.

`osc.native.int_pair`

Read from an OSC path.

Type:

(string, (int * int)) -> () -> int * int

Arguments:

(unlabeled) (of type string): OSC path.
(unlabeled) (of type int * int): Initial value.

`osc.native.on_float`

Type:

(string, ((float) -> unit)) -> unit

Arguments:

(unlabeled) (of type string): OSC path.
(unlabeled) (of type (float) -> unit): Callback function.

`osc.native.on_float_pair`

Type:

(string, (((float * float)) -> unit)) -> unit

Arguments:

(unlabeled) (of type string): OSC path.
(unlabeled) (of type ((float * float)) -> unit): Callback function.

`osc.native.on_int`

Type:

(string, ((int) -> unit)) -> unit

Arguments:

(unlabeled) (of type string): OSC path.
(unlabeled) (of type (int) -> unit): Callback function.

`osc.native.on_int_pair`

Type:

(string, (((int * int)) -> unit)) -> unit

Arguments:

(unlabeled) (of type string): OSC path.
(unlabeled) (of type ((int * int)) -> unit): Callback function.

`osc.native.on_string`

Type:

(string, ((string) -> unit)) -> unit

Arguments:

(unlabeled) (of type string): OSC path.
(unlabeled) (of type (string) -> unit): Callback function.

`osc.native.on_string_pair`

Type:

(string, (((string * string)) -> unit)) -> unit

Arguments:

(unlabeled) (of type string): OSC path.
(unlabeled) (of type ((string * string)) -> unit): Callback function.

`osc.native.send_float`

Send a value to an OSC client.

Type:

(host : string, port : int, string, float) -> unit

Arguments:

host (of type string): OSC client address.
port (of type int): OSC client port.
(unlabeled) (of type string): OSC path.
(unlabeled) (of type float): Value to send.

`osc.native.send_float_pair`

Send a value to an OSC client.

Type:

(host : string, port : int, string, (float * float)) -> unit

Arguments:

host (of type string): OSC client address.
port (of type int): OSC client port.
(unlabeled) (of type string): OSC path.
(unlabeled) (of type float * float): Value to send.

`osc.native.send_int`

Send a value to an OSC client.

Type:

(host : string, port : int, string, int) -> unit

Arguments:

host (of type string): OSC client address.
port (of type int): OSC client port.
(unlabeled) (of type string): OSC path.
(unlabeled) (of type int): Value to send.

`osc.native.send_int_pair`

Send a value to an OSC client.

Type:

(host : string, port : int, string, (int * int)) -> unit

Arguments:

host (of type string): OSC client address.
port (of type int): OSC client port.
(unlabeled) (of type string): OSC path.
(unlabeled) (of type int * int): Value to send.

`osc.native.send_string`

Send a value to an OSC client.

Type:

(host : string, port : int, string, string) -> unit

Arguments:

host (of type string): OSC client address.
port (of type int): OSC client port.
(unlabeled) (of type string): OSC path.
(unlabeled) (of type string): Value to send.

`osc.native.send_string_pair`

Send a value to an OSC client.

Type:

(host : string, port : int, string, (string * string)) -> unit

Arguments:

host (of type string): OSC client address.
port (of type int): OSC client port.
(unlabeled) (of type string): OSC path.
(unlabeled) (of type string * string): Value to send.

`osc.native.string`

Read from an OSC path.

Type:

(string, string) -> () -> string

Arguments:

(unlabeled) (of type string): OSC path.
(unlabeled) (of type string): Initial value.

`osc.native.string_pair`

Read from an OSC path.

Type:

(string, (string * string)) -> () -> string * string

Arguments:

(unlabeled) (of type string): OSC path.
(unlabeled) (of type string * string): Initial value.

`osc.on_bool`

Type:

(string, ((bool) -> unit)) -> unit

Arguments:

(unlabeled) (of type string): OSC path.
(unlabeled) (of type (bool) -> unit): Callback function.

`osc.on_float`

Type:

(string, ((float) -> unit)) -> unit

Arguments:

(unlabeled) (of type string): OSC path.
(unlabeled) (of type (float) -> unit): Callback function.

`osc.on_float_pair`

Type:

(string, (((float * float)) -> unit)) -> unit

Arguments:

(unlabeled) (of type string): OSC path.
(unlabeled) (of type ((float * float)) -> unit): Callback function.

`osc.on_int`

Type:

(string, ((int) -> unit)) -> unit

Arguments:

(unlabeled) (of type string): OSC path.
(unlabeled) (of type (int) -> unit): Callback function.

`osc.on_int_pair`

Type:

(string, (((int * int)) -> unit)) -> unit

Arguments:

(unlabeled) (of type string): OSC path.
(unlabeled) (of type ((int * int)) -> unit): Callback function.

`osc.on_string`

Type:

(string, ((string) -> unit)) -> unit

Arguments:

(unlabeled) (of type string): OSC path.
(unlabeled) (of type (string) -> unit): Callback function.

`osc.on_string_pair`

Type:

(string, (((string * string)) -> unit)) -> unit

Arguments:

(unlabeled) (of type string): OSC path.
(unlabeled) (of type ((string * string)) -> unit): Callback function.

`osc.send_bool`

Send a value to an OSC client.

Type:

(host : string, port : int, string, bool) -> unit

Arguments:

host (of type string): OSC client address.
port (of type int): OSC client port.
(unlabeled) (of type string): OSC path.
(unlabeled) (of type bool): Value to send.

`osc.send_float`

Send a value to an OSC client.

Type:

(host : string, port : int, string, float) -> unit

Arguments:

host (of type string): OSC client address.
port (of type int): OSC client port.
(unlabeled) (of type string): OSC path.
(unlabeled) (of type float): Value to send.

`osc.send_float_pair`

Send a value to an OSC client.

Type:

(host : string, port : int, string, (float * float)) -> unit

Arguments:

host (of type string): OSC client address.
port (of type int): OSC client port.
(unlabeled) (of type string): OSC path.
(unlabeled) (of type float * float): Value to send.

`osc.send_int`

Send a value to an OSC client.

Type:

(host : string, port : int, string, int) -> unit

Arguments:

host (of type string): OSC client address.
port (of type int): OSC client port.
(unlabeled) (of type string): OSC path.
(unlabeled) (of type int): Value to send.

`osc.send_int_pair`

Send a value to an OSC client.

Type:

(host : string, port : int, string, (int * int)) -> unit

Arguments:

host (of type string): OSC client address.
port (of type int): OSC client port.
(unlabeled) (of type string): OSC path.
(unlabeled) (of type int * int): Value to send.

`osc.send_string`

Send a value to an OSC client.

Type:

(host : string, port : int, string, string) -> unit

Arguments:

host (of type string): OSC client address.
port (of type int): OSC client port.
(unlabeled) (of type string): OSC path.
(unlabeled) (of type string): Value to send.

`osc.send_string_pair`

Send a value to an OSC client.

Type:

(host : string, port : int, string, (string * string)) -> unit

Arguments:

host (of type string): OSC client address.
port (of type int): OSC client port.
(unlabeled) (of type string): OSC path.
(unlabeled) (of type string * string): Value to send.

`osc.string`

Read from an OSC path.

Type:

(string, string) -> () -> string

Arguments:

(unlabeled) (of type string): OSC path.
(unlabeled) (of type string): Initial value.

`osc.string_pair`

Read from an OSC path.

Type:

(string, (string * string)) -> () -> string * string

Arguments:

(unlabeled) (of type string): OSC path.
(unlabeled) (of type string * string): Initial value.

`prometheus.counter`

Type:

(help : string, ?namespace : string, ?subsystem : string, labels : [string],
 string) -> (label_values : [string]) -> (float) -> unit

Arguments:

help (of type string): Help of the metric
namespace (of type string, which defaults to ""): namespace of the metric
subsystem (of type string, which defaults to ""): subsystem of the metric
labels (of type [string]): labels for the metric
(unlabeled) (of type string): Name of the metric

`prometheus.gauge`

Type:

(help : string, ?namespace : string, ?subsystem : string, labels : [string],
 string) -> (label_values : [string]) -> (float) -> unit

Arguments:

help (of type string): Help of the metric
namespace (of type string, which defaults to ""): namespace of the metric
subsystem (of type string, which defaults to ""): subsystem of the metric
labels (of type [string]): labels for the metric
(unlabeled) (of type string): Name of the metric

`prometheus.summary`

Type:

(help : string, ?namespace : string, ?subsystem : string, labels : [string],
 string) -> (label_values : [string]) -> (float) -> unit

Arguments:

help (of type string): Help of the metric
namespace (of type string, which defaults to ""): namespace of the metric
subsystem (of type string, which defaults to ""): subsystem of the metric
labels (of type [string]): labels for the metric
(unlabeled) (of type string): Name of the metric

`server.register`

Type:

(?namespace : string?, ?description : string, ?usage : string?, string,
 ((string) -> string)) -> unit

Arguments:

namespace (of type string?, which defaults to null): Used to group multiple commands for the same functionality. If specified, the command will be named namespace.command.
description (of type string, which defaults to "No documentation available."): A description of your command.
usage (of type string?, which defaults to null): Description of how the command should be used.
(unlabeled) (of type string): Name of the command.
(unlabeled) (of type (string) -> string): Function called when the command is executed. It takes as argument the argument passed on the commandline and returns the message which will be printed on the commandline.

`server.telnet`

Enable telnet server.

Type:

(?port : int) -> unit

Arguments:

port (of type int, which defaults to 1234): Port on which we should listen.

Internet

`harbor.http.middleware.register`

Type:

(((
   {
     body : (?timeout : float) -> string,
     data : (?timeout : float) -> string,
     headers : [string * string],
     http_version : string,
     method : string,
     path : string,
     query : [string * string]
   }, (() -> string)
   .{
     content_type : ((string?) -> unit)
     .{current : () -> string?
     },
     data : (({string}) -> unit)
     .{current : () -> {string}
     },
     header : (string, string) -> unit,
     headers : (([string * string]) -> unit)
     .{current : () -> [string * string]
     },
     html : ({string}) -> unit,
     http_version : ((string) -> unit)
     .{current : () -> string
     },
     json : ('C) -> unit,
     multipart_form : (?boundary : string?,
                       [
                        {
                          attributes : [string * string],
                          contents : {string},
                          headers : ['A * 'B],
                          name : string
                        }]) -> unit,
     redirect : (?status_code : int, string) -> unit,
     send_status : (socket
                    .{
                      close : () -> unit,
                      non_blocking : (bool) -> unit,
                      read : ((?timeout : float?) -> string)
                      .{wait : (?timeout : float?, (() -> unit)) -> unit
                      },
                      type : string,
                      write : (string) -> unit
                    }) -> unit,
     status_code : ((int) -> unit)
     .{current : () -> int
     },
     status_message : ((string?) -> unit)
     .{current : () -> string?
     },
     status_sent : () -> bool
   },
   ((
     {
       body : (?timeout : float) -> string,
       data : (?timeout : float) -> string,
       headers : [string * string],
       http_version : string,
       method : string,
       path : string,
       query : [string * string]
     }, (() -> string)
     .{
       content_type : ((string?) -> unit)
       .{current : () -> string?
       },
       data : (({string}) -> unit)
       .{current : () -> {string}
       },
       header : (string, string) -> unit,
       headers : (([string * string]) -> unit)
       .{current : () -> [string * string]
       },
       html : ({string}) -> unit,
       http_version : ((string) -> unit)
       .{current : () -> string
       },
       json : ('C) -> unit,
       multipart_form : (?boundary : string?,
                         [
                          {
                            attributes : [string * string],
                            contents : {string},
                            headers : ['A * 'B],
                            name : string
                          }]) -> unit,
       redirect : (?status_code : int, string) -> unit,
       send_status : (socket
                      .{
                        close : () -> unit,
                        non_blocking : (bool) -> unit,
                        read : ((?timeout : float?) -> string)
                        .{wait : (?timeout : float?, (() -> unit)) -> unit
                        },
                        type : string,
                        write : (string) -> unit
                      }) -> unit,
       status_code : ((int) -> unit)
       .{current : () -> int
       },
       status_message : ((string?) -> unit)
       .{current : () -> string?
       },
       status_sent : () -> bool
     }) -> unit)) -> unit)) -> unit

Arguments:

(unlabeled) (of type ( { body : (?timeout : float) -> string, data : (?timeout : float) -> string, headers : [string * string], http_version : string, method : string, path : string, query : [string * string] }, (() -> string) .{ content_type : ((string?) -> unit) .{current : () -> string? }, data : (({string}) -> unit) .{current : () -> {string} }, header : (string, string) -> unit, headers : (([string * string]) -> unit) .{current : () -> [string * string] }, html : ({string}) -> unit, http_version : ((string) -> unit) .{current : () -> string }, json : ('C) -> unit, multipart_form : (?boundary : string?, [ { attributes : [string * string], contents : {string}, headers : ['A * 'B], name : string }]) -> unit, redirect : (?status_code : int, string) -> unit, send_status : (socket .{ close : () -> unit, non_blocking : (bool) -> unit, read : ((?timeout : float?) -> string) .{wait : (?timeout : float?, (() -> unit)) -> unit }, type : string, write : (string) -> unit }) -> unit, status_code : ((int) -> unit) .{current : () -> int }, status_message : ((string?) -> unit) .{current : () -> string? }, status_sent : () -> bool }, (( { body : (?timeout : float) -> string, data : (?timeout : float) -> string, headers : [string * string], http_version : string, method : string, path : string, query : [string * string] }, (() -> string) .{ content_type : ((string?) -> unit) .{current : () -> string? }, data : (({string}) -> unit) .{current : () -> {string} }, header : (string, string) -> unit, headers : (([string * string]) -> unit) .{current : () -> [string * string] }, html : ({string}) -> unit, http_version : ((string) -> unit) .{current : () -> string }, json : ('C) -> unit, multipart_form : (?boundary : string?, [ { attributes : [string * string], contents : {string}, headers : ['A * 'B], name : string }]) -> unit, redirect : (?status_code : int, string) -> unit, send_status : (socket .{ close : () -> unit, non_blocking : (bool) -> unit, read : ((?timeout : float?) -> string) .{wait : (?timeout : float?, (() -> unit)) -> unit }, type : string, write : (string) -> unit }) -> unit, status_code : ((int) -> unit) .{current : () -> int }, status_message : ((string?) -> unit) .{current : () -> string? }, status_sent : () -> bool }) -> unit)) -> unit)

`harbor.http.register`

Register a HTTP handler on the harbor. The handler function receives as argument the full requested information and returns the answer sent to the client, including HTTP headers. This function registers exact path matches, i.e. "/users", "/index.hml" as well as fragment matches, i.e. "/user/:id", "/users/:id/collabs/:cid", etc. If you need more advanced matching, use harbor.http.register.regexp to match regular expressions. Paths are resolved in the order they are declared and can override default harbor paths such as metadata handlers. The handler receives the request details as a record and a response handler. Matched fragments are reported as part of the response query parameter. The response handler can be used to fill up details about the http response, which will be converted into a plain HTTP response string after the handler returns.

Type:

(?port : int, ?transport : http_transport
 .{default_port : int, name : string, protocol : string}, ?method : string,
 string,
 ((
   {
     body : (?timeout : float) -> string,
     data : (?timeout : float) -> string,
     headers : [string * string],
     http_version : string,
     method : string,
     path : string,
     query : [string * string]
   }, (() -> string)
   .{
     content_type : ((string?) -> unit)
     .{current : () -> string?
     },
     data : (({string}) -> unit)
     .{current : () -> {string}
     },
     header : (string, string) -> unit,
     headers : (([string * string]) -> unit)
     .{current : () -> [string * string]
     },
     html : ({string}) -> unit,
     http_version : ((string) -> unit)
     .{current : () -> string
     },
     json : ('C) -> unit,
     multipart_form : (?boundary : string?,
                       [
                        {
                          attributes : [string * string],
                          contents : {string},
                          headers : ['A * 'B],
                          name : string
                        }]) -> unit,
     redirect : (?status_code : int, string) -> unit,
     send_status : (socket
                    .{
                      close : () -> unit,
                      non_blocking : (bool) -> unit,
                      read : ((?timeout : float?) -> string)
                      .{wait : (?timeout : float?, (() -> unit)) -> unit
                      },
                      type : string,
                      write : (string) -> unit
                    }) -> unit,
     status_code : ((int) -> unit)
     .{current : () -> int
     },
     status_message : ((string?) -> unit)
     .{current : () -> string?
     },
     status_sent : () -> bool
   }) -> unit)) -> unit

Arguments:

port (of type int, which defaults to 8000): Port to serve.
transport (of type http_transport.{default_port : int, name : string, protocol : string}, which defaults to <unix_transport>.{name="unix", protocol="http", default_port=80}): Http transport. Use http.transport.ssl or http.transport.secure_transport, when available, to enable HTTPS output
method (of type string, which defaults to "GET"): Accepted method (“GET” / “POST” / “PUT” / “DELETE” / “HEAD” / “OPTIONS”).
(unlabeled) (of type string)
(unlabeled) (of type ( { body : (?timeout : float) -> string, data : (?timeout : float) -> string, headers : [string * string], http_version : string, method : string, path : string, query : [string * string] }, (() -> string) .{ content_type : ((string?) -> unit) .{current : () -> string? }, data : (({string}) -> unit) .{current : () -> {string} }, header : (string, string) -> unit, headers : (([string * string]) -> unit) .{current : () -> [string * string] }, html : ({string}) -> unit, http_version : ((string) -> unit) .{current : () -> string }, json : ('C) -> unit, multipart_form : (?boundary : string?, [ { attributes : [string * string], contents : {string}, headers : ['A * 'B], name : string }]) -> unit, redirect : (?status_code : int, string) -> unit, send_status : (socket .{ close : () -> unit, non_blocking : (bool) -> unit, read : ((?timeout : float?) -> string) .{wait : (?timeout : float?, (() -> unit)) -> unit }, type : string, write : (string) -> unit }) -> unit, status_code : ((int) -> unit) .{current : () -> int }, status_message : ((string?) -> unit) .{current : () -> string? }, status_sent : () -> bool }) -> unit)

`harbor.http.register.simple`

Register a HTTP handler on the harbor. This function offers a simple API, suitable for quick implementation of HTTP handlers. See harbor.http.register for a node/express like alternative API.

Type:

(?port : int, ?transport : http_transport
 .{default_port : int, name : string, protocol : string}, ?method : string,
 string,
 ((
   {
     body : (?timeout : float) -> string,
     data : (?timeout : float) -> string,
     headers : [string * string],
     http_version : string,
     method : string,
     path : string,
     query : [string * string],
     socket : socket
     .{
       close : () -> unit,
       non_blocking : (bool) -> unit,
       read : ((?timeout : float?) -> string)
       .{wait : (?timeout : float?, (() -> unit)) -> unit
       },
       type : string,
       write : ((?timeout : float?, string) -> unit)
       .{wait : (?timeout : float?, (() -> unit)) -> unit
       }
     }
   }) -> {string}?)) -> unit

Arguments:

port (of type int, which defaults to 8000): Port to serve.
transport (of type http_transport.{default_port : int, name : string, protocol : string}, which defaults to <unix_transport>.{name="unix", protocol="http", default_port=80}): Http transport. Use http.transport.ssl or http.transport.secure_transport, when available, to enable HTTPS output
method (of type string, which defaults to "GET"): Accepted method (“GET” / “POST” / “PUT” / “DELETE” / “HEAD” / “OPTIONS”).
(unlabeled) (of type string)
(unlabeled) (of type ( { body : (?timeout : float) -> string, data : (?timeout : float) -> string, headers : [string * string], http_version : string, method : string, path : string, query : [string * string], socket : socket .{ close : () -> unit, non_blocking : (bool) -> unit, read : ((?timeout : float?) -> string) .{wait : (?timeout : float?, (() -> unit)) -> unit }, type : string, write : ((?timeout : float?, string) -> unit) .{wait : (?timeout : float?, (() -> unit)) -> unit } } }) -> {string}?)

`harbor.http.register.simple.regexp`

Register a HTTP handler on the harbor with a generic regexp path. This function offers a simple API, suitable for quick implementation of HTTP handlers. See harbor.http.register for a node/express like alternative API.

Type:

(?port : int, ?transport : http_transport
 .{default_port : int, name : string, protocol : string}, ?method : string,
 regexp,
 ((
   {
     data : (?timeout : float) -> string,
     headers : [string * string],
     http_version : string,
     method : string,
     path : string,
     query : [string * string],
     socket : socket
     .{
       close : () -> unit,
       non_blocking : (bool) -> unit,
       read : ((?timeout : float?) -> string)
       .{wait : (?timeout : float?, (() -> unit)) -> unit
       },
       type : string,
       write : ((?timeout : float?, string) -> unit)
       .{wait : (?timeout : float?, (() -> unit)) -> unit
       }
     }
   }) -> {string}?)) -> unit

Arguments:

port (of type int, which defaults to 8000): Port to serve.
transport (of type http_transport.{default_port : int, name : string, protocol : string}, which defaults to <unix_transport>.{name="unix", protocol="http", default_port=80}): Http transport. Use http.transport.ssl or http.transport.secure_transport, when available, to enable HTTPS output
method (of type string, which defaults to "GET"): Accepted method (“GET” / “POST” / “PUT” / “DELETE” / “HEAD” / “OPTIONS”).
(unlabeled) (of type regexp)
(unlabeled) (of type ( { data : (?timeout : float) -> string, headers : [string * string], http_version : string, method : string, path : string, query : [string * string], socket : socket .{ close : () -> unit, non_blocking : (bool) -> unit, read : ((?timeout : float?) -> string) .{wait : (?timeout : float?, (() -> unit)) -> unit }, type : string, write : ((?timeout : float?, string) -> unit) .{wait : (?timeout : float?, (() -> unit)) -> unit } } }) -> {string}?)

`harbor.http.static`

Serve a static path.

Type:

(?transport : http_transport
 .{default_port : int, name : string, protocol : string}, ?port : int,
 ?path : string, ?browse : bool, ?content_type : ((string) -> string?),
 ?headers : [string * string], string) -> unit

Arguments:

transport (of type http_transport.{default_port : int, name : string, protocol : string}, which defaults to <unix_transport>.{default_port=80, protocol="http", name="unix"}): Http transport. Use http.transport.ssl or http.transport.secure_transport`, when available, to enable HTTPS output
port (of type int, which defaults to 8000): Port for incoming harbor (http) connections.
path (of type string, which defaults to "/"): Base path.
browse (of type bool, which defaults to false): List files in directories.
content_type (of type (string) -> string?, which defaults to <fun>.{libmagic=<fun>, cli=<fun>}): Callback to specify Content-Type on a per file basis. Default: file.mime if compiled or file CLI if present.
headers (of type [string * string], which defaults to [("Access-Control-Allow-Origin", "*")]): Default response headers.
(unlabeled) (of type string): Local path to be served.

`harbor.remove`

Remove a registered handler on the harbor.

Type:

(?port : int, ?method : string, regexp) -> unit

Arguments:

port (of type int, which defaults to 8000): Port to serve.
method (of type string, which defaults to "GET"): Method served.
(unlabeled) (of type regexp): URI served.

`host.of_internet_address`

Find a host by internet address

Type:

(internet_address) -> 
{
  addresses : [internet_address.{is_ipv6 : bool, to_string : () -> string}],
  aliases : [string],
  domain : socket_domain,
  name : string}?

Arguments:

(unlabeled) (of type internet_address)

`host.of_name`

Find a host by name

Type:

(string) -> 
{
  addresses : [internet_address.{is_ipv6 : bool, to_string : () -> string}],
  aliases : [string],
  domain : socket_domain,
  name : string}?

Arguments:

(unlabeled) (of type string): hostname

`http.delete`

Perform a full http DELETE request.

Type:

(?headers : [string * string], ?http_version : string?, ?redirect : bool,
 ?timeout : float?, string) -> unit

Arguments:

headers (of type [string * string], which defaults to []): Additional headers.
http_version (of type string?, which defaults to null): Http request version.
redirect (of type bool, which defaults to true): Perform redirections if needed.
timeout (of type float?, which defaults to 10.): Timeout for network operations in seconds.
(unlabeled) (of type string): Requested URL, e.g. "http://www.liquidsoap.info/".

Methods:

headers (of type [string * string]): HTTP headers.
http_version (of type string): Version of the HTTP protocol.
status_code (of type int): Status code.
status_message (of type string): Status message.

`http.delete.stream`

Perform a full http DELETE request.

Type:

(?headers : [string * string], ?http_version : string?, ?redirect : bool,
 ?timeout : float?, string, on_body_data : ((string?) -> unit)) -> unit

Arguments:

headers (of type [string * string], which defaults to []): Additional headers.
http_version (of type string?, which defaults to null): Http request version.
redirect (of type bool, which defaults to true): Perform redirections if needed.
timeout (of type float?, which defaults to 10.): Timeout for network operations in seconds.
(unlabeled) (of type string): Requested URL, e.g. "http://www.liquidsoap.info/".
on_body_data (of type (string?) -> unit): function called when receiving response body data. null or "" means that all the data has been passed.

Methods:

headers (of type [string * string]): HTTP headers.
http_version (of type string): Version of the HTTP protocol.
status_code (of type int): Status code.
status_message (of type string): Status message.

`http.get`

Perform a full http GET request.

Type:

(?headers : [string * string], ?http_version : string?, ?redirect : bool,
 ?timeout : float?, string) -> string

Arguments:

headers (of type [string * string], which defaults to []): Additional headers.
http_version (of type string?, which defaults to null): Http request version.
redirect (of type bool, which defaults to true): Perform redirections if needed.
timeout (of type float?, which defaults to 10.): Timeout for network operations in seconds.
(unlabeled) (of type string): Requested URL, e.g. "http://www.liquidsoap.info/".

Methods:

headers (of type [string * string]): HTTP headers.
http_version (of type string): Version of the HTTP protocol.
status_code (of type int): Status code.
status_message (of type string): Status message.

`http.get.stream`

Perform a full http GET request.

Type:

(?headers : [string * string], ?http_version : string?, ?redirect : bool,
 ?timeout : float?, string, on_body_data : ((string?) -> unit)) -> unit

Arguments:

headers (of type [string * string], which defaults to []): Additional headers.
http_version (of type string?, which defaults to null): Http request version.
redirect (of type bool, which defaults to true): Perform redirections if needed.
timeout (of type float?, which defaults to 10.): Timeout for network operations in seconds.
(unlabeled) (of type string): Requested URL, e.g. "http://www.liquidsoap.info/".
on_body_data (of type (string?) -> unit): function called when receiving response body data. null or "" means that all the data has been passed.

Methods:

headers (of type [string * string]): HTTP headers.
http_version (of type string): Version of the HTTP protocol.
status_code (of type int): Status code.
status_message (of type string): Status message.

`http.head`

Perform a full http HEAD request.

Type:

(?headers : [string * string], ?http_version : string?, ?redirect : bool,
 ?timeout : float?, string) -> unit

Arguments:

headers (of type [string * string], which defaults to []): Additional headers.
http_version (of type string?, which defaults to null): Http request version.
redirect (of type bool, which defaults to true): Perform redirections if needed.
timeout (of type float?, which defaults to 10.): Timeout for network operations in seconds.
(unlabeled) (of type string): Requested URL, e.g. "http://www.liquidsoap.info/".

Methods:

headers (of type [string * string]): HTTP headers.
http_version (of type string): Version of the HTTP protocol.
status_code (of type int): Status code.
status_message (of type string): Status message.

`http.head.stream`

Perform a full http HEAD request.

Type:

(?headers : [string * string], ?http_version : string?, ?redirect : bool,
 ?timeout : float?, string, on_body_data : ((string?) -> unit)) -> unit

Arguments:

headers (of type [string * string], which defaults to []): Additional headers.
http_version (of type string?, which defaults to null): Http request version.
redirect (of type bool, which defaults to true): Perform redirections if needed.
timeout (of type float?, which defaults to 10.): Timeout for network operations in seconds.
(unlabeled) (of type string): Requested URL, e.g. "http://www.liquidsoap.info/".
on_body_data (of type (string?) -> unit): function called when receiving response body data. null or "" means that all the data has been passed.

Methods:

headers (of type [string * string]): HTTP headers.
http_version (of type string): Version of the HTTP protocol.
status_code (of type int): Status code.
status_message (of type string): Status message.

`http.headers.content_disposition`

Extract the content-disposition header

Type:

([string * string]) -> 
{args : [string * string?], filename? : string, name? : string, type : string
}?

Arguments:

(unlabeled) (of type [string * string])

`http.headers.content_type`

Extract the content-type header

Type:

([string * string?]) -> {args : [string * string], mime : string}?

Arguments:

(unlabeled) (of type [string * string?])

`http.headers.extname`

Try to get a filename from a request’s headers.

Type:

([string * string]) -> string?

Arguments:

(unlabeled) (of type [string * string])

`http.multipart_form_data`

Prepare a list of data to be sent as multipart form data.

Type:

(?boundary : string?,
 [
  {
    attributes : [string * string],
    contents : {string},
    headers : ['a * 'b],
    name : string
  }]) -> unit

Arguments:

boundary (of type string?, which defaults to null): Specify boundary to use for multipart/form-data.
(unlabeled) (of type [ { attributes : [string * string], contents : {string}, headers : ['a * 'b], name : string }]): data to insert

Methods:

boundary (of type string):
contents (of type {string}):

`http.post`

Perform a full http POST request.

Type:

(?data : {string}, ?headers : [string * string], ?http_version : string?,
 ?redirect : bool, ?timeout : float?, string) -> string

Arguments:

data (of type {string}, which defaults to ""): POST data. Use a string getter to stream data and return "" when all data has been passed.
headers (of type [string * string], which defaults to []): Additional headers.
http_version (of type string?, which defaults to null): Http request version.
redirect (of type bool, which defaults to true): Perform redirections if needed.
timeout (of type float?, which defaults to 10.): Timeout for network operations in seconds.
(unlabeled) (of type string): Requested URL, e.g. "http://www.liquidsoap.info/".

Methods:

headers (of type [string * string]): HTTP headers.
http_version (of type string): Version of the HTTP protocol.
status_code (of type int): Status code.
status_message (of type string): Status message.

`http.post.file`

Send a file via POST request encoded in multipart/form-data. The contents can either be directly specified (with the contents argument) or taken from a file (with the file argument).

Type:

(?name : string, ?content_type : string?, ?headers : [string * string],
 ?boundary : string?, ?filename : string?, ?file : string?,
 ?contents : {string}?, ?timeout : float?, ?redirect : bool, string) ->
string

Arguments:

name (of type string, which defaults to "file"): Name of the field field
content_type (of type string?, which defaults to null): Content-type (mime) for the file.
headers (of type [string * string], which defaults to []): Additional headers.
boundary (of type string?, which defaults to null): Specify boundary to use for multipart/form-data.
filename (of type string?, which defaults to null): File name sent in the request.
file (of type string?, which defaults to null): File whose contents is to be sent in the request.
contents (of type {string}?, which defaults to null): Contents of the file sent in the request.
timeout (of type float?, which defaults to null): Timeout in seconds.
redirect (of type bool, which defaults to true): Follow reidrections.
(unlabeled) (of type string): URL to post to.

Methods:

headers (of type [string * string]): HTTP headers.
http_version (of type string): Version of the HTTP protocol.
status_code (of type int): Status code.
status_message (of type string): Status message.

`http.post.stream`

Perform a full http POST request.

Type:

(?data : {string}, ?headers : [string * string], ?http_version : string?,
 ?redirect : bool, ?timeout : float?, string,
 on_body_data : ((string?) -> unit)) -> unit

Arguments:

data (of type {string}, which defaults to ""): POST data. Use a string getter to stream data and return "" when all data has been passed.
headers (of type [string * string], which defaults to []): Additional headers.
http_version (of type string?, which defaults to null): Http request version.
redirect (of type bool, which defaults to true): Perform redirections if needed.
timeout (of type float?, which defaults to 10.): Timeout for network operations in seconds.
(unlabeled) (of type string): Requested URL, e.g. "http://www.liquidsoap.info/".
on_body_data (of type (string?) -> unit): function called when receiving response body data. null or "" means that all the data has been passed.

Methods:

headers (of type [string * string]): HTTP headers.
http_version (of type string): Version of the HTTP protocol.
status_code (of type int): Status code.
status_message (of type string): Status message.

`http.put`

Perform a full http PUT request.

Type:

(?data : {string}, ?headers : [string * string], ?http_version : string?,
 ?redirect : bool, ?timeout : float?, string) -> string

Arguments:

data (of type {string}, which defaults to ""): POST data. Use a string getter to stream data and return "" when all data has been passed.
headers (of type [string * string], which defaults to []): Additional headers.
http_version (of type string?, which defaults to null): Http request version.
redirect (of type bool, which defaults to true): Perform redirections if needed.
timeout (of type float?, which defaults to 10.): Timeout for network operations in seconds.
(unlabeled) (of type string): Requested URL, e.g. "http://www.liquidsoap.info/".

Methods:

headers (of type [string * string]): HTTP headers.
http_version (of type string): Version of the HTTP protocol.
status_code (of type int): Status code.
status_message (of type string): Status message.

`http.put.file`

Send a file via PUT request encoded in multipart/form-data. The contents can either be directly specified (with the contents argument) or taken from a file (with the file argument).

Type:

(?name : string, ?content_type : string?, ?headers : [string * string],
 ?boundary : string?, ?filename : string?, ?file : string?,
 ?contents : {string}?, ?timeout : float?, ?redirect : bool, string) ->
string

Arguments:

name (of type string, which defaults to "file"): Name of the field field
content_type (of type string?, which defaults to null): Content-type (mime) for the file.
headers (of type [string * string], which defaults to []): Additional headers.
boundary (of type string?, which defaults to null): Specify boundary to use for multipart/form-data.
filename (of type string?, which defaults to null): File name sent in the request.
file (of type string?, which defaults to null): File whose contents is to be sent in the request.
contents (of type {string}?, which defaults to null): Contents of the file sent in the request.
timeout (of type float?, which defaults to null): Timeout in seconds.
redirect (of type bool, which defaults to true): Follow reidrections.
(unlabeled) (of type string): URL to put to.

Methods:

headers (of type [string * string]): HTTP headers.
http_version (of type string): Version of the HTTP protocol.
status_code (of type int): Status code.
status_message (of type string): Status message.

`http.put.stream`

Perform a full http PUT request.

Type:

(?data : {string}, ?headers : [string * string], ?http_version : string?,
 ?redirect : bool, ?timeout : float?, string,
 on_body_data : ((string?) -> unit)) -> unit

Arguments:

data (of type {string}, which defaults to ""): POST data. Use a string getter to stream data and return "" when all data has been passed.
headers (of type [string * string], which defaults to []): Additional headers.
http_version (of type string?, which defaults to null): Http request version.
redirect (of type bool, which defaults to true): Perform redirections if needed.
timeout (of type float?, which defaults to 10.): Timeout for network operations in seconds.
(unlabeled) (of type string): Requested URL, e.g. "http://www.liquidsoap.info/".
on_body_data (of type (string?) -> unit): function called when receiving response body data. null or "" means that all the data has been passed.

Methods:

headers (of type [string * string]): HTTP headers.
http_version (of type string): Version of the HTTP protocol.
status_code (of type int): Status code.
status_message (of type string): Status message.

`http.response`

Initiate a response handler with pre-filled values.

Type:

(?http_version : string, ?status_code : int?, ?status_message : string?,
 ?headers : [string * string], ?content_type : string?, ?data : {string}) ->
() -> string

Arguments:

http_version (of type string, which defaults to "1.1")
status_code (of type int?, which defaults to null)
status_message (of type string?, which defaults to null)
headers (of type [string * string], which defaults to [])
content_type (of type string?, which defaults to null)
data (of type {string}, which defaults to "")

Methods:

content_type (of type ((string?) -> unit).{current : () -> string?}): Set "Content-Type" header
data (of type (({string}) -> unit).{current : () -> {string}}): Set response data.
header (of type (string, string) -> unit): Set a single header on the response
headers (of type (([string * string]) -> unit).{current : () -> [string * string]}): Replace response headers.
html (of type ({string}) -> unit): Set content-type to html and data to argument value
http_version (of type ((string) -> unit).{current : () -> string}): Set http protocol version
json (of type ('A) -> unit): Set content-type to json and data to json.stringify of the argument
multipart_form (of type (?boundary : string?, [ { attributes : [string * string], contents : {string}, headers : ['A * 'B], name : string }]) -> unit):
redirect (of type (?status_code : int, string) -> unit): Set status_code and Location: header for a HTTP redirect response
send_status (of type ('A.{write : (string) -> unit}) -> unit):
status_code (of type ((int) -> unit).{current : () -> int}): Set response status code
status_message (of type ((string?) -> unit).{current : () -> string?}): Set response status message
status_sent (of type () -> bool):

`http.transport.ssl`

Https transport using libssl

Type:

(?read_timeout : float?, ?write_timeout : float?, ?password : string?,
 ?min_protocol : string?, ?max_protocol : string?, ?certificate : string?,
 ?key : string?) -> http_transport

Arguments:

read_timeout (of type float?, which defaults to null): Read timeout
write_timeout (of type float?, which defaults to null): Write timeout
password (of type string?, which defaults to null): SSL certificate password
min_protocol (of type string?, which defaults to null): Minimal accepted SSL protocol. One of, from least recent to most recent: "ssl.3", "tls.1", "tls.1.1", "tls.1.2" or "tls.1.3". The most recent available protocol between client and server is negotiated when initiating communication between minimal and maximal protocol version. All protocols up to "tls.1.2" and above are now deprecated so you might want to set this value to one of those two. Default to lowest support protocol if not set.
max_protocol (of type string?, which defaults to null): Maximal accepted SSL protocol. One of, from least recent to most recent: "ssl.3", "tls.1", "tls.1.1", "tls.1.2" or "tls.1.3". The most recent available protocol between client and server is negotiated when initiating communication between minimal and maximal protocol version. Defaults to highest protocol supported if not set.
certificate (of type string?, which defaults to null): Path to certificate file. Required in server mode, e.g. input.harbor, etc. If passed in client mode, certificate is added to the list of valid certificates.
key (of type string?, which defaults to null): Path to certificate private key. Required in server mode, e.g. input.harbor, etc.

Methods:

default_port (of type int): Transport default port
name (of type string): Transport name
protocol (of type string): Transport protocol

`http.transport.tls`

Https transport using libtls

Type:

(?read_timeout : float?, ?write_timeout : float?, ?certificate : string?,
 ?key : string?) -> http_transport

Arguments:

read_timeout (of type float?, which defaults to null): Read timeout
write_timeout (of type float?, which defaults to null): Write timeout
certificate (of type string?, which defaults to null): Path to certificate file. Required in server mode, e.g. input.harbor, etc. If passed in client mode, certificate is added to the list of valid certificates.
key (of type string?, which defaults to null): Path to certificate private key. Required in server mode, e.g. input.harbor, etc. Unused in client mode.

Methods:

default_port (of type int): Transport default port
name (of type string): Transport name
protocol (of type string): Transport protocol

`http.transport.unix`

Http unencrypted transport

Type:

http_transport.{default_port : int, name : string, protocol : string}

`http.user_agent`

Default user-agent

Type:

string

`socket.address.internet_address`

Create a socket address for a internet address.

Type:

(internet_address.{is_ipv6 : bool, to_string : () -> string}, int) ->
socket_address

Arguments:

(unlabeled) (of type internet_address.{is_ipv6 : bool, to_string : () -> string}): Internet address.
(unlabeled) (of type int): port

Methods:

domain (of type socket_domain): Socket domain
internet_address (of type internet_address.{is_ipv6 : bool, to_string : () -> string}): Internet address
port (of type int): Port

`socket.address.unix`

Create a socket address for a unix file socket.

Type:

(string) -> socket_address

Arguments:

(unlabeled) (of type string): Unix socket path

Methods:

domain (of type socket_domain): Socket domain
path (of type string): Unix socket path

`socket.domain.inet`

Inet socket domain

Type:

socket_domain

`socket.domain.inet6`

Inet6 socket domain

Type:

socket_domain

`socket.domain.unix`

Unix socket domain

Type:

socket_domain

`socket.internet_address`

Return an internet address from its string representation.

Type:

(string) -> internet_address

Arguments:

(unlabeled) (of type string): Socket internet address.

Methods:

is_ipv6 (of type bool): Is the internet address a ipv6 address?
to_string (of type () -> string): String representation of the internet address

`socket.internet_address.any`

A special IPv4 address, for use only with socket.bind, representing all the Internet addresses that the host machine possesses.

Type:

internet_address.{is_ipv6 : bool, to_string : () -> string}

`socket.internet_address.ipv6.any`

A special IPv6 address, for use only with socket.bind, representing all the Internet addresses that the host machine possesses.

Type:

internet_address.{is_ipv6 : bool, to_string : () -> string}

`socket.internet_address.ipv6.loopback`

A special IPv6 address representing the host machine (::1).

Type:

internet_address.{is_ipv6 : bool, to_string : () -> string}

`socket.internet_address.loopback`

A special IPv4 address representing the host machine (127.0.0.1).

Type:

internet_address.{is_ipv6 : bool, to_string : () -> string}

`socket.pair`

Create a pair of sockets connected together.

Type:

(?domain : socket_domain, ?type : socket_type, ?protocol : int) -> socket

Arguments:

domain (of type socket_domain, which defaults to socket.domain.inet): Socket domain.
type (of type socket_type, which defaults to socket.type.stream): Socket type
protocol (of type int, which defaults to 0): Protocol type. 0 selects the default protocol for that kind of sockets.

Methods:

close (of type () -> unit): Close the socket.
non_blocking (of type (bool) -> unit): Set the non-blocking flag on the socket
read (of type ((?timeout : float?) -> string) .{wait : (?timeout : float?, (() -> unit)) -> unit}): Read data from a socket. Reading is done when the function returns an empty string "".
type (of type string): Socket type
write (of type ((?timeout : float?, string) -> unit) .{wait : (?timeout : float?, (() -> unit)) -> unit}): Write data to a socket

`socket.type.dgram`

Dgram socket type

Type:

socket_type

`socket.type.raw`

Raw socket type

Type:

socket_type

`socket.type.stream`

Stream socket type

Type:

socket_type

`socket.unix`

Create a unix socket.

Type:

(?domain : socket_domain, ?type : socket_type, ?protocol : int) -> socket

Arguments:

domain (of type socket_domain, which defaults to socket.domain.inet): Socket domain.
type (of type socket_type, which defaults to socket.type.stream): Socket type
protocol (of type int, which defaults to 0): Protocol type. 0 selects the default protocol for that kind of sockets.

Methods:

accept (of type () -> socket .{ close : () -> unit, non_blocking : (bool) -> unit, read : ((?timeout : float?) -> string) .{wait : (?timeout : float?, (() -> unit)) -> unit }, type : string, write : ((?timeout : float?, string) -> unit) .{wait : (?timeout : float?, (() -> unit)) -> unit } } * socket_address): Accept connections on the given socket. The returned socket is a socket connected to the client; the returned address is the address of the connecting client.
bind (of type (socket_address) -> unit): Bind a socket to an address.
close (of type () -> unit): Close the socket.
connect (of type (socket_address) -> unit): Connect a socket to an address.
listen (of type (int) -> unit): Set up a socket for receiving connection requests. The integer argument is the maximal number of pending requests.
non_blocking (of type (bool) -> unit): Set the non-blocking flag on the socket
read (of type ((?timeout : float?) -> string) .{wait : (?timeout : float?, (() -> unit)) -> unit}): Read data from a socket. Reading is done when the function returns an empty string "".
type (of type string): Socket type
write (of type ((?timeout : float?, string) -> unit) .{wait : (?timeout : float?, (() -> unit)) -> unit}): Write data to a socket

Liquidsoap

`clock`

Assign a new clock to the given source (and to other time-dependent sources) and return the source. It is a conveniency wrapper around clock.assign_new(), allowing more concise scripts in some cases.

Type:

(?sync : string, ?id : string?, source('a)) -> source('a)

Arguments:

sync (of type string, which defaults to "auto"): Synchronization mode. One of: "auto", "cpu", or "none". Defaults to "auto", which synchronizes with the CPU clock if none of the active sources are attached to their own clock (e.g. ALSA input, etc). "cpu" always synchronizes with the CPU clock. "none" removes all synchronization control.
id (of type string?, which defaults to null)
(unlabeled) (of type source('a))

`clock.assign_new`

Create a new clock and assign it to a list of sources.

Type:

(?id : string?,
 ?on_error : ((error
               .{
                 kind : string,
                 message : string,
                 trace : [
                          {
                            position_end : 
                            {
                              character_offset : int,
                              filename : string,
                              line_number : int
                            },
                            position_start : 
                            {
                              character_offset : int,
                              filename : string,
                              line_number : int
                            },
                            to_string : (?prefix : string) -> string
                          }]
               }) -> unit)?,
 ?sync : string, [source('a)]) -> unit

Arguments:

id (of type string?, which defaults to null): Identifier for the new clock. The default empty string means that the identifier of the first source will be used.
on_error (of type ((error .{ kind : string, message : string, trace : [ { position_end : {character_offset : int, filename : string, line_number : int }, position_start : {character_offset : int, filename : string, line_number : int }, to_string : (?prefix : string) -> string }] }) -> unit)?, which defaults to null): Error callback executed when a streaming error occurs. When passed, all streaming errors are silenced. Intended mostly for debugging purposes.
sync (of type string, which defaults to "auto"): Synchronization mode. One of: "auto", "cpu", or "none". Defaults to "auto", which synchronizes with the CPU clock if none of the active sources are attached to their own clock (e.g. ALSA input, etc). "cpu" always synchronizes with the CPU clock. "none" removes all synchronization control.
(unlabeled) (of type [source('a)]): List of sources to which the new clock will be assigned.

`clock.log`

Create a log of clock times for all the clocks initially present. The log is in a simple format which you can directly use with gnuplot.

Type:

(?delay : float, ?every : float, string) -> unit

Arguments:

delay (of type float, which defaults to 0.): Delay before setting up the clock logger. This should be used to ensure that the logger starts only after the clocks are created.
every (of type float, which defaults to 1.): Polling interval.
(unlabeled) (of type string): Path of the log file.

`clock.status`

Get the current time (in clock ticks) for all allocated clocks.

Type:

() -> [string * int]

`clock.status.seconds`

Get the current time in seconds for all allocated clocks.

Type:

() -> [string * float]

`clock.unify`

Enforce that a list of sources all belong to the same clock.

Type:

([source('a)]) -> unit

Arguments:

(unlabeled) (of type [source('a)])

`decoder.add`

Register an external decoder. The encoder should output in WAV format to his standard output (stdout) and read data from its standard input (stdin).

Type:

(name : string, description : string, ?mimes : [string],
 ?file_extensions : [string], ?priority : int, test : ((string) -> int),
 string) -> unit

Arguments:

name (of type string): Format/decoder’s name.
description (of type string): Description of the decoder.
mimes (of type [string], which defaults to []): List of mime types supported by this decoder. Empty means any mime type should be accepted.
file_extensions (of type [string], which defaults to []): List of file extensions. Empty means any file extension should be accepted.
priority (of type int, which defaults to 1): Decoder priority
test (of type (string) -> int): Function used to determine if a file should be decoded by the decoder. Returned values are: 0: no decodable audio, -1: decodable audio but number of audio channels unknown, x: fixed number of decodable audio channels.
(unlabeled) (of type string): Process to start.

`decoder.metadata.add`

Type:

(string, ((metadata : [string * string], string) -> [string * string])) ->
unit

Arguments:

(unlabeled) (of type string): Format/resolver’s name.
(unlabeled) (of type (metadata : [string * string], string) -> [string * string]): Process to start. The function takes the format and filename as argument and returns a list of (name,value) fields.

`decoder.oblivious.add`

Register an external file decoder. The encoder should output in WAV format to his standard output (stdout) and read data from the file it receives. The estimated remaining duration for this decoder will be unknown until the buffer last seconds of the file. If possible, it is recommended to decode from stdin and use decoder.add.

Type:

(name : string, description : string, test : ((string) -> int),
 ?priority : int, ?mimes : [string], ?file_extensions : [string],
 ?buffer : float, ((string) -> string)) -> unit

Arguments:

name (of type string): Format/decoder’s name.
description (of type string): Description of the decoder.
test (of type (string) -> int): Function used to determine if a file should be decoded by the decoder. Returned values are: 0: no decodable audio, -1: decodable audio but number of audio channels unknown, x: fixed number of decodable audio channels.
priority (of type int, which defaults to 1): Decoder priority
mimes (of type [string], which defaults to []): List of mime types supported by this decoder. Empty means any mime type should be accepted.
file_extensions (of type [string], which defaults to []): List of file extensions. Empty means any file extension should be accepted.
buffer (of type float, which defaults to 5.)
(unlabeled) (of type (string) -> string): Process to start. The function takes the filename as argument and returns the process to start.

`enable_external_faad_decoder`

Enable or disable external FAAD (AAC/AAC+/M4A) decoders. Does not work on Win32. Please note that built-in support for faad is available in liquidsoap if compiled and should be preferred over the external decoder.

Type:

() -> unit

`enable_external_ffmpeg_decoder`

Enable ffmpeg decoder.

Type:

() -> unit

`enable_external_flac_decoder`

Enable external FLAC decoders. Please note that built-in support for FLAC is available in liquidsoap if compiled and should be preferred over the external decoder.

Type:

() -> unit

`enable_external_mpc_decoder`

Enable external Musepack decoder.

Type:

() -> unit

`enable_replaygain_metadata`

Enable ReplayGain metadata resolver. This resolver will process any file decoded by Liquidsoap and add a replaygain_track_gain metadata when this value could be computed. For a finer-grained replay gain processing, use the replaygain: protocol.

Type:

() -> unit

`encoder.content_type`

Return the content-type (mime) of an encoder, if known.

Type:

(format('a)) -> string

Arguments:

(unlabeled) (of type format('a))

`encoder.extension`

Return the file extension of an encoder, if known.

Type:

(format('a)) -> string

Arguments:

(unlabeled) (of type format('a))

`liquidsoap.chroot.make`

Export all the files required to install liquidsoap in a root folder. Useful for packaging and docker images.

Type:

(string) -> unit

Arguments:

(unlabeled) (of type string)

`liquidsoap.executable`

Path to the Liquidsoap executable.

Type:

string

`liquidsoap.version.at_least`

Ensure that Liquidsoap version is greater or equal to given one.

Type:

(string) -> bool

Arguments:

(unlabeled) (of type string): Minimal version.

`log`

Log a message.

Type:

(?label : string, ?level : int, string) -> unit

Arguments:

label (of type string, which defaults to "lang")
level (of type int, which defaults to 3)
(unlabeled) (of type string)

`log.critical`

Log a critical message

Type:

(?label : string, string) -> unit

Arguments:

label (of type string, which defaults to "lang")
(unlabeled) (of type string)

`log.debug`

Log a debug message

Type:

(?label : string, string) -> unit

Arguments:

label (of type string, which defaults to "lang")
(unlabeled) (of type string)

`log.file`

Get and set the file logging

Type:

() -> bool

`log.important`

Log an important message

Type:

(?label : string, string) -> unit

Arguments:

label (of type string, which defaults to "lang")
(unlabeled) (of type string)

`log.info`

Log a normal message

Type:

(?label : string, string) -> unit

Arguments:

label (of type string, which defaults to "lang")
(unlabeled) (of type string)

`log.level`

Get and set the log level.

Type:

() -> int

`log.severe`

Log a severe message

Type:

(?label : string, string) -> unit

Arguments:

label (of type string, which defaults to "lang")
(unlabeled) (of type string)

`log.stdout`

Get and set logging to stdout

Type:

() -> bool

`playlist.parse`

Try to parse a local playlist. Return a list of (metadata,URI) items, where metadata is a list of (key,value) bindings.

Type:

(?path : string, ?mime : string?, string) -> [[string * string] * string]

Arguments:

path (of type string, which defaults to ""): Default path for files.
mime (of type string?, which defaults to null): Mime type for the playlist
(unlabeled) (of type string)

`playlist.parse.register`

Type:

(format : string, strict : bool,
 ((?pwd : string, string) -> [[string * string] * string])) -> unit

Arguments:

format (of type string): Playlist format. If possible, a mime-type.
strict (of type bool): True if playlist format can be detected unambiguously.
(unlabeled) (of type (?pwd : string, string) -> [[string * string] * string]): Playlist parser

`process.uri`

Create a process: uri, replacing : with $(colon).

Type:

(?timeout : 'a?, extname : 'b, ?uri : string, string) -> string

Arguments:

timeout (of type 'a?, which defaults to null)
extname (of type 'b): Output file extension (with no leading ‘.’)
uri (of type string, which defaults to ""): Input uri
(unlabeled) (of type string): Command line to execute

`profiler.disable`

Record profiling statistics.

Type:

() -> unit

`profiler.enable`

Record profiling statistics.

Type:

() -> unit

`profiler.print`

Print profiling information.

Type:

() -> unit

`profiler.run`

Time a function with the profiler.

Type:

(string, (() -> 'a)) -> 'a

Arguments:

(unlabeled) (of type string): Name of the profiled function.
(unlabeled) (of type () -> 'a): Function to profile.

`profiler.stats.string`

Profiling statistics.

Type:

() -> string

`prometheus.latency`

Monitor a source’s internal latencies on Prometheus

Type:

(?window : float, ?prefix : string, labels : [string]) ->
(label_values : [string], source('a)) -> unit

Arguments:

window (of type float, which defaults to 5.): Window over which mean and peak metrics are reported.
prefix (of type string, which defaults to "liquidsoap_"): Prefix for the metric’s name
labels (of type [string]): labels for the metric

`protocol.add`

Type:

(?temporary : bool, ?static : bool, ?syntax : string, ?doc : string, string,
 ((rlog : ((string) -> unit), maxtime : float, string) -> [string])) -> unit

Arguments:

temporary (of type bool, which defaults to false): if true, file is removed when it is finished.
static (of type bool, which defaults to false): if true, then requests can be resolved once and for all. Typically, static protocols can be used to create infallible sources.
syntax (of type string, which defaults to "Undocumented"): URI syntax.
doc (of type string, which defaults to "Undocumented"): Protocol documentation.
(unlabeled) (of type string): Protocol name. Resolver will be called on uris of the form: <protocol name>:....
(unlabeled) (of type (rlog : ((string) -> unit), maxtime : float, string) -> [string]): Protocol resolver. Receives a function to log protocol resolution, the <arg> in <protocol name>:<arg> and the max delay that resolution should take.

`request.create`

Create a request from an URI.

Type:

(?indicators : [string], ?persistent : bool, ?resolve_metadata : bool,
 ?temporary : bool, string) -> request

Arguments:

indicators (of type [string], which defaults to [])
persistent (of type bool, which defaults to false): Indicate that the request is persistent, i.e. that it may be used again once it has been played.
resolve_metadata (of type bool, which defaults to true): Set to false to prevent metadata resolution on this request.
temporary (of type bool, which defaults to false): Indicate that the request is a temporary file: it will be destroyed after being played.
(unlabeled) (of type string)

`request.destroy`

Destroying a request causes any temporary associated file to be deleted, and releases its RID. Persistent requests resist to destroying, unless forced.

Type:

(?force : bool, request) -> unit

Arguments:

force (of type bool, which defaults to false): Destroy the request even if it is persistent.
(unlabeled) (of type request)

`request.duration`

Compute the duration in seconds of audio data contained in a request. The computation may be expensive. Returns null if computation failed, typically if the file was not recognized as valid audio.

Type:

(?metadata : [string * string], string) -> float?

Arguments:

metadata (of type [string * string], which defaults to []): Optional metadata used to decode the file, e.g. ffmpeg_options.
(unlabeled) (of type string)

`request.filename`

Return a valid local filename if the request is ready, and the empty string otherwise.

Type:

(request) -> string

Arguments:

(unlabeled) (of type request)

`request.id`

Identifier of a request.

Type:

(request) -> int

Arguments:

(unlabeled) (of type request)

`request.log`

Get log data associated to a request.

Type:

(request) -> string

Arguments:

(unlabeled) (of type request)

`request.metadata`

Get the metadata associated to a request.

Type:

(request) -> [string * string]

Arguments:

(unlabeled) (of type request)

`request.read_metadata`

Force reading the metadata of a request.

Type:

(request) -> unit

Arguments:

(unlabeled) (of type request)

`request.resolve`

Resolve a request, i.e. attempt to get a valid local file. The operation can take some time. Return true if the resolving was successful, false otherwise (timeout or invalid URI). The request should not be decoded afterward: this is mostly useful to download files such as playlists, etc.

Type:

(?content_type : source('a)?, ?timeout : float, request) -> bool

Arguments:

content_type (of type source('a)?, which defaults to null): If specified, the request will be decoded with the same content type as the given source.
timeout (of type float, which defaults to 30.): Limit in seconds to the duration of the resolving.
(unlabeled) (of type request)

`request.resolved`

Check if a request is resolved, i.e. is associated to a valid local file.

Type:

(request) -> bool

Arguments:

(unlabeled) (of type request)

`request.status`

Current status of a request. Can be idle, resolving, ready, playing or destroyed.

Type:

(request) -> string

Arguments:

(unlabeled) (of type request)

`request.uri`

Initial URI of a request.

Type:

(request) -> string

Arguments:

(unlabeled) (of type request)

`runtime.cpu.usage_getter`

Create a function returning CPU usage (in float percent so 0.2 means 20%) since the last time it was called.

Type:

() -> () -> {system : float, total : float, user : float}

`runtime.gc.compact`

Perform a full major collection and compact the heap. Note that heap compaction is a lengthy operation.

Type:

() -> unit

`runtime.gc.full_major`

Trigger full major garbage collection.

Type:

() -> unit

`runtime.gc.major`

Trigger a minor collection and finish the current major collection cycle..

Type:

() -> unit

`runtime.gc.major_slice`

Do a minor collection and a slice of major collection. The optional argument n is the size of the slice: the GC will do enough work to free (on average) n words of memory. If 0 (its default), the GC will try to do enough work to ensure that the next automatic slice has no work to do.

Type:

(?int) -> unit

Arguments:

(unlabeled) (of type int, which defaults to 0): Size of the slice

`runtime.gc.minor`

Trigger full minor garbage collection.

Type:

() -> unit

`runtime.memory`

Returns information about the system and process’ memory usage. Requires mem_usage for a full report.

Type:

() -> unit

Methods:

pretty (of type { process_managed_memory : string, process_physical_memory : string, process_virtual_memory : string, total_physical_memory : string, total_used_physical_memory : string, total_used_virtual_memory : string, total_virtual_memory : string }):
process_managed_memory (of type int):
process_physical_memory (of type int):
process_virtual_memory (of type int):
total_physical_memory (of type int):
total_used_physical_memory (of type int):
total_used_virtual_memory (of type int):
total_virtual_memory (of type int):

`seconds_of_main`

Convert a number of main ticks in seconds.

Type:

(int) -> float

Arguments:

(unlabeled) (of type int)

`server.execute`

Execute a liquidsoap server command.

Type:

(string, ?string) -> [string]

Arguments:

(unlabeled) (of type string): Command to execute.
(unlabeled) (of type string, which defaults to ""): Argument for the command.

List

`_::_`

Add an element at the top of a list.

Type:

('a, ['a]) -> ['a]

Arguments:

(unlabeled) (of type 'a)
(unlabeled) (of type ['a])

`_[_]`

l[k] returns the first v such that (k,v) is in the list l (or “” if no such v exists).

Type:

(['a * string], 'a) -> string where 'a is an orderable type

Arguments:

(unlabeled) (of type ['a * string] where 'a is an orderable type)
(unlabeled) (of type anything that is an orderable type)

`list.add`

Add an element at the top of a list.

Type:

('a, ['a]) -> ['a]

Arguments:

(unlabeled) (of type 'a)
(unlabeled) (of type ['a])

`list.append`

Concatenate two lists.

Type:

(['a], ['a]) -> ['a]

Arguments:

(unlabeled) (of type ['a])
(unlabeled) (of type ['a])

`list.assoc`

Associate a value to a key in an association list. This functions raises error.not_found if no default value is specified.

Type:

(?default : 'a?, 'b, ['b * 'a]) -> 'a where 'b is an orderable type

Arguments:

default (of type 'a?, which defaults to null): Value returned if the key is not found.
(unlabeled) (of type anything that is an orderable type)
(unlabeled) (of type ['b * 'a] where 'b is an orderable type)

`list.assoc.filter`

Keep only the elements of an association list satisfying a given predicate.

Type:

((('a, 'b) -> bool), ['a * 'b]) -> ['a * 'b]

Arguments:

(unlabeled) (of type ('a, 'b) -> bool)
(unlabeled) (of type ['a * 'b])

`list.assoc.filter_map`

Map a function of every element of the associative list, removing the entry if the function returns null.

Type:

((('a, 'b) -> 'c?), ['a * 'b]) -> ['c]

Arguments:

(unlabeled) (of type ('a, 'b) -> 'c?)
(unlabeled) (of type ['a * 'b])

`list.assoc.mem`

list.assoc.mem(key,l) returns true if l contains a pair (key,value).

Type:

('a, ['a * 'b]) -> bool where 'a is an orderable type

Arguments:

(unlabeled) (of type anything that is an orderable type): Key to look for
(unlabeled) (of type ['a * 'b] where 'a is an orderable type): List of pairs (key,value)

`list.assoc.remove`

Remove the first pair from an associative list.

Type:

('a, ['a * 'b]) -> ['a * 'b] where 'a is an orderable type

Arguments:

(unlabeled) (of type anything that is an orderable type): Key of pair to be removed.
(unlabeled) (of type ['a * 'b] where 'a is an orderable type): List of pairs (key,value).

`list.assoc.remove.all`

Remove all pairs with given key from an associative list.

Type:

('a, ['a * 'b]) -> ['a * 'b] where 'a is an orderable type

Arguments:

(unlabeled) (of type anything that is an orderable type): Key of pairs to be removed.
(unlabeled) (of type ['a * 'b] where 'a is an orderable type): List of pairs (key,value).

`list.case`

Define a function by case analysis, depending on whether a list is empty or not.

Type:

(['a], 'b, (('a, ['a]) -> 'b)) -> 'b

Arguments:

(unlabeled) (of type ['a]): List to perform case analysis on.
(unlabeled) (of type 'b): Result when the list is empty.
(unlabeled) (of type ('a, ['a]) -> 'b): Result when the list is non-empty.

`list.cons`

Add an element at the top of a list.

Type:

('a, ['a]) -> ['a]

Arguments:

(unlabeled) (of type 'a)
(unlabeled) (of type ['a])

`list.dcase`

“Delayed” version of list.case where the value on empty list is only evaluated if necessary.

Type:

(['a], (() -> 'b), (('a, ['a]) -> 'b)) -> 'b

Arguments:

(unlabeled) (of type ['a])
(unlabeled) (of type () -> 'b)
(unlabeled) (of type ('a, ['a]) -> 'b)

`list.exists`

Check that a predicate is satisfied for some element in a list.

Type:

((('a) -> bool), ['a]) -> bool

Arguments:

(unlabeled) (of type ('a) -> bool): Predicate.
(unlabeled) (of type ['a]): List

`list.filter`

Filter a list according to a predicate. The order in which elements are handled is not specified (and is currently implemented from the right).

Type:

(?remove : (('a) -> unit), (('a) -> bool), ['a]) -> ['a]

Arguments:

remove (of type ('a) -> unit, which defaults to fun (_) -> ()): Function called on an element when it is removed.
(unlabeled) (of type ('a) -> bool): Predicate indicating whether an element should be kept or not.
(unlabeled) (of type ['a]): List to filter.

`list.filter_map`

Map a function on a list (like list.map) excepting that the value is removed if the function returns null.

Type:

((('a) -> 'b?), ['a]) -> ['b]

Arguments:

(unlabeled) (of type ('a) -> 'b?): Function called on every element of the list.
(unlabeled) (of type ['a]): The list.

`list.find`

First element satisfying a predicate. Raises error.not_found if not element is found and no default value was specified.

Type:

(?default : 'a?, (('a) -> bool), ['a]) -> 'a

Arguments:

default (of type 'a?, which defaults to null): Returned value when the predicate is not found.
(unlabeled) (of type ('a) -> bool): Predicate.
(unlabeled) (of type ['a]): List

`list.flatten`

Concatenate all the elements of a list of lists.

Type:

([['a]]) -> ['a]

Arguments:

(unlabeled) (of type [['a]])

`list.fold`

Fold a function on every element of a list: list.fold(f,x1,[e1,..,en]) is f(...f(f(x1,e1),e2)...,en).

Type:

((('a, 'b) -> 'a), 'a, ['b]) -> 'a

Arguments:

(unlabeled) (of type ('a, 'b) -> 'a): Function f for which f(x,e) which will be called on every element e with the current value of x, returning the new value of x.
(unlabeled) (of type 'a): Initial value x1, to be updated by successive calls of f(x,e).
(unlabeled) (of type ['b])

`list.fold.right`

Fold a function on every element of a list. Similar to list.fold but iterates from the right of the list. It is slightly more efficient than list.fold.

Type:

((('a, 'b) -> 'b), 'b, ['a]) -> 'b

Arguments:

(unlabeled) (of type ('a, 'b) -> 'b): Function f for which f(x,e) which will be called on every element e with the current value of x, returning the new value of x.
(unlabeled) (of type 'b): Initial value x1, to be updated by successive calls of f(x,e).
(unlabeled) (of type ['a])

`list.for_all`

Check that a predicate is satisfied for every element in a list.

Type:

((('a) -> bool), ['a]) -> bool

Arguments:

(unlabeled) (of type ('a) -> bool): Predicate.
(unlabeled) (of type ['a]): List

`list.hd`

Return the head (first element) of a list, or default if the list is empty.

Type:

(?default : 'a?, ['a]) -> 'a

Arguments:

default (of type 'a?, which defaults to null): Default value if key does not exist.
(unlabeled) (of type ['a])

`list.ind`

Define a function by induction on a list. This is slightly more efficient than defining a recursive function. The list is scanned from the right.

Type:

(['a], 'b, (('a, ['a], 'b) -> 'b)) -> 'b

Arguments:

(unlabeled) (of type ['a]): List to perform induction on.
(unlabeled) (of type 'b): Result when the list is empty.
(unlabeled) (of type ('a, ['a], 'b) -> 'b): Result when the list is non-empty, given the current element, the tail and the result of the recursive call on the tail.

`list.index`

First index where a predicate is satisfied.

Type:

((('a) -> bool), ['a]) -> int

Arguments:

(unlabeled) (of type ('a) -> bool): Predicate.
(unlabeled) (of type ['a]): List

`list.indexed`

Add indices to every element of a list, so that it can be accessed with the notation l[n].

Type:

(['a]) -> [int * 'a]

Arguments:

(unlabeled) (of type ['a])

`list.init`

Initialize a list.

Type:

(int, ((int) -> 'a)) -> ['a]

Arguments:

(unlabeled) (of type int): Number of elements in the list.
(unlabeled) (of type (int) -> 'a): Function such that f i is the ith element.

`list.insert`

Returns a copy of the given list with a new element inserted at a given position. Raises error.not_found if the list has less than index elements.

Type:

(int, 'a, ['a]) -> ['a]

Arguments:

(unlabeled) (of type int): Index to insert at, starting at 0.
(unlabeled) (of type 'a): Element to insert
(unlabeled) (of type ['a]): List to insert into.

`list.is_empty`

Determining whether a list is empty or not.

Type:

(['a]) -> bool

Arguments:

(unlabeled) (of type ['a])

`list.iter`

Call a function on every element of a list.

Type:

((('a) -> unit), ['a]) -> unit

Arguments:

(unlabeled) (of type ('a) -> unit)
(unlabeled) (of type ['a])

`list.iterator`

Create an iterator over the elements of a list.

Type:

(['a?]) -> () -> 'a?

Arguments:

(unlabeled) (of type ['a?])

`list.iteri`

Call a function on every element of a list, along with its index.

Type:

(((int, 'a) -> unit), ['a]) -> unit

Arguments:

(unlabeled) (of type (int, 'a) -> unit)
(unlabeled) (of type ['a])

`list.last`

Return the last element of a list.

Type:

(?default : 'a?, ['a]) -> 'a

Arguments:

default (of type 'a?, which defaults to null)
(unlabeled) (of type ['a])

`list.length`

Compute the length of a list, i.e., the number of its elements.

Type:

(['a]) -> int

Arguments:

(unlabeled) (of type ['a])

`list.make`

Create a list with given length, filled with given element.

Type:

(int, 'a) -> ['a]

Arguments:

(unlabeled) (of type int): Number of elements in the list.
(unlabeled) (of type 'a): Element to fill the list with.

`list.map`

Map a function on every element of a list.

Type:

((('a) -> 'b), ['a]) -> ['b]

Arguments:

(unlabeled) (of type ('a) -> 'b)
(unlabeled) (of type ['a])

`list.map.right`

Map a function on every element of a list, starting from the right. This function is tail-recursive.

Type:

((('a) -> 'b), ['a]) -> ['b]

Arguments:

(unlabeled) (of type ('a) -> 'b)
(unlabeled) (of type ['a])

`list.mapi`

Map a function on every element of a list, along with its index.

Type:

(((int, 'a) -> 'b), ['a]) -> ['b]

Arguments:

(unlabeled) (of type (int, 'a) -> 'b)
(unlabeled) (of type ['a])

`list.mem`

Check whether an element belongs to a list.

Type:

('a, ['a]) -> bool where 'a is an orderable type

Arguments:

(unlabeled) (of type anything that is an orderable type)
(unlabeled) (of type ['a] where 'a is an orderable type)

`list.nth`

Get the n-th element of a list (the first element is at position 0), or default if element does not exist.

Type:

(?default : 'a?, ['a], int) -> 'a

Arguments:

default (of type 'a?, which defaults to null): Default element. Raises error.not_found if null and no element can be found in the list.
(unlabeled) (of type ['a])
(unlabeled) (of type int)

`list.pick`

Pick a random element in a list.

Type:

(?default : 'a?, ['a]) -> 'a

Arguments:

default (of type 'a?, which defaults to null): Value returned if the list is empty.
(unlabeled) (of type ['a]): List in which the element should be picked.

`list.prefix`

Compute the beginning of a list.

Type:

(int, ['a]) -> ['a]

Arguments:

(unlabeled) (of type int): Number of elements in the returned list.
(unlabeled) (of type ['a]): List whose prefix should be taken.

`list.remove`

Remove the first occurrence of a value from a list.

Type:

('a, ['a]) -> ['a]

Arguments:

(unlabeled) (of type 'a)
(unlabeled) (of type ['a])

`list.rev`

Revert list order.

Type:

(['a]) -> ['a]

Arguments:

(unlabeled) (of type ['a])

`list.shuffle`

Shuffle the content of a list. The function returns a list with the same elements but in different, random, order.

Type:

(['a]) -> ['a]

Arguments:

(unlabeled) (of type ['a])

`list.sort`

Sort a list according to a comparison function.

Type:

((('a, 'a) -> int), ['a]) -> ['a]

Arguments:

(unlabeled) (of type ('a, 'a) -> int): Comparison function f such that f(x,y)<0 when x<y, f(x,y)=0 when x=y, and f(x,y)>0 when x>y.
(unlabeled) (of type ['a]): List to sort.

`list.sort.natural`

Sort a list according to the “natural” order.

Type:

(['a]) -> ['a] where 'a is an orderable type

Arguments:

(unlabeled) (of type ['a] where 'a is an orderable type): List to sort

`list.tl`

Return the list without its first element.

Type:

(['a]) -> ['a]

Arguments:

(unlabeled) (of type ['a])

Math

`*`

Multiplication of numbers.

Type:

('a, 'a) -> 'a where 'a is a number type

Arguments:

(unlabeled) (of type anything that is a number type)
(unlabeled) (of type anything that is a number type)

`+`

Addition of numbers.

Type:

('a, 'a) -> 'a where 'a is a number type

Arguments:

(unlabeled) (of type anything that is a number type)
(unlabeled) (of type anything that is a number type)

`-`

Subtraction of numbers.

Type:

('a, 'a) -> 'a where 'a is a number type

Arguments:

(unlabeled) (of type anything that is a number type)
(unlabeled) (of type anything that is a number type)

`/`

Division of numbers.

Type:

('a, 'a) -> 'a where 'a is a number type

Arguments:

(unlabeled) (of type anything that is a number type)
(unlabeled) (of type anything that is a number type)

`abs`

Absolute value.

Type:

('a) -> 'a where 'a is a number type

Arguments:

(unlabeled) (of type anything that is a number type)

`acos`

Arc cosine. The argument must fall within the range [-1.0, 1.0]. Result is in radians and is between 0.0 and pi.

Type:

(float) -> float

Arguments:

(unlabeled) (of type float)

`asin`

Arc sine. The argument must fall within the range [-1.0, 1.0]. Result is in radians and is between -pi/2 and pi/2.

Type:

(float) -> float

Arguments:

(unlabeled) (of type float)

`atan`

Arc tangent. Result is in radians and is between -pi/2 and pi/2.

Type:

(float) -> float

Arguments:

(unlabeled) (of type float)

`bool_of_float`

Convert a float to a bool.

Type:

(float) -> bool

Arguments:

(unlabeled) (of type float)

`bool_of_int`

Convert an int to a bool.

Type:

(int) -> bool

Arguments:

(unlabeled) (of type int)

`cos`

Cosine. Argument is in radians.

Type:

(float) -> float

Arguments:

(unlabeled) (of type float)

`cosh`

Hyperbolic cosine. Argument is in radians.

Type:

(float) -> float

Arguments:

(unlabeled) (of type float)

`dB_of_lin`

Convert linear scale into decibels.

Type:

(float) -> float

Arguments:

(unlabeled) (of type float)

`exp`

Exponential.

Type:

(float) -> float

Arguments:

(unlabeled) (of type float)

`float`

Convert a number to a float.

Type:

('a) -> float where 'a is a number type

Arguments:

(unlabeled) (of type anything that is a number type)

`float_of_int`

Convert an int to a float.

Type:

(int) -> float

Arguments:

(unlabeled) (of type int)

`infinity`

Float representation of infinity.

Type:

float

`int`

Convert a number to an integer.

Type:

('a) -> int where 'a is a number type

Arguments:

(unlabeled) (of type anything that is a number type)

`int_of_float`

Convert a float to a int.

Type:

(float) -> int

Arguments:

(unlabeled) (of type float)

`lin_of_dB`

Convert decibels into linear scale.

Type:

(float) -> float

Arguments:

(unlabeled) (of type float)

`ln`

Natural logarithm.

Type:

(float) -> float

Arguments:

(unlabeled) (of type float)

`log10`

Base 10 logarithm.

Type:

(float) -> float

Arguments:

(unlabeled) (of type float)

`lsl`

Logical shift left.

Type:

(int, int) -> int

Arguments:

(unlabeled) (of type int): Number to shift.
(unlabeled) (of type int): Number of bits to shift.

`lsr`

Logical shift right.

Type:

(int, int) -> int

Arguments:

(unlabeled) (of type int): Number to shift.
(unlabeled) (of type int): Number of bits to shift.

`max`

Compute the maximum of two values.

Type:

('a, 'a) -> 'a where 'a is an orderable type

Arguments:

(unlabeled) (of type anything that is an orderable type)
(unlabeled) (of type anything that is an orderable type)

`max_int`

Maximal representable integer.

Type:

int

`min`

Compute the minimum of two values.

Type:

('a, 'a) -> 'a where 'a is an orderable type

Arguments:

(unlabeled) (of type anything that is an orderable type)
(unlabeled) (of type anything that is an orderable type)

`min_int`

Minimal representable integer.

Type:

int

`mod`

Remainder of division of numbers.

Type:

('a, 'a) -> 'a where 'a is a number type

Arguments:

(unlabeled) (of type anything that is a number type)
(unlabeled) (of type anything that is a number type)

`nan`

A special floating-point value denoting the result of an undefined operation such as 0.0 /. 0.0. Stands for ‘not a number’. Any floating-point operation with nan as argument returns nan as result. As for floating-point comparisons, ==, <, <=, > and >= return false and != returns true if one or both of their arguments is nan.

Type:

float

`pow`

Exponentiation of numbers.

Type:

('a, 'a) -> 'a where 'a is a number type

Arguments:

(unlabeled) (of type anything that is a number type)
(unlabeled) (of type anything that is a number type)

`random.float`

Generate a random value between min (included) and max (excluded).

Type:

(?min : float, ?max : float) -> float

Arguments:

min (of type float, which defaults to 0.)
max (of type float, which defaults to 1.)

`random.int`

Generate a random value between min (included) and max (excluded).

Type:

(?min : int, ?max : int) -> int

Arguments:

min (of type int, which defaults to -536870911)
max (of type int, which defaults to 536870912)

`sin`

Sine. Argument is in radians.

Type:

(float) -> float

Arguments:

(unlabeled) (of type float)

`sinh`

Hyperbolic sine. Argument is in radians.

Type:

(float) -> float

Arguments:

(unlabeled) (of type float)

`sqrt`

Square root.

Type:

(float) -> float

Arguments:

(unlabeled) (of type float)

`tan`

Tangent. Argument is in radians.

Type:

(float) -> float

Arguments:

(unlabeled) (of type float)

`tanh`

Hyperbolic tangent. Argument is in radians.

Type:

(float) -> float

Arguments:

(unlabeled) (of type float)

`~-`

Returns the opposite of its argument.

Type:

('a) -> 'a where 'a is a number type

Arguments:

(unlabeled) (of type anything that is a number type)

Metadata

`file.cover`

Obtain cover-art for a file. An empty string is returned in case there is no such information.

Type:

(string) -> string
.{
  color_depth? : int,
  description? : string,
  format? : string,
  height? : int,
  mime : string,
  number_of_colors? : int?,
  picture_type? : int,
  width? : int}?

Arguments:

(unlabeled) (of type string): File from which the cover should be obtained

`metadata.artist`

Extract artist from metadata.

Type:

([string * string]) -> string

Arguments:

(unlabeled) (of type [string * string])

`metadata.comment`

Extract comment from metadata.

Type:

([string * string]) -> string

Arguments:

(unlabeled) (of type [string * string])

`metadata.cover`

Extract cover from metadata. This function implements cover extraction for the following formats: coverart (ogg), apic (flac, mp3) and pic (mp3).

Type:

(?coverart_mime : string?, [string * string]) -> string
.{
  color_depth? : int,
  description? : string,
  format? : string,
  height? : int,
  mime : string,
  number_of_colors? : int?,
  picture_type? : int,
  width? : int}?

Arguments:

coverart_mime (of type string?, which defaults to null): Mime type to use for "coverart" metadata. Support disabled if null.
(unlabeled) (of type [string * string]): Metadata from which the cover should be extracted.

`metadata.cover.remove`

Remove cover metadata. This is mostly useful in order not to flood logs with coverart when logging metadata.

Type:

([string * 'a]) -> [string * 'a]

Arguments:

(unlabeled) (of type [string * 'a])

`metadata.deduplicate`

Remove duplicate metadata in a source.

Type:

(?id : string?, source('a)) -> source('a)
where 'a is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to "metadata.deduplicate"): Source id
(unlabeled) (of type source('a) where 'a is a set of tracks to be muxed into a source): source

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`metadata.export`

Cleanup metadata for export. This is used to remove Liquidsoap’s internal metadata entries before sending them. List of exported metadata is set using settings.encoder.metadata.export.set.

Type:

([string * string]) -> [string * string]

Arguments:

(unlabeled) (of type [string * string])

`metadata.filename`

Extract filename from metadata.

Type:

([string * string]) -> string

Arguments:

(unlabeled) (of type [string * string])

`metadata.getter`

Create a getter from a metadata: this is a string, whose value can be changed with a metadata.

Type:

(string, 'a, 'c.{on_metadata : (((['a * string]) -> unit)) -> 'b}) ->
() -> string where 'a is an orderable type

Arguments:

(unlabeled) (of type string): Initial value.
(unlabeled) (of type anything that is an orderable type): Metadata on which the value should be updated.
(unlabeled) (of type 'c.{on_metadata : (((['a * string]) -> unit)) -> 'b} where 'a is an orderable type): Source containing the metadata.

`metadata.getter.float`

Create a float getter from a metadata: this is a float, whose value can be changed with a metadata.

Type:

(float, 'a, 'c.{on_metadata : (((['a * string]) -> unit)) -> 'b}) ->
() -> float where 'a is an orderable type

Arguments:

(unlabeled) (of type float): Initial value.
(unlabeled) (of type anything that is an orderable type): Metadata on which the value should be updated.
(unlabeled) (of type 'c.{on_metadata : (((['a * string]) -> unit)) -> 'b} where 'a is an orderable type): Source containing the metadata.

`metadata.json.parse`

Parse metadata from JSON object.

Type:

(string) -> [string * string] as json.object

Arguments:

(unlabeled) (of type string)

`metadata.json.stringify`

Export metadata as JSON object. Cover art, if found, is extracted using metadata.cover and exported with key "cover" and exported using string.data_uri.encode.

Type:

(?coverart_mime : string?, ?base64 : bool, ?compact : bool, ?json5 : bool,
 [string * string]) -> string

Arguments:

coverart_mime (of type string?, which defaults to null): Mime type to use for "coverart" metadata. Support disasbled if null.
base64 (of type bool, which defaults to true)
compact (of type bool, which defaults to false): Output compact text.
json5 (of type bool, which defaults to false): Use json5 extended spec.
(unlabeled) (of type [string * string])

`metadata.title`

Extract title from metadata.

Type:

([string * string]) -> string

Arguments:

(unlabeled) (of type [string * string])

`string.apic.parse`

Parse APIC ID3v2 tags (such as those obtained in the APIC tag from file.metadata.id3v2). The returned values are: mime, picture type, description, and picture data.

Type:

(string) -> string

Arguments:

(unlabeled) (of type string): APIC data.

Methods:

description (of type string): Description
mime (of type string): Mime type
picture_type (of type int): Picture type

`string.pic.parse`

Parse PIC ID3v2 tags (such as those obtained in the PIC tag from file.metadata.id3v2). The returned values are: format, picture type, description, and picture data.

Type:

(string) -> string

Arguments:

(unlabeled) (of type string): PIC data.

Methods:

description (of type string): Description
format (of type string): Picture format
picture_type (of type int): Picture type

`track.metadata.deduplicate`

Remove duplicate metadata in a track.

Type:

(?id : string?, metadata) -> metadata

Arguments:

id (of type string?, which defaults to "track.metadata.deduplicate")
(unlabeled) (of type metadata)

Programming

`assert`

Ensure that a condition is satisfied (raise error.assertion exception otherwise).

Type:

(bool) -> unit

Arguments:

(unlabeled) (of type bool): Condition which should be satisfied.

`error.on_error`

Register a callback to monitor errors raised during the execution of the program. The callback is allow to re-raise a different error if needed.

Type:

(((error
   .{
     kind : string,
     message : string,
     trace : [
              {
                position_end : 
                {character_offset : int, filename : string, line_number : int
                },
                position_start : 
                {character_offset : int, filename : string, line_number : int
                },
                to_string : (?prefix : string) -> string
              }]
   }) -> unit)) -> unit

Arguments:

(unlabeled) (of type (error .{ kind : string, message : string, trace : [ { position_end : {character_offset : int, filename : string, line_number : int }, position_start : {character_offset : int, filename : string, line_number : int }, to_string : (?prefix : string) -> string }] }) -> unit)

`error.raise`

Raise an error.

Type:

(error, ?string) -> 'a

Arguments:

(unlabeled) (of type error): Error kind.
(unlabeled) (of type string, which defaults to ""): Description of the error.

`error.register`

Type:

(string) -> error

Arguments:

(unlabeled) (of type string): Kind of the error

Methods:

kind (of type string): Error kind.
message (of type string): Error message.
trace (of type [ { position_end : {character_offset : int, filename : string, line_number : int }, position_start : {character_offset : int, filename : string, line_number : int }, to_string : (?prefix : string) -> string }]): Error stacktrace.

`failwith`

Major failure.

Type:

(string) -> 'a

Arguments:

(unlabeled) (of type string): Explanation about the failure.

`fst`

Get the first component of a pair.

Type:

(('a * 'b)) -> 'a

Arguments:

(unlabeled) (of type 'a * 'b)

`ignore`

Convert anything to unit, preventing warnings.

Type:

('a) -> unit

Arguments:

(unlabeled) (of type 'a)

`memoize`

Memoize the result of a function, making sure it is only executed once.

Type:

((() -> 'a)) -> () -> 'a where 'a is an orderable type

Arguments:

(unlabeled) (of type () -> 'a where 'a is an orderable type)

`null`

Create a nullable value.

Type:

(?'a?) -> 'a?

Arguments:

(unlabeled) (of type 'a?, which defaults to null): Value to make nullable.

`null.case`

Return a result dending on whether a value is nothing or not.

Type:

('a?, (() -> 'b), (('a) -> 'b)) -> 'b

Arguments:

(unlabeled) (of type 'a?): Value to reason by case analysis on.
(unlabeled) (of type () -> 'b): Value to return in case we have nothing.
(unlabeled) (of type ('a) -> 'b): Value to return in case we have something.

`null.default`

Return a result dending on whether a value is nothing or not.

Type:

('a?, (() -> 'a)) -> 'a

Arguments:

(unlabeled) (of type 'a?): Value to reason by case analysis on.
(unlabeled) (of type () -> 'a): Value to return in case we have nothing.

`null.defined`

Determine whether a nullable value is not null.

Type:

('a?) -> bool

Arguments:

(unlabeled) (of type 'a?)

`null.find`

Find the first element of a list for which the image of the function is not null. Raises error.not_found if not element is found and no default value was specified.

Type:

(?default : 'a??, (('b) -> 'a?), ['b]) -> 'a?

Arguments:

default (of type 'a??, which defaults to null): Returned value when no element is found.
(unlabeled) (of type ('b) -> 'a?): Function.
(unlabeled) (of type ['b]): List.

`null.get`

Get the value of a nullable. Raises error.not_found if the value is null and no default value was specified.

Type:

(?default : 'a?, 'a?) -> 'a

Arguments:

default (of type 'a?, which defaults to null): Returned value when the value is null.
(unlabeled) (of type 'a?)

`null.map`

Apply a function on a nullable value if it is not null, and return null otherwise.

Type:

((('a) -> 'b?), 'a?) -> 'b?

Arguments:

(unlabeled) (of type ('a) -> 'b?)
(unlabeled) (of type 'a?)

`null.to_list`

Convert a nullable value to a list containing zero or one element depending on whether the value is null or not.

Type:

('a?) -> ['a]

Arguments:

(unlabeled) (of type 'a?)

`position`

Return the current position in the script

Type:

() -> unit

Methods:

character_offset (of type int): character offset
filename (of type string): filename
line_number (of type int): line number

`predicate.activates`

Detect when a predicate becomes true.

Type:

(?init : bool, (() -> bool)) -> () -> bool

Arguments:

init (of type bool, which defaults to false): Detect at beginning.
(unlabeled) (of type () -> bool): Predicate.

`predicate.at_most`

Limit the number of times a predicate is true is a row.

Type:

(int, (() -> bool)) -> () -> bool

Arguments:

(unlabeled) (of type int): Number of times the predicate is allowed to be true.
(unlabeled) (of type () -> bool): Predicate.

`predicate.changes`

Detect when a predicate changes.

Type:

((() -> 'a)) -> () -> bool where 'a is an orderable type

Arguments:

(unlabeled) (of type () -> 'a where 'a is an orderable type): Predicate.

`predicate.first`

First occurrence of a predicate.

Type:

((() -> bool)) -> () -> bool

Arguments:

(unlabeled) (of type () -> bool): Predicate.

`predicate.once`

Become true once every time a predicate is true.

Type:

((() -> bool)) -> () -> bool

Arguments:

(unlabeled) (of type () -> bool): Predicate.

`predicate.signal`

Predicate which is true when a signal is sent. The returned predicate has a method signal to send the signal.

Type:

() -> () -> bool

Methods:

signal (of type () -> unit): Send a signal.

`print`

Print on standard output.

Type:

(?newline : bool, 'a) -> unit

Arguments:

newline (of type bool, which defaults to true): If true, a newline is added after displaying the value.
(unlabeled) (of type 'a)

`ref`

Create a reference, i.e. a value which can be modified.

Type:

('a) -> () -> 'a

Arguments:

(unlabeled) (of type 'a)

Methods:

set (of type ('A) -> unit): Set the value of the reference.

`ref.getter`

Create a getter from a reference (sometimes useful to remove the set method).

Type:

((() -> 'a).{set : ('a) -> unit}) -> () -> 'a

Arguments:

(unlabeled) (of type (() -> 'a).{set : ('a) -> unit})

`ref.incr`

Increment a reference to an integer.

Type:

((() -> int).{set : (int) -> 'a}) -> 'a

Arguments:

(unlabeled) (of type (() -> int).{set : (int) -> 'a})

`ref.make`

Create a reference from a pair of get / set functions.

Type:

((() -> 'a), (('a) -> unit)) -> () -> 'a

Arguments:

(unlabeled) (of type () -> 'a): Function to retrieve the value of the reference.
(unlabeled) (of type ('a) -> unit): Function to change the value of the reference.

Methods:

set (of type ('A) -> unit): Set the value of the reference.

`ref.map`

Map functions to a reference.

Type:

((('a) -> 'b), (('b) -> 'a), (() -> 'a).{set : ('a) -> unit}) -> () -> 'b

Arguments:

(unlabeled) (of type ('a) -> 'b): Function to apply to the getter.
(unlabeled) (of type ('b) -> 'a): Function to apply to the setter.
(unlabeled) (of type (() -> 'a).{set : ('a) -> unit})

Methods:

set (of type ('A) -> unit): Set the value of the reference.

`snd`

Get the second component of a pair.

Type:

(('a * 'b)) -> 'b

Arguments:

(unlabeled) (of type 'a * 'b)

`thread.on_error`

Register the function to be called when an error of the given kind is raised in a thread. Catches all errors if first argument is null.

Type:

(error
 .{
   kind : string,
   message : string,
   trace : [
            {
              position_end : 
              {character_offset : int, filename : string, line_number : int
              },
              position_start : 
              {character_offset : int, filename : string, line_number : int
              },
              to_string : (?prefix : string) -> string
            }]
 }?,
 ((backtrace : string, error
   .{
     kind : string,
     message : string,
     trace : [
              {
                position_end : 
                {character_offset : int, filename : string, line_number : int
                },
                position_start : 
                {character_offset : int, filename : string, line_number : int
                },
                to_string : (?prefix : string) -> string
              }]
   }) -> unit)) -> unit

Arguments:

(unlabeled) (of type error .{ kind : string, message : string, trace : [ { position_end : {character_offset : int, filename : string, line_number : int }, position_start : {character_offset : int, filename : string, line_number : int }, to_string : (?prefix : string) -> string }] }?)
(unlabeled) (of type (backtrace : string, error .{ kind : string, message : string, trace : [ { position_end : {character_offset : int, filename : string, line_number : int }, position_start : {character_offset : int, filename : string, line_number : int }, to_string : (?prefix : string) -> string }] }) -> unit)

`thread.pause`

Pause execution for a given amount of seconds. This freezes the calling thread and should not be used in the main streaming loop.

Type:

(float) -> unit

Arguments:

(unlabeled) (of type float): Number of seconds of pause.

`thread.run`

Run a function in a separate thread.

Type:

(?fast : bool, ?delay : float, ?every : {float}?, (() -> unit)) -> unit

Arguments:

fast (of type bool, which defaults to true): Whether the thread is supposed to return quickly or not. Typically, blocking tasks (e.g. fetching data over the internet) should not be considered to be fast. When set to false its priority will be lowered below that of request resolutions and fast timeouts. This is only effective if you set a dedicated queue for fast tasks, see the “scheduler” settings for more details.
delay (of type float, which defaults to 0.): Delay (in seconds) after which the thread should be launched.
every (of type {float}?, which defaults to null): How often (in seconds) the thread should be run. If negative or null, run once.
(unlabeled) (of type () -> unit): Function to execute.

`thread.run.recurrent`

Run a recurrent function in a separate thread.

Type:

(?fast : bool, ?delay : float, (() -> float)) -> unit

Arguments:

fast (of type bool, which defaults to true): Whether the thread is supposed to return quickly or not. Typically, blocking tasks (e.g. fetching data over the internet) should not be considered to be fast. When set to false its priority will be lowered below that of request resolutions and fast timeouts. This is only effective if you set a dedicated queue for fast tasks, see the “scheduler” settings for more details.
delay (of type float, which defaults to 0.): Delay (in sec.) after which the thread should be launched.
(unlabeled) (of type () -> float): Function to execute recurrently. The returned value is the delay (in sec.) in which the function should be run again (it won’t be run if the value is strictly negative).

`thread.when`

Execute a callback when a predicate is true. The predicate is checked every seconds and the callback is called when the predicate returns true after having been false, following the same semantics as predicate.activates.

Type:

(?fast : bool, ?init : bool, ?every : {float}, ?once : bool, ?changed : bool,
 (() -> bool), (() -> 'a)) -> unit

Arguments:

fast (of type bool, which defaults to true): Whether the callback is supposed to return quickly or not.
init (of type bool, which defaults to true): Detect at beginning.
every (of type {float}, which defaults to 0.5): How often (in sec.) to check for the predicate.
once (of type bool, which defaults to false): Execute the function only once.
changed (of type bool, which defaults to true): Execute the function only if the predicate was false when last checked.
(unlabeled) (of type () -> bool): Predicate indicating when to execute the function, typically a time interval such as {10h-10h30}.
(unlabeled) (of type () -> 'a): Function to execute when the predicate is true.

`while`

A while loop.

Type:

({bool}, (() -> unit)) -> unit

Arguments:

(unlabeled) (of type {bool}): Condition guarding the loop.
(unlabeled) (of type () -> unit): Function to execute.

Settings

`audio.channels`

Channels for audio.

Type:

() -> int

`audio.samplerate`

Samplerate for audio.

Type:

() -> int

`frame.duration`

Duration of a frame.

Type:

() -> float

Source / Audio processing

`add`

Mix sources, with optional normalization. Only relay metadata from the first available source. Track marks are dropped from all sources.

Type:

(?id : string?, ?normalize : {bool}, ?power : {bool}, ?weights : [{float}],
 [source('a)]) -> source('a)
where 'a is a set of internal tracks

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
normalize (of type {bool}, which defaults to true): Divide by the sum of weights of ready sources (or by the number of ready sources if weights are not specified).
power (of type {bool}, which defaults to false): Perform constant-power normalization.
weights (of type [{float}], which defaults to []): Relative weight of the sources in the sum. The empty list stands for the homogeneous distribution. These are used as amplification coefficients if we are not normalizing.
(unlabeled) (of type [source('a)] where 'a is a set of internal tracks)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`amplify`

Multiply the amplitude of the signal.

Type:

(?id : string?, ?override : string?, {float}, source(audio=pcm('a), 'b)) ->
source(audio=pcm('a), 'b)
where 'b is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to "amplify"): Force the value of the track ID.
override (of type string?, which defaults to "liq_amplify"): Specify the name of a metadata field that, when present and well-formed, overrides the amplification factor for the current track. Well-formed values are floats in decimal notation (e.g. 0.7) which are taken as normal/linear multiplicative factors; values can be passed in decibels with the suffix dB (e.g. -8.2 dB, but the spaces do not matter).
(unlabeled) (of type {float}): Multiplicative factor.
(unlabeled) (of type source(audio=pcm('a), 'b) where 'b is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`audio.decode.pcm_f32`

Decode audio track to pcm_f32

Type:

(?id : string?, source(audio=pcm_f32('a), 'b)) -> source(audio=pcm('a), 'b)
where 'b is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to "audio.decode.pcm_f32")
(unlabeled) (of type source(audio=pcm_f32('a), 'b) where 'b is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`audio.decode.pcm_s16`

Decode audio track to pcm_s16

Type:

(?id : string?, source(audio=pcm_s16('a), 'b)) -> source(audio=pcm('a), 'b)
where 'b is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to "audio.decode.pcm_s16")
(unlabeled) (of type source(audio=pcm_s16('a), 'b) where 'b is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`audio.encode.pcm_f32`

Encode audio track to pcm_f32

Type:

(?id : string?, source(audio=pcm('a), 'b)) -> source(audio=pcm_f32('a), 'b)
where 'b is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to "audio.encode.pcm_f32")
(unlabeled) (of type source(audio=pcm('a), 'b) where 'b is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`audio.encode.pcm_s16`

Encode audio track to pcm_s16

Type:

(?id : string?, source(audio=pcm('a), 'b)) -> source(audio=pcm_s16('a), 'b)
where 'b is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to "audio.encode.pcm_s16")
(unlabeled) (of type source(audio=pcm('a), 'b) where 'b is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`clip`

Clip samples, i.e. ensure that all values are between -1 and 1: values lower than -1 become -1 and values higher than 1 become 1. nan values become 0.

Type:

(?id : string?, source(audio=pcm('a), 'b)) -> source(audio=pcm('a), 'b)
where 'b is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to "clip"): Force the value of the track ID.
(unlabeled) (of type source(audio=pcm('a), 'b) where 'b is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`delay_line`

Delay the audio signal by a given amount of time.

Type:

(?id : string?, {float}, source(audio=pcm('a), 'b)) -> source(audio=pcm('a),
'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
(unlabeled) (of type {float}): Duration of the delay in seconds.
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`dtmf.detect`

Detect DTMF tones.

Type:

(?id : string?, ?bands : int, ?debug : {bool}, ?duration : {float},
 ?smoothing : {float}, ?threshold : {float}, source(audio=pcm('a), 'b),
 ((string) -> unit)) -> source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
bands (of type int, which defaults to 1024): Number of frequency bands.
debug (of type {bool}, which defaults to false): Show internal values on standard output in order to fine-tune parameters: band number, band frequency, detected intensity and smoothed intensity.
duration (of type {float}, which defaults to 0.05): Duration for detecting a tone.
smoothing (of type {float}, which defaults to 0.01): Smoothing time (in seconds) for band indensity (the higher, the less sensitive we are to local variations, but the more time we take to detect a band).
threshold (of type {float}, which defaults to 50.): Threshold for detecting a band.
(unlabeled) (of type source(audio=pcm('a), 'b)): Source on which DTMF tones should be detected.
(unlabeled) (of type (string) -> unit): Function called with detected key as argument.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`echo`

Add echo.

Type:

(?id : string?, ?delay : {float}, ?feedback : {float}, ?ping_pong : bool,
 source(audio=pcm('a), 'b)) -> source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
delay (of type {float}, which defaults to 0.5): Delay in seconds.
feedback (of type {float}, which defaults to -6.): Feedback coefficient in dB (negative).
ping_pong (of type bool, which defaults to false): Use ping-pong delay.
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`filter`

Perform several kinds of filtering on the signal. Only frequencies below the sampling rate / 4 (generally 10 kHz) are handled well for the freq parameter.

Type:

(?id : string?, freq : {float}, mode : string, ?q : {float},
 ?wetness : {float}, source(audio=pcm('a), 'b)) -> source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
freq (of type {float}): Characteristic frequency of the filter.
mode (of type string): Available modes are ‘low’ (for low-pass filter), ‘high’ (for high-pass filter), ‘band’ (for band-pass filter) and ‘notch’ (for notch / band-stop / band-rejection filter).
q (of type {float}, which defaults to 1.)
wetness (of type {float}, which defaults to 1.): How much of the original signal should be added (1. means only filtered and 0. means only original signal).
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`filter.fir`

Low-pass FIR filter.

Type:

(?id : string?, beta : float, ?coeffs : int, frequency : float,
 source(audio=pcm('a), 'b)) -> source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
beta (of type float): Beta should range between 0 and 1.
coeffs (of type int, which defaults to 255): Number of coefficients
frequency (of type float): Corner frequency in Hz (frequency at which the response is 0.5, that is -6 dB).
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`filter.iir.butterworth.bandpass`

IIR filter

Type:

(?id : string?, frequency1 : float, frequency2 : float, ?order : int,
 source(audio=pcm('a), 'b)) -> source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
frequency1 (of type float): First corner frequency
frequency2 (of type float): Second corner frequency
order (of type int, which defaults to 4): Filter order
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`filter.iir.butterworth.bandstop`

IIR filter

Type:

(?id : string?, frequency1 : float, frequency2 : float, ?order : int,
 source(audio=pcm('a), 'b)) -> source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
frequency1 (of type float): First corner frequency
frequency2 (of type float): Second corner frequency
order (of type int, which defaults to 4): Filter order
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`filter.iir.butterworth.high`

IIR filter

Type:

(?id : string?, frequency : float, ?order : int, source(audio=pcm('a), 'b)) ->
source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
frequency (of type float): Corner frequency
order (of type int, which defaults to 4): Filter order
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`filter.iir.butterworth.low`

IIR filter

Type:

(?id : string?, frequency : float, ?order : int, source(audio=pcm('a), 'b)) ->
source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
frequency (of type float): Corner frequency
order (of type int, which defaults to 4): Filter order
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`filter.iir.eq.allpass`

All-pass biquad filter.

Type:

(?id : string?, ?bandwidth : {float}, frequency : {float}, source('a)) ->
source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
bandwidth (of type {float}, which defaults to 0.333333333333): Bandwidth (in octaves)
frequency (of type {float}): Center frequency
(unlabeled) (of type source('a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`filter.iir.eq.bandpass`

Band-pass biquad filter.

Type:

(?id : string?, frequency : {float}, ?q : {float}, source('a)) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
frequency (of type {float}): Center frequency
q (of type {float}, which defaults to 1.): Q
(unlabeled) (of type source('a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`filter.iir.eq.high`

High-pass biquad filter.

Type:

(?id : string?, frequency : {float}, ?q : {float}, source('a)) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
frequency (of type {float}): Corner frequency
q (of type {float}, which defaults to 1.): Q
(unlabeled) (of type source('a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`filter.iir.eq.highshelf`

High shelf biquad filter.

Type:

(?id : string?, frequency : {float}, ?slope : {float}, source('a)) ->
source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
frequency (of type {float}): Center frequency
slope (of type {float}, which defaults to 1.): Shelf slope (in dB/octave)
(unlabeled) (of type source('a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`filter.iir.eq.low`

Low-pass biquad filter.

Type:

(?id : string?, frequency : {float}, ?q : {float}, source('a)) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
frequency (of type {float}): Corner frequency
q (of type {float}, which defaults to 1.): Q
(unlabeled) (of type source('a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`filter.iir.eq.lowshelf`

Low shelf biquad filter.

Type:

(?id : string?, frequency : {float}, ?slope : {float}, source('a)) ->
source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
frequency (of type {float}): Corner frequency
slope (of type {float}, which defaults to 1.): Shelf slope (dB/octave)
(unlabeled) (of type source('a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`filter.iir.eq.notch`

Band-pass biquad filter.

Type:

(?id : string?, frequency : {float}, ?q : {float}, source('a)) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
frequency (of type {float}): Center frequency
q (of type {float}, which defaults to 1.): Q
(unlabeled) (of type source('a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`filter.iir.eq.peak`

Peak EQ biquad filter.

Type:

(?id : string?, frequency : {float}, ?gain : {float}, ?q : {float},
 source('a)) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
frequency (of type {float}): Center frequency
gain (of type {float}, which defaults to 1.): Gain (in dB)
q (of type {float}, which defaults to 1.): Q
(unlabeled) (of type source('a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`filter.iir.resonator.allpass`

IIR filter

Type:

(?id : string?, frequency : float, ?q : float, source(audio=pcm('a), 'b)) ->
source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
frequency (of type float): Corner frequency
q (of type float, which defaults to 60.): Quality factor
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`filter.iir.resonator.bandpass`

IIR filter

Type:

(?id : string?, frequency : float, ?q : float, source(audio=pcm('a), 'b)) ->
source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
frequency (of type float): Corner frequency
q (of type float, which defaults to 60.): Quality factor
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`filter.iir.resonator.bandstop`

IIR filter

Type:

(?id : string?, frequency : float, ?q : float, source(audio=pcm('a), 'b)) ->
source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
frequency (of type float): Corner frequency
q (of type float, which defaults to 60.): Quality factor
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`filter.rc`

First-order filter (RC filter).

Type:

(?id : string?, frequency : {float}, mode : string, ?wetness : {float},
 source(audio=pcm('a), 'b)) -> source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
frequency (of type {float}): Cutoff frequency.
mode (of type string): Available modes are ‘low’ (for low-pass filter), ‘high’ (for high-pass filter).
wetness (of type {float}, which defaults to 1.): How much of the original signal should be added (1. means only filtered and 0. means only original signal).
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`flanger`

Flanger effect.

Type:

(?id : string?, ?delay : float, ?feedback : {float}, ?freq : {float},
 ?phase : {float}, source(audio=pcm('a), 'b)) -> source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
delay (of type float, which defaults to 0.001): Delay in seconds.
feedback (of type {float}, which defaults to 0.): Feedback coefficient in dB.
freq (of type {float}, which defaults to 0.5): Frequency in Hz.
phase (of type {float}, which defaults to 1.): Phase difference between channels in radians.
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`gate`

Reduce the volume when the stream is silent (typically in order to avoid low intensity noise).

Type:

(?id : string?, ?attack : {float}, ?hold : {float}, ?range : {float},
 ?release : {float}, ?threshold : {float}, ?window : {float},
 source(audio=pcm('a), 'b)) -> source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
attack (of type {float}, which defaults to 10.): Time to fully open the gate (ms).
hold (of type {float}, which defaults to 1000.): Minimum amount of time the gate stays open (ms).
range (of type {float}, which defaults to -30.): Difference between closed and open level (dB).
release (of type {float}, which defaults to 2000.): Time to fully close the gate (ms).
threshold (of type {float}, which defaults to -30.): Threshold at which the gate will open (dB).
window (of type {float}, which defaults to 1.): Duration for computing peak (ms).
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
gate (of type () -> float): Position of the gate (0. means closed, 1. means open).
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`normalize`

Normalization the volume of a stream (this is also called automatic gain control). Dynamic normalization of the signal is sometimes the only option (for instance, for live sources), and can make a listening experience much nicer. However, its dynamic aspect implies some limitations which can go as far as creating saturation in some extreme cases. If possible, consider using some track-based normalization techniques such as those based on ReplayGain. The implementation of Liquidsoap < 2.0 was renamed to normalize.old.

Type:

(?id : string?, ?target : {float}, ?up : {float}, ?down : {float},
 ?gain_min : float, ?gain_max : float, ?lufs : bool, ?lookahead : {float},
 ?window : {float}, ?threshold : {float}, ?track_sensitive : bool,
 ?debug : float??, source(audio=pcm('a), 'b)) -> source(audio=pcm('a), 'b)
where 'b is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
target (of type {float}, which defaults to -13.): Desired RMS (dB).
up (of type {float}, which defaults to 10.): Characteristic time to go up.
down (of type {float}, which defaults to 0.1): Characteristic time to go down.
gain_min (of type float, which defaults to -12.): Minimal gain value (dB).
gain_max (of type float, which defaults to 12.): Maximal gain value (dB).
lufs (of type bool, which defaults to false): Use LUFS instead of RMS to compute intensity.
lookahead (of type {float}, which defaults to 0.): How much time to look ahead of the signal (second). Setting a positive value delays the output by the corresponding amount of time.
window (of type {float}, which defaults to 0.5): Duration of the window used to compute the current RMS power (second).
threshold (of type {float}, which defaults to -40.): Minimal RMS for activaing gain control (dB).
track_sensitive (of type bool, which defaults to true)
debug (of type float??, which defaults to null): How often to print debug messages, in seconds, useful to finetune the parameters. You should set set("log.level", 5) to see them.
(unlabeled) (of type source(audio=pcm('a), 'b) where 'b is a set of tracks to be muxed into a source): Source to normalize.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
gain (of type () -> float): Current amplification coefficient (in linear scale).
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
rms (of type () -> float): Current rms (in linear scale).
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
target_gain (of type () -> float): Current target amplification coefficient (in linear scale).
time (of type () -> float): Get a source’s time, based on its assigned clock.

`normalize.old`

Normalize the signal. Dynamic normalization of the signal is sometimes the only option, and can make a listening experience much nicer. However, its dynamic aspect implies some limitations which can go as far as creating saturation in some extreme cases. If possible, consider using some track-based normalization techniques such as those based on replay gain. See the documentation for more details. This is the implementation provided in Liquidsoap < 2.0. A new, better and more customizable one is now given in normalize.

Type:

(?id : string?, ?gain_max : {float}, ?gain_min : {float}, ?k_down : {float},
 ?k_up : {float}, ?target : {float}, ?threshold : {float},
 ?track_sensitive : bool, ?window : float, source(audio=pcm('a), 'b)) ->
source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
gain_max (of type {float}, which defaults to 6.): Maximal gain value (dB).
gain_min (of type {float}, which defaults to -6.): Minimal gain value (dB).
k_down (of type {float}, which defaults to 0.1): Coefficient when the power must go down (between 0 and 1, slowest to fastest).
k_up (of type {float}, which defaults to 0.005): Coefficient when the power must go up (between 0 and 1, slowest to fastest).
target (of type {float}, which defaults to -13.): Desired RMS (dB).
threshold (of type {float}, which defaults to -40.): Minimal RMS for activaing gain control (dB).
track_sensitive (of type bool, which defaults to true): Reset values on every track.
window (of type float, which defaults to 0.1): Duration of the window used to compute the current RMS power (second).
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
gain (of type () -> float): Current amplification coefficient.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
rms (of type () -> float): Current RMS.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`peak`

Get current peak volume of the source. Returns the source with a method peak to compute the current peak volume of the source, with 0.0 <= peak volume <= 1.0.

Type:

(?id : string?, ?duration : {float}, source(audio=pcm('a), 'b)) ->
source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
duration (of type {float}, which defaults to 0.5): Duration of the window (in seconds). A value <= 0, means that computation should not be performed.
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
peak (of type () -> float): Current value for the peak volume.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`peak.stereo`

Get current peak volume of the source. Returns the source with a method peak to compute the current peak volume of the source, with 0.0 <= peak volume <= 1.0.

Type:

(?id : string?, ?duration : {float}, source(audio=pcm(stereo), 'a)) ->
source(audio=pcm(stereo), 'a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
duration (of type {float}, which defaults to 0.5): Duration of the window (in seconds). A value <= 0, means that computation should not be performed.
(unlabeled) (of type source(audio=pcm(stereo), 'a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
peak (of type () -> float * float): Current value for the peak volume.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`pipe`

Process audio signal through a given process stdin/stdout.

Type:

(?id : string?, ?buffer : float, ?data_length : int?, ?max : float,
 process : string, ?replay_delay : float?, ?restart : bool,
 ?restart_on_error : bool, source(audio=pcm('a), 'b)) ->
source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
buffer (of type float, which defaults to 1.): Duration of the pre-buffered data.
data_length (of type int?, which defaults to null): Length passed in the WAV data chunk. Data is streamed so no the consuming program should process it as it comes. Some program operate better when this value is set to 0, some other when it is set to the maximum length allowed by the WAV specs. Use any negative value to set to maximum length.
max (of type float, which defaults to 10.): Maximum duration of the buffered data.
process (of type string): Process used to pipe data to.
replay_delay (of type float?, which defaults to null): Replay track marks and metadata from the input source on the output after a given delay. If null (default) close and flush the process on each track and metadata to get an exact timing. This parameter is typically used when integrating with stereotool.
restart (of type bool, which defaults to true): Restart process when exited.
restart_on_error (of type bool, which defaults to true): Restart process when exited with error.
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`replaygain`

Amplify source tracks according to replaygain metadata. This operator does not compute itself the replaygain: you can use either enable_replaygain_metadata or the replaygain: protocol for this.

Type:

(?id : string?, ?ebu_r128 : bool, source(audio=pcm('a), 'b)) ->
source(audio=pcm('a), 'b)
where 'b is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
ebu_r128 (of type bool, which defaults to true): Also amplify according to EBU R128 tags.
(unlabeled) (of type source(audio=pcm('a), 'b) where 'b is a set of tracks to be muxed into a source): Source to be amplified.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`rms`

Get current RMS volume of the source. Returns the source with a method rms to compute the current RMS volume of the source, with 0.0 <= RMS volume <= 1.0.

Type:

(?id : string?, ?duration : {float}, source(audio=pcm('a), 'b)) ->
source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
duration (of type {float}, which defaults to 0.5): Duration of the window (in seconds). A value <= 0, means that computation should not be performed.
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
rms (of type () -> float): Current value for the RMS volume.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`rms.stereo`

Get current RMS volume of the source. Returns the source with a method rms to compute the current RMS volume of the source, with 0.0 <= RMS volume <= 1.0.

Type:

(?id : string?, ?duration : {float}, source(audio=pcm(stereo), 'a)) ->
source(audio=pcm(stereo), 'a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
duration (of type {float}, which defaults to 0.5): Duration of the window (in seconds). A value <= 0, means that computation should not be performed.
(unlabeled) (of type source(audio=pcm(stereo), 'a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
rms (of type () -> float * float): Current value for the RMS volume.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`sine.detect`

Detect sine waves.

Type:

(?id : string?, ?bands : int, ?debug : {bool}, ?duration : {float},
 ?smoothing : {float}, ?threshold : {float}, [float], source(audio=pcm('a),
 'b), ((float) -> unit)) -> source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
bands (of type int, which defaults to 1024): Number of frequency bands.
debug (of type {bool}, which defaults to false): Show internal values on standard output in order to fine-tune parameters: band number, band frequency, detected intensity and smoothed intensity.
duration (of type {float}, which defaults to 0.5): Duration for detecting a tone.
smoothing (of type {float}, which defaults to 0.01): Smoothing time (in seconds) for band indensity (the higher, the less sensitive we are to local variations, but the more time we take to detect a band).
threshold (of type {float}, which defaults to 50.): Threshold for detecting a band.
(unlabeled) (of type [float]): List of frequencies to detect.
(unlabeled) (of type source(audio=pcm('a), 'b)): Source on which sines should be detected.
(unlabeled) (of type (float) -> unit): Function called with detected frequency as argument.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`soundtouch`

Change the rate, the tempo or the pitch of the sound.

Type:

(?id : string?, ?pitch : {float}, ?rate : {float}, ?tempo : {float},
 source(audio=pcm('a), 'b)) -> source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
pitch (of type {float}, which defaults to 1.)
rate (of type {float}, which defaults to 1.)
tempo (of type {float}, which defaults to 1.)
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

This function is experimental.

`source.replaygain.compute`

Compute the ReplayGain of the source. Data is accumulated until the gain method is called, i.e. the gain is computed after the source has been played..

Type:

(?id : string?, source(audio=pcm('a), 'b)) -> source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
gain (of type () -> float): Suggested gain (in dB).
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
peak (of type () -> float): Peak sample.
remaining (of type () -> float): Estimation of remaining time in the current track.
reset (of type () -> unit): Reset ReplayGain computation.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`stereo.ms.decode`

Decode mid+side stereo (M/S) to left+right stereo.

Type:

(?id : string?, ?width : float, source(audio=pcm(stereo), 'a)) ->
source(audio=pcm(stereo), 'a)
where 'a is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to "stereo.ms.decode"): Force the value of the track ID.
width (of type float, which defaults to 1.): Width of the stereo field.
(unlabeled) (of type source(audio=pcm(stereo), 'a) where 'a is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`stereo.ms.encode`

Encode left+right stereo to mid+side stereo (M/S).

Type:

(?id : string?, source(audio=pcm(stereo), 'a)) -> source(audio=pcm(stereo),
'a) where 'a is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to "stereo.ms.encode"): Force the value of the track ID.
(unlabeled) (of type source(audio=pcm(stereo), 'a) where 'a is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`stereo.pan`

Pan a stereo sound.

Type:

(?id : string?, ?pan : {float}, ?field : {float}, source(audio=pcm(stereo),
 'a)) -> source(audio=pcm(stereo), 'a)
where 'a is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to "stereo.pan"): Force the value of the track ID.
pan (of type {float}, which defaults to 0.): Pan ranges between -1 and 1.
field (of type {float}, which defaults to 90.): Field width in degrees (between 0 and 90).
(unlabeled) (of type source(audio=pcm(stereo), 'a) where 'a is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`stereo.width`

Spacializer which allows controlling the width of the signal.

Type:

(?id : string?, ?{float}, source(audio=pcm(stereo), 'a)) ->
source(audio=pcm(stereo), 'a)
where 'a is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to "stereo.width")
(unlabeled) (of type {float}, which defaults to 0.): Width of the signal (-1: mono, 0.: original, 1.: wide stereo).
(unlabeled) (of type source(audio=pcm(stereo), 'a) where 'a is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`stereotool`

Process an audio source using stereotool

Type:

(?id : string?, library_file : string, ?license_key : string?,
 ?preset : string?, ?load_type : string, source(audio=pcm('a), 'b)) ->
source(audio=pcm('a))

Arguments:

id (of type string?, which defaults to "stereotool"): Force the value of the track ID.
library_file (of type string): Path to the shared library file.
license_key (of type string?, which defaults to null)
preset (of type string?, which defaults to null): Path to a preset file to load when initializing the operator.
load_type (of type string, which defaults to "totalinit"): Load type for preset. One of: “totalinit”, “all_settings”, “audiofm”, “audio”, “processing”, “repair”, “repair_no_pnr” or “sublevel_pnr”.
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

api_version (of type () -> int): API version.
buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
latency (of type () -> float): Get the operator’s latency.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
software_version (of type () -> int): Software version.
time (of type () -> float): Get a source’s time, based on its assigned clock.
unlincensed_used_features (of type () -> string?): Check if the license is valid for the current settings.
valid_license (of type () -> bool): Check if the license is valid for the current settings.

`stretch`

Slow down or accelerate an audio stream by stretching (sounds lower) or squeezing it (sounds higher).

Type:

(?id : string?, ratio : {float}, source(audio=pcm('a), 'b)) ->
source(audio=pcm('a))

Arguments:

id (of type string?, which defaults to "stretch"): Force the value of the track ID.
ratio (of type {float}): A value higher than 1 means slowing down.
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

Source / Conversion

`ffmpeg.decode.audio`

Decode a source’s audio content

Type:

(?id : string?, source(audio=ffmpeg.copy('a), 'b)) -> source(audio=pcm('c))

Arguments:

id (of type string?, which defaults to "ffmpeg.decode.audio")
(unlabeled) (of type source(audio=ffmpeg.copy('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`ffmpeg.decode.audio_video`

Decode a source’s audio and video content

Type:

(?id : string?, source(audio=ffmpeg.copy('b), video=ffmpeg.copy('a))) ->
source(audio=pcm('c), video=canvas('d))

Arguments:

id (of type string?, which defaults to "ffmpeg.decode.audio_video")
(unlabeled) (of type source(audio=ffmpeg.copy('b), video=ffmpeg.copy('a)))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`ffmpeg.decode.video`

Decode a source’s video content

Type:

(?id : string?, source(video=ffmpeg.copy('a), 'b)) ->
source(video=canvas('c))

Arguments:

id (of type string?, which defaults to "ffmpeg.decode.video")
(unlabeled) (of type source(video=ffmpeg.copy('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`ffmpeg.encode.audio`

Encode a source’s audio content

Type:

(?id : string?, format(audio=pcm('a), 'b), source(audio=pcm('a), 'c)) ->
source(audio=ffmpeg.copy('d))

Arguments:

id (of type string?, which defaults to "ffmpeg.encode.audio")
(unlabeled) (of type format(audio=pcm('a), 'b))
(unlabeled) (of type source(audio=pcm('a), 'c))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`ffmpeg.encode.audio_video`

Encode a source’s audio and video content

Type:

(?id : string?, format(audio=pcm('a), video=canvas('b), 'c),
 source(audio=pcm('a), video=canvas('b))) -> source(audio=ffmpeg.copy('d),
video=ffmpeg.copy('e))

Arguments:

id (of type string?, which defaults to "ffmpeg.encode.audio_video")
(unlabeled) (of type format(audio=pcm('a), video=canvas('b), 'c))
(unlabeled) (of type source(audio=pcm('a), video=canvas('b)))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`ffmpeg.encode.video`

Encode a source’s video content

Type:

(?id : string?, format(video=canvas('a), 'b), source(video=canvas('a), 'c)) ->
source(video=ffmpeg.copy('d))

Arguments:

id (of type string?, which defaults to "ffmpeg.encode.video")
(unlabeled) (of type format(video=canvas('a), 'b))
(unlabeled) (of type source(video=canvas('a), 'c))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`ffmpeg.raw.decode.audio`

Decode a source’s audio content

Type:

(?id : string?, source(audio=ffmpeg.audio.raw('a), 'b)) ->
source(audio=pcm('c))

Arguments:

id (of type string?, which defaults to "ffmpeg.raw.decode.audio")
(unlabeled) (of type source(audio=ffmpeg.audio.raw('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`ffmpeg.raw.decode.audio_video`

Decode a source’s audio and video content

Type:

(?id : string?, source(audio=ffmpeg.audio.raw('b),
 video=ffmpeg.video.raw('a))) -> source(audio=pcm('c), video=canvas('d))

Arguments:

id (of type string?, which defaults to "ffmpeg.raw.decode.audio_video")
(unlabeled) (of type source(audio=ffmpeg.audio.raw('b), video=ffmpeg.video.raw('a)))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`ffmpeg.raw.decode.video`

Decode a source’s video content

Type:

(?id : string?, source(video=ffmpeg.video.raw('a), 'b)) ->
source(video=canvas('c))

Arguments:

id (of type string?, which defaults to "ffmpeg.raw.decode.video")
(unlabeled) (of type source(video=ffmpeg.video.raw('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`ffmpeg.raw.encode.audio`

Encode a source’s audio content

Type:

(?id : string?, format(audio=ffmpeg.audio.raw('a), 'b), source(audio=pcm('c),
 'd)) -> source(audio=ffmpeg.audio.raw('a))

Arguments:

id (of type string?, which defaults to "ffmpeg.raw.encode.audio")
(unlabeled) (of type format(audio=ffmpeg.audio.raw('a), 'b))
(unlabeled) (of type source(audio=pcm('c), 'd))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`ffmpeg.raw.encode.audio_video`

Encode a source’s audio and video content

Type:

(?id : string?, format(audio=ffmpeg.audio.raw('a),
 video=ffmpeg.video.raw('b), 'c), source(audio=pcm('e), video=canvas('d))) ->
source(audio=ffmpeg.audio.raw('a), video=ffmpeg.video.raw('b))

Arguments:

id (of type string?, which defaults to "ffmpeg.raw.encode.audio_video")
(unlabeled) (of type format(audio=ffmpeg.audio.raw('a), video=ffmpeg.video.raw('b), 'c))
(unlabeled) (of type source(audio=pcm('e), video=canvas('d)))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`ffmpeg.raw.encode.video`

Encode a source’s video content

Type:

(?id : string?, format(video=ffmpeg.video.raw('a), 'b),
 source(video=canvas('c), 'd)) -> source(video=ffmpeg.video.raw('a))

Arguments:

id (of type string?, which defaults to "ffmpeg.raw.encode.video")
(unlabeled) (of type format(video=ffmpeg.video.raw('a), 'b))
(unlabeled) (of type source(video=canvas('c), 'd))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`mean`

Produce mono audio by taking the mean of all audio channels.

Type:

(?id : string?, ?normalize : bool, source(audio=pcm('a), 'b)) ->
source(audio=pcm(mono), 'b)
where 'b is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to "mean"): Force the value of the track ID.
normalize (of type bool, which defaults to true): Divide the output volume by the number of channels.
(unlabeled) (of type source(audio=pcm('a), 'b) where 'b is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`stereo`

Convert any pcm audio source into a stereo source.

Type:

(?id : string?, source(audio=pcm('a), 'b)) -> source(audio=pcm(stereo), 'b)
where 'b is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to "stereo")
(unlabeled) (of type source(audio=pcm('a), 'b) where 'b is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`stereo.left`

Extract the left channel of a stereo source

Type:

(?id : string?, source(audio=pcm(stereo), 'a)) -> source(audio=pcm(mono), 'a)
where 'a is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to "stereo.left")
(unlabeled) (of type source(audio=pcm(stereo), 'a) where 'a is a set of tracks to be muxed into a source): Source to extract from

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`stereo.right`

Extract the right channel of a stereo source

Type:

(?id : string?, source(audio=pcm(stereo), 'a)) -> source(audio=pcm(mono), 'a)
where 'a is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to "stereo.right")
(unlabeled) (of type source(audio=pcm(stereo), 'a) where 'a is a set of tracks to be muxed into a source): Source to extract from

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`swap`

Swap two channels of a stereo source.

Type:

(?string?, source(audio=pcm(stereo), 'a)) -> source(audio=pcm(stereo), 'a)
where 'a is a set of tracks to be muxed into a source

Arguments:

(unlabeled) (of type string?, which defaults to "swap")
(unlabeled) (of type source(audio=pcm(stereo), 'a) where 'a is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`track.audio.stereo.left`

Extract the left channel of a stereo track

Type:

(?id : string?, pcm(stereo)) -> pcm(mono)

Arguments:

id (of type string?, which defaults to "track.audio.stereo.left")
(unlabeled) (of type pcm(stereo)): Track to extract from

`track.audio.stereo.right`

Extract the right channel of a stereo track

Type:

(?id : string?, pcm(stereo)) -> pcm(mono)

Arguments:

id (of type string?, which defaults to "track.audio.stereo.right")
(unlabeled) (of type pcm(stereo)): Track to extract from

Source / FFmpeg filter

`ffmpeg.filter.audio.input`

Attach an audio track to a filter’s input

Type:

(?id : string?, ?pass_metadata : bool, ffmpeg.filter.graph,
 ffmpeg.audio.raw('a)) -> ffmpeg.filter.audio

Arguments:

id (of type string?, which defaults to null)
pass_metadata (of type bool, which defaults to true): Pass liquidsoap’s metadata to this stream
(unlabeled) (of type ffmpeg.filter.graph)
(unlabeled) (of type ffmpeg.audio.raw('a))

`ffmpeg.filter.create`

Configure and launch a filter graph

Type:

(((ffmpeg.filter.graph) -> 'a)) -> 'a

Arguments:

(unlabeled) (of type (ffmpeg.filter.graph) -> 'a)

`ffmpeg.filter.video.input`

Attach a video track to a filter’s input

Type:

(?id : string?, ?pass_metadata : bool, ffmpeg.filter.graph,
 ffmpeg.video.raw('a)) -> ffmpeg.filter.video

Arguments:

id (of type string?, which defaults to null)
pass_metadata (of type bool, which defaults to true): Pass liquidsoap’s metadata to this stream
(unlabeled) (of type ffmpeg.filter.graph)
(unlabeled) (of type ffmpeg.video.raw('a))

Source / Fade

`cross`

Cross operator, allowing the composition of the n last seconds of a track with the beginning of the next track, using a transition function depending on the relative power of the signal before and after the end of track.

Type:

(?id : string?, ?conservative : bool, ?duration : {float}, ?minimum : float,
 ?override_duration : string, ?persist_override : bool, ?width : float,
 ((
   {
     db_level : float,
     metadata : [string * string],
     source : source(audio=pcm('a),
     'b)
   }, 
   {
     db_level : float,
     metadata : [string * string],
     source : source(audio=pcm('a),
     'b)
   }) -> source(audio=pcm('a), 'b)),
 source(audio=pcm('a), 'b)) -> source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
conservative (of type bool, which defaults to true): Do not trust remaining time estimations, always buffering data in advance. This avoids being tricked by skips, either manual or caused by blank.skip().
duration (of type {float}, which defaults to 5.): Duration (in seconds) of buffered data from each track that is used to compute the transition between tracks.
minimum (of type float, which defaults to -1.): Minimum duration (in sec.) for a cross: If the track ends without any warning (e.g. in case of skip) there may not be enough data for a decent composition. Set to 0. to avoid having transitions after skips, or more to avoid transitions on short tracks. With a negative default, transitions always occur.
override_duration (of type string, which defaults to "liq_cross_duration"): Metadata field which, if present and containing a float, overrides the ‘duration’ parameter for current track.
persist_override (of type bool, which defaults to false): Keep duration override on track change.
width (of type float, which defaults to 2.): Width of the power computation window.
(unlabeled) (of type ( { db_level : float, metadata : [string * string], source : source(audio=pcm('a), 'b) }, { db_level : float, metadata : [string * string], source : source(audio=pcm('a), 'b) }) -> source(audio=pcm('a), 'b)): Transition function, composing from the end of a track and the next track. The sources corresponding to the two tracks are decorated with fields indicating the power of the signal before and after the transition (power), and the metadata (metadata).
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
cross_duration (of type () -> float): Get the current crossfade duration.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`cross.simple`

Simple transition for crossfade

Type:

(?fade_in : float, ?fade_out : float, source(audio=pcm('a), 'b),
 source(audio=pcm('a), 'b)) -> source(audio=pcm('a), 'b)
where
  'b is a set of tracks to be muxed into a source and a set of internal tracks

Arguments:

fade_in (of type float, which defaults to 3.): Fade-in duration, if any.
fade_out (of type float, which defaults to 3.): Fade-out duration, if any.
(unlabeled) (of type source(audio=pcm('a), 'b) where 'b is a set of tracks to be muxed into a source and a set of internal tracks): Ending track
(unlabeled) (of type source(audio=pcm('a), 'b) where 'b is a set of tracks to be muxed into a source and a set of internal tracks): Starting track

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`cross.smart`

Smart transition for crossfade

Type:

(?log : ((string) -> unit), ?fade_in : float, ?fade_out : float,
 ?default : ((source(audio=pcm('a), 'b), source(audio=pcm('a), 'b)) ->
             source(audio=pcm('a), 'b)),
 ?high : float, ?medium : float, ?margin : float, 'c
 .{
   db_level : float,
   metadata : [string * string],
   source : source(audio=pcm('a),
   'b)
 }, 'd
 .{
   db_level : float,
   metadata : [string * string],
   source : source(audio=pcm('a),
   'b)
 }) -> source(audio=pcm('a), 'b)
where
  'b is a set of tracks to be muxed into a source and a set of internal tracks

Arguments:

log (of type (string) -> unit, which defaults to <fun>): Default logger
fade_in (of type float, which defaults to 3.): Fade-in duration, if any.
fade_out (of type float, which defaults to 3.): Fade-out duration, if any.
default (of type (source(audio=pcm('a), 'b), source(audio=pcm('a), 'b)) -> source(audio=pcm('a), 'b) where 'b is a set of tracks to be muxed into a source and a set of internal tracks, which defaults to <fun>): Smart crossfade: transition used when no rule applies (default: sequence).
high (of type float, which defaults to -15.): Value, in dB, for loud sound level.
medium (of type float, which defaults to -32.): Value, in dB, for medium sound level.
margin (of type float, which defaults to 4.): Margin to detect sources that have too different sound level for crossing.
(unlabeled) (of type 'c .{ db_level : float, metadata : [string * string], source : source(audio=pcm('a), 'b) } where 'b is a set of tracks to be muxed into a source and a set of internal tracks): Ending track
(unlabeled) (of type 'd .{ db_level : float, metadata : [string * string], source : source(audio=pcm('a), 'b) } where 'b is a set of tracks to be muxed into a source and a set of internal tracks): Starting track

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`crossfade`

Crossfade between tracks, taking the respective volume levels into account in the choice of the transition.

Type:

(?id : string?, ?duration : float, ?override_duration : string,
 ?persist_override : bool, ?fade_in : float, ?fade_out : float,
 ?smart : bool,
 ?default : ((source(audio=pcm('a), 'b), source(audio=pcm('a), 'b)) ->
             source(audio=pcm('a), 'b)),
 ?high : float, ?medium : float, ?margin : float, ?deduplicate : bool,
 ?minimum : float, ?width : float, ?conservative : bool,
 source(audio=pcm('a), 'b)) -> source(audio=pcm('a), 'b)
where
  'b is a set of tracks to be muxed into a source and a set of internal tracks

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
duration (of type float, which defaults to 5.): Duration (in seconds) of buffered data from each track that is used to compute the transition between tracks.
override_duration (of type string, which defaults to "liq_cross_duration"): Metadata field which, if present and containing a float, overrides the ‘duration’ parameter for current track.
persist_override (of type bool, which defaults to false): Keep duration override on track change.
fade_in (of type float, which defaults to 3.): Fade-in duration, if any.
fade_out (of type float, which defaults to 3.): Fade-out duration, if any.
smart (of type bool, which defaults to false): Enable smart crossfading
default (of type (source(audio=pcm('a), 'b), source(audio=pcm('a), 'b)) -> source(audio=pcm('a), 'b) where 'b is a set of tracks to be muxed into a source and a set of internal tracks, which defaults to <fun>): Smart crossfade: transition used when no rule applies (default: sequence).
high (of type float, which defaults to -15.): Smart crossfade: value, in dB, for loud sound level.
medium (of type float, which defaults to -32.): Smart crossfade: value, in dB, for medium sound level.
margin (of type float, which defaults to 4.): Smart crossfade: margin to detect sources that have too different sound level for crossing.
deduplicate (of type bool, which defaults to true): Crossfade transitions can generate duplicate metadata. When true, the operator removes duplicate metadata from the returned source.
minimum (of type float, which defaults to -1.): Minimum duration (in sec.) for a cross: If the track ends without any warning (e.g. in case of skip) there may not be enough data for a decent composition. Set to 0. to avoid having transitions after skips, or more to avoid transitions on short tracks. With a negative default, transitions always occur.
width (of type float, which defaults to 2.): Width of the volume analysis window.
conservative (of type bool, which defaults to true): Always prepare for a premature end-of-track.
(unlabeled) (of type source(audio=pcm('a), 'b) where 'b is a set of tracks to be muxed into a source and a set of internal tracks): The input source.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
cross_duration (of type () -> float):
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`fade.in`

Fade the beginning of tracks.

Type:

(?id : string, ?duration : float, ?override_duration : string,
 ?override_type : string, ?persist_overrides : bool, ?track_sensitive : bool,
 ?type : string, source(audio=pcm('a), 'b)) -> source(audio=pcm('a), 'b)
where 'b is a set of tracks to be muxed into a source

Arguments:

id (of type string, which defaults to "fade.in"): Force the value of the source ID.
duration (of type float, which defaults to 3.): Duration of the fading. This value can be set on a per-file basis using the metadata field passed as override.
override_duration (of type string, which defaults to "liq_fade_in"): Metadata field which, if present and containing a float, overrides the ‘duration’ parameter for the current track.
override_type (of type string, which defaults to "liq_fade_type"): Metadata field which, if present and correct, overrides the ‘type’ parameter for the current track.
persist_overrides (of type bool, which defaults to false): Keep duration and type overrides on track change.
track_sensitive (of type bool, which defaults to true): Be track sensitive (if false we only fade in once at the beginning of the track).
type (of type string, which defaults to "lin"): Fader shape (lin|sin|log|exp): linear, sinusoidal, logarithmic or exponential.
(unlabeled) (of type source(audio=pcm('a), 'b) where 'b is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fade_duration (of type () -> float):
fade_type (of type () -> string):
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`fade.out`

Fade the end of tracks.

Type:

(?id : string, ?duration : float, ?override_duration : string,
 ?override_type : string, ?persist_overrides : bool, ?track_sensitive : bool,
 ?type : string, source(audio=pcm('a), 'b)) -> source(audio=pcm('a), 'b)
where 'b is a set of tracks to be muxed into a source

Arguments:

id (of type string, which defaults to "fade.out"): Force the value of the source ID.
duration (of type float, which defaults to 3.): Duration of the fading. This value can be set on a per-file basis using the metadata field passed as override.
override_duration (of type string, which defaults to "liq_fade_out"): Metadata field which, if present and containing a float, overrides the ‘duration’ parameter for the current track.
override_type (of type string, which defaults to "liq_fade_type"): Metadata field which, if present and correct, overrides the ‘type’ parameter for the current track.
persist_overrides (of type bool, which defaults to false): Keep duration and type overrides on track change.
track_sensitive (of type bool, which defaults to true): Be track sensitive (if false we only fade ou once at the beginning of the track).
type (of type string, which defaults to "lin"): Fader shape (lin|sin|log|exp): linear, sinusoidal, logarithmic or exponential.
(unlabeled) (of type source(audio=pcm('a), 'b) where 'b is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fade_duration (of type () -> float):
fade_type (of type () -> string):
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`fade.skip`

Fade when the metadata trigger is received and then skip.

Type:

(?id : string, ?duration : float, ?override_duration : string,
 ?override_type : string, ?persist_overrides : bool, ?override_skip : string,
 ?type : string, source(audio=pcm('a), 'b)) -> source(audio=pcm('a), 'b)
where 'b is a set of tracks to be muxed into a source

Arguments:

id (of type string, which defaults to "fade.skip"): Force the value of the source ID.
duration (of type float, which defaults to 5.): Duration of the fading. This value can be set on a per-file basis using the metadata field passed as override.
override_duration (of type string, which defaults to "liq_fade_skip"): Metadata field which, if present and containing a float, overrides the ‘duration’ parameter for the current track.
override_type (of type string, which defaults to "liq_fade_type"): Metadata field which, if present and correct, overrides the ‘type’ parameter for the current track.
persist_overrides (of type bool, which defaults to false): Keep duration and type overrides on track change.
override_skip (of type string, which defaults to "liq_skip_meta"): Metadata field which, when present and set to “true”, will trigger the fade
type (of type string, which defaults to "lin"): Fader shape (lin|sin|log|exp): linear, sinusoidal, logarithmic or exponential.
(unlabeled) (of type source(audio=pcm('a), 'b) where 'b is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fade_duration (of type () -> float):
fade_type (of type () -> string):
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`mkfade`

Make a fade function based on a source’s clock.

Type:

(?type : string, ?start : float, ?stop : float, ?duration : float,
 ?on_done : (() -> unit), source('a)) -> () -> float

Arguments:

type (of type string, which defaults to "lin"): Fade shape. One of: “sin”, “exp”, “log”, “lin”
start (of type float, which defaults to 0.): Start value.
stop (of type float, which defaults to 1.): Stop value.
duration (of type float, which defaults to 3.): Duration in seconds.
on_done (of type () -> unit, which defaults to {()}): Function to execute when the fade is finished
(unlabeled) (of type source('a))

Source / Input

`blank`

Produce silence and blank images.

Type:

(?id : string?, ?duration : float) -> source('a)
where 'a is a set of internal tracks

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
duration (of type float, which defaults to -1.): Duration of blank tracks in seconds, Negative value means forever.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`input`

Input an audio stream using the default operator.

Type:

(?id : string?, ?start : bool, ?on_start : (() -> unit),
 ?on_stop : (() -> unit), ?fallible : bool) -> source(audio=pcm('A))

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
start (of type bool, which defaults to true): Automatically start outputting whenever possible. If true, an infallible (normal) output will start outputting as soon as it is created, and a fallible output will (re)start as soon as its source becomes available for streaming.
on_start (of type () -> unit, which defaults to {()}): Callback executed when outputting starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when outputting stops.
fallible (of type bool, which defaults to false): Allow the child source to fail, in which case the output will be (temporarily) stopped.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
stop (of type () -> unit): Ask the source or output to stop.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`input.alsa`

Stream from an ALSA input device.

Type:

(?id : string?, ?bufferize : bool, ?clock_safe : bool, ?device : string,
 ?fallible : bool, ?on_start : (() -> unit), ?on_stop : (() -> unit),
 ?start : bool) -> source(audio=pcm('a))

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
bufferize (of type bool, which defaults to true): Bufferize input
clock_safe (of type bool, which defaults to true): Force the use of a dedicated clock
device (of type string, which defaults to "default"): Alsa device to use
fallible (of type bool, which defaults to false): Allow the source to fail. If set to false, start must be true and stop method raises an error.
on_start (of type () -> unit, which defaults to {()}): Callback executed when input starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when input stops.
start (of type bool, which defaults to true): Start input as soon as it is available.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
stop (of type () -> unit): Ask the source or output to stop.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`input.external.avi`

Stream data from an external application.

Type:

(?id : string?, ?buffer : float, ?max : float, ?restart : bool,
 ?restart_on_error : bool, {string}) -> source(audio=pcm('a),
video=canvas('b))

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
buffer (of type float, which defaults to 1.): Duration of the pre-buffered data.
max (of type float, which defaults to 10.): Maximum duration of the buffered data.
restart (of type bool, which defaults to true): Restart process when exited.
restart_on_error (of type bool, which defaults to false): Restart process when exited with error.
(unlabeled) (of type {string}): Command to execute.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

This function is experimental.

`input.external.rawaudio`

Stream raw PCM data (interleaved signed 16 bits little endian integers) from an external application.

Type:

(?id : string?, ?buffer : float, ?channels : int, ?max : float,
 ?restart : bool, ?restart_on_error : bool, ?samplerate : int, {string}) ->
source(audio=pcm('a))

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
buffer (of type float, which defaults to 2.): Duration of the pre-buffered data.
channels (of type int, which defaults to 2): Number of channels.
max (of type float, which defaults to 10.): Maximum duration of the buffered data.
restart (of type bool, which defaults to true): Restart process when exited.
restart_on_error (of type bool, which defaults to false): Restart process when exited with error.
samplerate (of type int, which defaults to 44100): Samplerate.
(unlabeled) (of type {string}): Command to execute.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`input.external.rawvideo`

Stream data from an external application.

Type:

(?id : string?, ?buffer : float, ?max : float, ?restart : bool,
 ?restart_on_error : bool, {string}) -> source(video=canvas('a))

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
buffer (of type float, which defaults to 1.): Duration of the pre-buffered data.
max (of type float, which defaults to 10.): Maximum duration of the buffered data.
restart (of type bool, which defaults to true): Restart process when exited.
restart_on_error (of type bool, which defaults to false): Restart process when exited with error.
(unlabeled) (of type {string}): Command to execute.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

This function is experimental.

`input.external.wav`

Stream WAV data from an external application.

Type:

(?id : string?, ?buffer : float, ?max : float, ?restart : bool,
 ?restart_on_error : bool, {string}) -> source(audio=pcm('a))

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
buffer (of type float, which defaults to 2.): Duration of the pre-buffered data.
max (of type float, which defaults to 10.): Maximum duration of the buffered data.
restart (of type bool, which defaults to true): Restart process when exited.
restart_on_error (of type bool, which defaults to false): Restart process when exited with error.
(unlabeled) (of type {string}): Command to execute.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`input.ffmpeg`

Create a stream using ffmpeg

Type:

(?id : string?, ?clock_safe : bool, ?debug : bool,
 ?deduplicate_metadata : bool, ?float_args : [string * float],
 ?format : string?, ?int_args : [string * int], ?max_buffer : float,
 ?metadata_filter : (([string * string]) -> [string * string])?,
 ?new_track_on_metadata : bool, ?on_connect : (() -> unit),
 ?on_disconnect : (() -> unit),
 ?on_error : ((error
               .{
                 kind : string,
                 message : string,
                 trace : [
                          {
                            position_end : 
                            {
                              character_offset : int,
                              filename : string,
                              line_number : int
                            },
                            position_start : 
                            {
                              character_offset : int,
                              filename : string,
                              line_number : int
                            },
                            to_string : (?prefix : string) -> string
                          }]
               }) -> unit),
 ?on_start : (() -> unit), ?on_stop : (() -> unit), ?poll_delay : float,
 ?self_sync : {bool}, ?start : bool, ?string_args : [string * string],
 {string}) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
clock_safe (of type bool, which defaults to false): Force the use of a dedicated clock
debug (of type bool, which defaults to false): Run in debugging mode, not catching some exceptions.
deduplicate_metadata (of type bool, which defaults to true): Prevent duplicated metadata.
float_args (of type [string * float], which defaults to [])
format (of type string?, which defaults to null): Force a specific input format. Autodetected when passed a null argument
int_args (of type [string * int], which defaults to [])
max_buffer (of type float, which defaults to 5.): Maximum uration of buffered data
metadata_filter (of type (([string * string]) -> [string * string])?, which defaults to null): Metadata filter function. Returned metadata are set a metadata. Default: filter id3v2_priv metadata.
new_track_on_metadata (of type bool, which defaults to true): Treat new metadata as new track.
on_connect (of type () -> unit, which defaults to {()}): Function to execute when a source is connected.
on_disconnect (of type () -> unit, which defaults to {()}): Function to execute when a source is disconnected
on_error (of type (error .{ kind : string, message : string, trace : [ { position_end : {character_offset : int, filename : string, line_number : int }, position_start : {character_offset : int, filename : string, line_number : int }, to_string : (?prefix : string) -> string }] }) -> unit, which defaults to fun (_) -> ()): Callback executed when an error occurs.
on_start (of type () -> unit, which defaults to {()}): Callback executed when input starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when input stops.
poll_delay (of type float, which defaults to 2.): Polling delay when trying to connect to the stream.
self_sync (of type {bool}, which defaults to false): Should the source control its own timing? Set to true if you are having synchronization issues. Should be false for most typical cases.
start (of type bool, which defaults to true): Start input as soon as it is available.
string_args (of type [string * string], which defaults to [])
(unlabeled) (of type {string}): URL to decode.

Methods:

buffer_length (of type () -> float): Get the buffer’s length in seconds.
buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
set_url (of type ({string}) -> unit): Set the source’s url.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
status (of type () -> string): Return the current status of the source, either “stopped” (the source isn’t trying to relay the HTTP stream), “starting” (polling task is about to begin) “polling” (attempting to connect to the HTTP stream), “connected ” (connected to , buffering or playing back the stream) or “stopping” (source is stopping).
stop (of type () -> unit): Ask the source or output to stop.
time (of type () -> float): Get a source’s time, based on its assigned clock.
url (of type () -> string): Return the source’s current url.

`input.harbor`

Create a source that receives a http/icecast stream and forwards it as a stream.

Type:

(?id : string?,
 ?auth : (({address : string, password : string, user : string}) -> bool)?,
 ?buffer : float, ?debug : bool, ?dumpfile : string?, ?icy : bool,
 ?icy_metadata_charset : string?, ?logfile : string?, ?max : float,
 ?metadata_charset : string?, ?on_connect : (([string * string]) -> unit),
 ?on_disconnect : (() -> unit), ?password : string, ?port : int,
 ?replay_metadata : bool, ?timeout : float, ?transport : http_transport,
 ?user : string, string) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
auth (of type (({address : string, password : string, user : string}) -> bool)?, which defaults to null): Authentication function. Receives a record with: user, password and address (client network address) and returns true if the user should be granted access for this login. Override any other method if used.
buffer (of type float, which defaults to 12.): Duration of the pre-buffered data (in seconds). Default value is set to make it possible to use crossfade transitions with input.harbor. You might be able to reduce it but, in this case, make sure to not use the operator with crossfade or make sure that it has enough buffered data for it.
debug (of type bool, which defaults to false): Run in debugging mode by not catching some exceptions.
dumpfile (of type string?, which defaults to null): Dump stream to file, for debugging purpose. Disabled if null.
icy (of type bool, which defaults to false): Enable ICY (shoutcast) protocol.
icy_metadata_charset (of type string?, which defaults to null): ICY (shoutcast) metadata charset. Guessed if null. Default for shoutcast is ISO-8859-1. Set to that value if all your clients send metadata using this charset and automatic detection is not working for you.
logfile (of type string?, which defaults to null): Log buffer status to file, for debugging purpose. Disabled if null.
max (of type float, which defaults to 20.): Maximum duration of the buffered data (in seconds).
metadata_charset (of type string?, which defaults to null): Metadata charset for non-ICY (shoutcast) source protocols. Guessed if null.
on_connect (of type ([string * string]) -> unit, which defaults to fun (_) -> ()): Function to execute when a source is connected. Its receives the list of headers, of the form: (,). All labels are lowercase.
on_disconnect (of type () -> unit, which defaults to {()}): Functions to execute when a source is disconnected
password (of type string, which defaults to "hackme"): Source password.
port (of type int, which defaults to 8005): Port used to connect to the source.
replay_metadata (of type bool, which defaults to false): Replay last known metadata when switching back to this source. This helps when source has dropped due to temporary connection issues.
timeout (of type float, which defaults to 30.): Timeout for source connectionn.
transport (of type http_transport, which defaults to <unix_transport>): Http transport. Use http.transport.ssl or http.transport.secure_transport, when available, to enable HTTPS output
user (of type string, which defaults to "source"): Source user.
(unlabeled) (of type string): Mountpoint to look for.

Methods:

buffer_length (of type () -> float): Length of the buffer (in seconds).
buffered (of type () -> [string * float]): Length of buffered data.
connected_client (of type () -> string?): Returns the address of the client currently connected, if there is one.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
status (of type () -> string): Current status of the input.
stop (of type () -> unit): Disconnect the client currently connected to the harbor. Does nothing if no client is connected.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`input.hls`

Play an HLS stream.

Type:

(?id : string?, {string}) -> source('A)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
(unlabeled) (of type {string}): Playlist URI.

Methods:

buffer_length (of type () -> float): Get the buffer’s length in seconds.
buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
set_url (of type ({string}) -> unit): Set the source’s url.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
status (of type () -> string): Return the current status of the source, either “stopped” (the source isn’t trying to relay the HTTP stream), “starting” (polling task is about to begin) “polling” (attempting to connect to the HTTP stream), “connected ” (connected to , buffering or playing back the stream) or “stopping” (source is stopping).
stop (of type () -> unit): Ask the source or output to stop.
time (of type () -> float): Get a source’s time, based on its assigned clock.
url (of type () -> string): Return the source’s current url.

`input.hls.native`

Play an HLS stream.

Type:

(?id : string?, ?reload : float, string) -> source('a)
where 'a is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
reload (of type float, which defaults to 10.): How often (in seconds) the playlist should be reloaded.
(unlabeled) (of type string): Playlist URI.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

This function is experimental.

`input.http`

Create a http stream using ffmpeg

Type:

(?id : string?, ?clock_safe : bool, ?debug : bool,
 ?deduplicate_metadata : bool, ?float_args : [string * float],
 ?format : string?, ?int_args : [string * int], ?max_buffer : float,
 ?metadata_filter : (([string * string]) -> [string * string])?,
 ?new_track_on_metadata : bool, ?on_connect : (([string * string]) -> unit),
 ?on_disconnect : (() -> unit),
 ?on_error : ((error
               .{
                 kind : string,
                 message : string,
                 trace : [
                          {
                            position_end : 
                            {
                              character_offset : int,
                              filename : string,
                              line_number : int
                            },
                            position_start : 
                            {
                              character_offset : int,
                              filename : string,
                              line_number : int
                            },
                            to_string : (?prefix : string) -> string
                          }]
               }) -> unit),
 ?on_start : (() -> unit), ?on_stop : (() -> unit), ?poll_delay : float,
 ?self_sync : {bool?}, ?start : bool, ?string_args : [string * string],
 ?timeout : float, ?user_agent : string, {string}) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
clock_safe (of type bool, which defaults to false): Force the use of a dedicated clock
debug (of type bool, which defaults to false): Run in debugging mode, not catching some exceptions.
deduplicate_metadata (of type bool, which defaults to true): Prevent duplicated metadata.
float_args (of type [string * float], which defaults to [])
format (of type string?, which defaults to null): Force a specific input format. Autodetected when passed a null argument
int_args (of type [string * int], which defaults to [])
max_buffer (of type float, which defaults to 5.): Maximum uration of buffered data
metadata_filter (of type (([string * string]) -> [string * string])?, which defaults to null): Metadata filter function. Returned metadata are set a metadata. Default: filter id3v2_priv metadata.
new_track_on_metadata (of type bool, which defaults to true): Treat new metadata as new track.
on_connect (of type ([string * string]) -> unit, which defaults to fun (_) -> ()): Function to execute when a source is connected. Its receives the list of ICY-specific headers, if available.
on_disconnect (of type () -> unit, which defaults to {()}): Function to execute when a source is disconnected
on_error (of type (error .{ kind : string, message : string, trace : [ { position_end : {character_offset : int, filename : string, line_number : int }, position_start : {character_offset : int, filename : string, line_number : int }, to_string : (?prefix : string) -> string }] }) -> unit, which defaults to fun (_) -> ()): Callback executed when an error occurs.
on_start (of type () -> unit, which defaults to {()}): Callback executed when input starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when input stops.
poll_delay (of type float, which defaults to 2.): Polling delay when trying to connect to the stream.
self_sync (of type {bool?}, which defaults to null): Should the source control its own timing? If null, the source will control its latency if it can be detected that it is connecting to an icecast or shoutcast server. Otherwise, see input.ffmpeg for more details about this option.
start (of type bool, which defaults to true): Start input as soon as it is available.
string_args (of type [string * string], which defaults to [])
timeout (of type float, which defaults to 10.): Timeout for source connection.
user_agent (of type string, which defaults to "Liquidsoap/2.2.0 (Unix; OCaml 4.14.1)"): User agent.
(unlabeled) (of type {string}): URL to decode.

Methods:

buffer_length (of type () -> float): Get the buffer’s length in seconds.
buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
set_url (of type ({string}) -> unit): Set the source’s url.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
status (of type () -> string): Return the current status of the source, either “stopped” (the source isn’t trying to relay the HTTP stream), “starting” (polling task is about to begin) “polling” (attempting to connect to the HTTP stream), “connected ” (connected to , buffering or playing back the stream) or “stopping” (source is stopping).
stop (of type () -> unit): Ask the source or output to stop.
time (of type () -> float): Get a source’s time, based on its assigned clock.
url (of type () -> string): Return the source’s current url.

`input.jack`

Get stream from jack.

Type:

(?id : string?, ?buffer_size : int, ?clock_safe : bool, ?fallible : bool,
 ?on_start : (() -> unit), ?on_stop : (() -> unit), ?server : string,
 ?start : bool) -> source(audio=pcm('a))

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
buffer_size (of type int, which defaults to 2): Set buffer size, in frames. Must be >= 1.
clock_safe (of type bool, which defaults to true): Force the use of a dedicated clock
fallible (of type bool, which defaults to false): Allow the source to fail. If set to false, start must be true and stop method raises an error.
on_start (of type () -> unit, which defaults to {()}): Callback executed when input starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when input stops.
server (of type string, which defaults to ""): Jack server to connect to.
start (of type bool, which defaults to true): Start input as soon as it is available.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
stop (of type () -> unit): Ask the source or output to stop.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`input.keyboard.sdl`

Play notes from the keyboard.

Type:

(?id : string?, ?velocity : float) -> source(midi=midi('a))

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
velocity (of type float, which defaults to 0.8): Velocity of notes.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

This function is experimental.

`input.oss`

Stream from an OSS input device.

Type:

(?id : string?, ?clock_safe : bool, ?device : string, ?fallible : bool,
 ?on_start : (() -> unit), ?on_stop : (() -> unit), ?start : bool) ->
source(audio=pcm('a))

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
clock_safe (of type bool, which defaults to true): Force the use of a dedicated clock
device (of type string, which defaults to "/dev/dsp"): OSS device to use.
fallible (of type bool, which defaults to false): Allow the source to fail. If set to false, start must be true and stop method raises an error.
on_start (of type () -> unit, which defaults to {()}): Callback executed when input starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when input stops.
start (of type bool, which defaults to true): Start input as soon as it is available.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
stop (of type () -> unit): Ask the source or output to stop.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`input.portaudio`

Stream from a portaudio input device.

Type:

(?id : string?, ?buflen : int, ?clock_safe : bool, ?device_id : int?,
 ?fallible : bool, ?latency : float?, ?on_start : (() -> unit),
 ?on_stop : (() -> unit), ?start : bool) -> source(audio=pcm('a))

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
buflen (of type int, which defaults to 256): Length of a buffer in samples.
clock_safe (of type bool, which defaults to true): Force the use of a dedicated clock
device_id (of type int?, which defaults to null): Device ID. Uses default device if null.
fallible (of type bool, which defaults to false): Allow the source to fail. If set to false, start must be true and stop method raises an error.
latency (of type float?, which defaults to null): Device latency. Only used when specifying device ID.
on_start (of type () -> unit, which defaults to {()}): Callback executed when input starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when input stops.
start (of type bool, which defaults to true): Start input as soon as it is available.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
stop (of type () -> unit): Ask the source or output to stop.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`input.pulseaudio`

Stream from a pulseaudio input device.

Type:

(?id : string?, ?client : string, ?clock_safe : bool, ?clock_safe : bool,
 ?device : string, ?fallible : bool, ?on_start : (() -> unit),
 ?on_stop : (() -> unit), ?start : bool) -> source(audio=pcm('a))

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
client (of type string, which defaults to "liquidsoap")
clock_safe (of type bool, which defaults to true): Force the use of a dedicated clock
clock_safe (of type bool, which defaults to true): Force the use of the dedicated Pulseaudio clock.
device (of type string, which defaults to ""): Device to use. Uses default if set to ““.
fallible (of type bool, which defaults to false): Allow the source to fail. If set to false, start must be true and stop method raises an error.
on_start (of type () -> unit, which defaults to {()}): Callback executed when input starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when input stops.
start (of type bool, which defaults to true): Start input as soon as it is available.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
stop (of type () -> unit): Ask the source or output to stop.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`input.rtmp`

Read an RTMP stream.

Type:

(?id : string?, ?max_buffer : float, ?listen : bool, {string}) -> source('a)

Arguments:

id (of type string?, which defaults to null)
max_buffer (of type float, which defaults to 5.): Maximum data buffer in seconds
listen (of type bool, which defaults to true): Act as a RTMP server and wait for incoming connection
(unlabeled) (of type {string}): URL to read RTMP from, in the form rtmp://IP:PORT/ENDPOINT

Methods:

buffer_length (of type () -> float): Get the buffer’s length in seconds.
buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
set_url (of type ({string}) -> unit): Set the source’s url.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
status (of type () -> string): Return the current status of the source, either “stopped” (the source isn’t trying to relay the HTTP stream), “starting” (polling task is about to begin) “polling” (attempting to connect to the HTTP stream), “connected ” (connected to , buffering or playing back the stream) or “stopping” (source is stopping).
stop (of type () -> unit): Ask the source or output to stop.
time (of type () -> float): Get a source’s time, based on its assigned clock.
url (of type () -> string): Return the source’s current url.

`input.srt`

Receive a SRT stream from a distant agent.

Type:

(?id : string?, ?bind_address : string, ?clock_safe : bool,
 ?connection_timeout : float?, ?content_type : string, ?dump : string,
 ?enforced_encryption : bool?, ?host : string,
 ?listen_callback : ((hs_version : int, peeraddr : string,
                      streamid : string?, srt_socket
                      .{
                        bistats : (?clear : bool?, ?instantaneous : bool?) -> 
                                  {
                                    byteAvailRcvBuf : int,
                                    byteAvailSndBuf : int,
                                    byteMSS : int,
                                    byteRcvBuf : int,
                                    byteRcvDrop : int,
                                    byteRcvDropTotal : int,
                                    byteRcvUndecrypt : int,
                                    byteRcvUndecryptTotal : int,
                                    byteRecv : int,
                                    byteRecvTotal : int,
                                    byteRetrans : int,
                                    byteRetransTotal : int,
                                    byteSent : int,
                                    byteSentTotal : int,
                                    byteSndBuf : int,
                                    byteSndDrop : int,
                                    byteSndDropTotal : int,
                                    mbpsBandwidth : float,
                                    mbpsMaxBW : float,
                                    mbpsRecvRate : float,
                                    mbpsSendRate : float,
                                    msRTT : float,
                                    msRcvBuf : int,
                                    msRcvTsbPdDelay : int,
                                    msSndBuf : int,
                                    msSndTsbPdDelay : int,
                                    msTimeStamp : int,
                                    pktCongestionWindow : int,
                                    pktFlightSize : int,
                                    pktFlowWindow : int,
                                    pktRcvAvgBelatedTime : float,
                                    pktRcvBelated : int,
                                    pktRcvBuf : int,
                                    pktRcvDrop : int,
                                    pktRcvDropTotal : int,
                                    pktRcvFilterExtra : int,
                                    pktRcvFilterExtraTotal : int,
                                    pktRcvFilterLoss : int,
                                    pktRcvFilterLossTotal : int,
                                    pktRcvFilterSupply : int,
                                    pktRcvFilterSupplyTotal : int,
                                    pktRcvLoss : int,
                                    pktRcvLossTotal : int,
                                    pktRcvRetrans : int,
                                    pktRcvUndecrypt : int,
                                    pktRcvUndecryptTotal : int,
                                    pktRecv : int,
                                    pktRecvACK : int,
                                    pktRecvACKTotal : int,
                                    pktRecvNAK : int,
                                    pktRecvNAKTotal : int,
                                    pktRecvTotal : int,
                                    pktReorderDistance : int,
                                    pktRetrans : int,
                                    pktRetransTotal : int,
                                    pktSent : int,
                                    pktSentACK : int,
                                    pktSentACKTotal : int,
                                    pktSentNAK : int,
                                    pktSentNAKTotal : int,
                                    pktSentTotal : int,
                                    pktSndBuf : int,
                                    pktSndDrop : int,
                                    pktSndDropTotal : int,
                                    pktSndFilterExtra : int,
                                    pktSndFilterExtraTotal : int,
                                    pktSndLoss : int,
                                    pktSndLossTotal : int,
                                    usPktSndPeriod : float,
                                    usSndDuration : int,
                                    usSndDurationTotal : int},
                        bstats : (?clear : bool?) -> 
                                 {
                                   byteAvailRcvBuf : int,
                                   byteAvailSndBuf : int,
                                   byteMSS : int,
                                   byteRcvBuf : int,
                                   byteRcvDrop : int,
                                   byteRcvDropTotal : int,
                                   byteRcvUndecrypt : int,
                                   byteRcvUndecryptTotal : int,
                                   byteRecv : int,
                                   byteRecvTotal : int,
                                   byteRetrans : int,
                                   byteRetransTotal : int,
                                   byteSent : int,
                                   byteSentTotal : int,
                                   byteSndBuf : int,
                                   byteSndDrop : int,
                                   byteSndDropTotal : int,
                                   mbpsBandwidth : float,
                                   mbpsMaxBW : float,
                                   mbpsRecvRate : float,
                                   mbpsSendRate : float,
                                   msRTT : float,
                                   msRcvBuf : int,
                                   msRcvTsbPdDelay : int,
                                   msSndBuf : int,
                                   msSndTsbPdDelay : int,
                                   msTimeStamp : int,
                                   pktCongestionWindow : int,
                                   pktFlightSize : int,
                                   pktFlowWindow : int,
                                   pktRcvAvgBelatedTime : float,
                                   pktRcvBelated : int,
                                   pktRcvBuf : int,
                                   pktRcvDrop : int,
                                   pktRcvDropTotal : int,
                                   pktRcvFilterExtra : int,
                                   pktRcvFilterExtraTotal : int,
                                   pktRcvFilterLoss : int,
                                   pktRcvFilterLossTotal : int,
                                   pktRcvFilterSupply : int,
                                   pktRcvFilterSupplyTotal : int,
                                   pktRcvLoss : int,
                                   pktRcvLossTotal : int,
                                   pktRcvRetrans : int,
                                   pktRcvUndecrypt : int,
                                   pktRcvUndecryptTotal : int,
                                   pktRecv : int,
                                   pktRecvACK : int,
                                   pktRecvACKTotal : int,
                                   pktRecvNAK : int,
                                   pktRecvNAKTotal : int,
                                   pktRecvTotal : int,
                                   pktReorderDistance : int,
                                   pktRetrans : int,
                                   pktRetransTotal : int,
                                   pktSent : int,
                                   pktSentACK : int,
                                   pktSentACKTotal : int,
                                   pktSentNAK : int,
                                   pktSentNAKTotal : int,
                                   pktSentTotal : int,
                                   pktSndBuf : int,
                                   pktSndDrop : int,
                                   pktSndDropTotal : int,
                                   pktSndFilterExtra : int,
                                   pktSndFilterExtraTotal : int,
                                   pktSndLoss : int,
                                   pktSndLossTotal : int,
                                   usPktSndPeriod : float,
                                   usSndDuration : int,
                                   usSndDurationTotal : int},
                        close : () -> unit,
                        pbkeylen : () -> int,
                        read_data : () -> int,
                        read_latency : () -> int,
                        read_timeout : () -> int,
                        status : () -> string,
                        streamid : () -> string,
                        write_timeout : () -> int
                      }) -> bool)?,
 ?max : float, ?messageapi : bool, ?mode : string,
 ?on_connect : (() -> unit), ?on_disconnect : (() -> unit),
 ?on_start : (() -> unit), ?on_stop : (() -> unit), ?passphrase : string?,
 ?payload_size : int, ?pbkeylen : int?, ?polling_delay : float, ?port : int,
 ?read_timeout : float?, ?start : bool, ?streamid : string?,
 ?write_timeout : float?) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
bind_address (of type string, which defaults to "0.0.0.0"): Address to bind on the local machine. Used only in listener mode
clock_safe (of type bool, which defaults to true): Force the use of a dedicated clock
connection_timeout (of type float?, which defaults to null): Timeout, in seconds, after which initial connection operations are aborted if no data was received. Uses library’s default if nulll. Used only in client mode.
content_type (of type string, which defaults to "application/ffmpeg"): Content-Type (mime type) used to find a decoder for the input stream.
dump (of type string, which defaults to ""): Dump received data to the given file for debugging. Unused is empty.
enforced_encryption (of type bool?, which defaults to null): Enforces that both connection parties have the same passphrase set, or both do not set the passphrase, otherwise the connection is rejected.
host (of type string, which defaults to "localhost"): Address to connect to. Used only in caller mode.
listen_callback (of type ((hs_version : int, peeraddr : string, streamid : string?, srt_socket .{ bistats : (?clear : bool?, ?instantaneous : bool?) -> { byteAvailRcvBuf : int, byteAvailSndBuf : int, byteMSS : int, byteRcvBuf : int, byteRcvDrop : int, byteRcvDropTotal : int, byteRcvUndecrypt : int, byteRcvUndecryptTotal : int, byteRecv : int, byteRecvTotal : int, byteRetrans : int, byteRetransTotal : int, byteSent : int, byteSentTotal : int, byteSndBuf : int, byteSndDrop : int, byteSndDropTotal : int, mbpsBandwidth : float, mbpsMaxBW : float, mbpsRecvRate : float, mbpsSendRate : float, msRTT : float, msRcvBuf : int, msRcvTsbPdDelay : int, msSndBuf : int, msSndTsbPdDelay : int, msTimeStamp : int, pktCongestionWindow : int, pktFlightSize : int, pktFlowWindow : int, pktRcvAvgBelatedTime : float, pktRcvBelated : int, pktRcvBuf : int, pktRcvDrop : int, pktRcvDropTotal : int, pktRcvFilterExtra : int, pktRcvFilterExtraTotal : int, pktRcvFilterLoss : int, pktRcvFilterLossTotal : int, pktRcvFilterSupply : int, pktRcvFilterSupplyTotal : int, pktRcvLoss : int, pktRcvLossTotal : int, pktRcvRetrans : int, pktRcvUndecrypt : int, pktRcvUndecryptTotal : int, pktRecv : int, pktRecvACK : int, pktRecvACKTotal : int, pktRecvNAK : int, pktRecvNAKTotal : int, pktRecvTotal : int, pktReorderDistance : int, pktRetrans : int, pktRetransTotal : int, pktSent : int, pktSentACK : int, pktSentACKTotal : int, pktSentNAK : int, pktSentNAKTotal : int, pktSentTotal : int, pktSndBuf : int, pktSndDrop : int, pktSndDropTotal : int, pktSndFilterExtra : int, pktSndFilterExtraTotal : int, pktSndLoss : int, pktSndLossTotal : int, usPktSndPeriod : float, usSndDuration : int, usSndDurationTotal : int}, bstats : (?clear : bool?) -> { byteAvailRcvBuf : int, byteAvailSndBuf : int, byteMSS : int, byteRcvBuf : int, byteRcvDrop : int, byteRcvDropTotal : int, byteRcvUndecrypt : int, byteRcvUndecryptTotal : int, byteRecv : int, byteRecvTotal : int, byteRetrans : int, byteRetransTotal : int, byteSent : int, byteSentTotal : int, byteSndBuf : int, byteSndDrop : int, byteSndDropTotal : int, mbpsBandwidth : float, mbpsMaxBW : float, mbpsRecvRate : float, mbpsSendRate : float, msRTT : float, msRcvBuf : int, msRcvTsbPdDelay : int, msSndBuf : int, msSndTsbPdDelay : int, msTimeStamp : int, pktCongestionWindow : int, pktFlightSize : int, pktFlowWindow : int, pktRcvAvgBelatedTime : float, pktRcvBelated : int, pktRcvBuf : int, pktRcvDrop : int, pktRcvDropTotal : int, pktRcvFilterExtra : int, pktRcvFilterExtraTotal : int, pktRcvFilterLoss : int, pktRcvFilterLossTotal : int, pktRcvFilterSupply : int, pktRcvFilterSupplyTotal : int, pktRcvLoss : int, pktRcvLossTotal : int, pktRcvRetrans : int, pktRcvUndecrypt : int, pktRcvUndecryptTotal : int, pktRecv : int, pktRecvACK : int, pktRecvACKTotal : int, pktRecvNAK : int, pktRecvNAKTotal : int, pktRecvTotal : int, pktReorderDistance : int, pktRetrans : int, pktRetransTotal : int, pktSent : int, pktSentACK : int, pktSentACKTotal : int, pktSentNAK : int, pktSentNAKTotal : int, pktSentTotal : int, pktSndBuf : int, pktSndDrop : int, pktSndDropTotal : int, pktSndFilterExtra : int, pktSndFilterExtraTotal : int, pktSndLoss : int, pktSndLossTotal : int, usPktSndPeriod : float, usSndDuration : int, usSndDurationTotal : int}, close : () -> unit, pbkeylen : () -> int, read_data : () -> int, read_latency : () -> int, read_timeout : () -> int, status : () -> string, streamid : () -> string, write_timeout : () -> int }) -> bool)?, which defaults to null): Callback used to decide whether to accept new incoming connections. Used in listener mode only.
max (of type float, which defaults to 10.): Maximum duration of the buffered data.
messageapi (of type bool, which defaults to true): Use message api
mode (of type string, which defaults to "listener"): Mode to operate on. One of: "listener" (waits for connection to come in) or "caller" (initiate connection to a remote server)
on_connect (of type () -> unit, which defaults to {()}): Function to execute when connected.
on_disconnect (of type () -> unit, which defaults to {()}): Function to execute when disconnected
on_start (of type () -> unit, which defaults to {()}): Callback executed when input starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when input stops.
passphrase (of type string?, which defaults to null): When set to a non-empty string, this option enables encryption and sets the passphrase for it. See libsrt documentation for more details.
payload_size (of type int, which defaults to 1316): Payload size.
pbkeylen (of type int?, which defaults to null): Set encryption key length. See libsrt documentation for more details.
polling_delay (of type float, which defaults to 2.): Delay between connection attempts. Used only in caller mode.
port (of type int, which defaults to 8000): Port to bind on the local machine (listener mode) or to connect to (caller mode). The term port as used in SRT is occasionally identical to the term UDP port. However SRT offers more flexibility than UDP because it manages ports as its own resources. For example, one port may be shared between various services.
read_timeout (of type float?, which defaults to 1.): Timeout, in seconds, after which read operations are aborted if no data was received, indefinite if null.
start (of type bool, which defaults to true): Start input as soon as it is available.
streamid (of type string?, which defaults to null): Set streamid. This value can be retrieved by the listener side when connecting to it. Used in caller mode only.
write_timeout (of type float?, which defaults to 1.): Timeout, in seconds, after which write operations are aborted if no data was received, indefinite if null.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
sockets (of type () -> [string * srt_socket .{ bistats : (?clear : bool?, ?instantaneous : bool?) -> { byteAvailRcvBuf : int, byteAvailSndBuf : int, byteMSS : int, byteRcvBuf : int, byteRcvDrop : int, byteRcvDropTotal : int, byteRcvUndecrypt : int, byteRcvUndecryptTotal : int, byteRecv : int, byteRecvTotal : int, byteRetrans : int, byteRetransTotal : int, byteSent : int, byteSentTotal : int, byteSndBuf : int, byteSndDrop : int, byteSndDropTotal : int, mbpsBandwidth : float, mbpsMaxBW : float, mbpsRecvRate : float, mbpsSendRate : float, msRTT : float, msRcvBuf : int, msRcvTsbPdDelay : int, msSndBuf : int, msSndTsbPdDelay : int, msTimeStamp : int, pktCongestionWindow : int, pktFlightSize : int, pktFlowWindow : int, pktRcvAvgBelatedTime : float, pktRcvBelated : int, pktRcvBuf : int, pktRcvDrop : int, pktRcvDropTotal : int, pktRcvFilterExtra : int, pktRcvFilterExtraTotal : int, pktRcvFilterLoss : int, pktRcvFilterLossTotal : int, pktRcvFilterSupply : int, pktRcvFilterSupplyTotal : int, pktRcvLoss : int, pktRcvLossTotal : int, pktRcvRetrans : int, pktRcvUndecrypt : int, pktRcvUndecryptTotal : int, pktRecv : int, pktRecvACK : int, pktRecvACKTotal : int, pktRecvNAK : int, pktRecvNAKTotal : int, pktRecvTotal : int, pktReorderDistance : int, pktRetrans : int, pktRetransTotal : int, pktSent : int, pktSentACK : int, pktSentACKTotal : int, pktSentNAK : int, pktSentNAKTotal : int, pktSentTotal : int, pktSndBuf : int, pktSndDrop : int, pktSndDropTotal : int, pktSndFilterExtra : int, pktSndFilterExtraTotal : int, pktSndLoss : int, pktSndLossTotal : int, usPktSndPeriod : float, usSndDuration : int, usSndDurationTotal : int}, bstats : (?clear : bool?) -> { byteAvailRcvBuf : int, byteAvailSndBuf : int, byteMSS : int, byteRcvBuf : int, byteRcvDrop : int, byteRcvDropTotal : int, byteRcvUndecrypt : int, byteRcvUndecryptTotal : int, byteRecv : int, byteRecvTotal : int, byteRetrans : int, byteRetransTotal : int, byteSent : int, byteSentTotal : int, byteSndBuf : int, byteSndDrop : int, byteSndDropTotal : int, mbpsBandwidth : float, mbpsMaxBW : float, mbpsRecvRate : float, mbpsSendRate : float, msRTT : float, msRcvBuf : int, msRcvTsbPdDelay : int, msSndBuf : int, msSndTsbPdDelay : int, msTimeStamp : int, pktCongestionWindow : int, pktFlightSize : int, pktFlowWindow : int, pktRcvAvgBelatedTime : float, pktRcvBelated : int, pktRcvBuf : int, pktRcvDrop : int, pktRcvDropTotal : int, pktRcvFilterExtra : int, pktRcvFilterExtraTotal : int, pktRcvFilterLoss : int, pktRcvFilterLossTotal : int, pktRcvFilterSupply : int, pktRcvFilterSupplyTotal : int, pktRcvLoss : int, pktRcvLossTotal : int, pktRcvRetrans : int, pktRcvUndecrypt : int, pktRcvUndecryptTotal : int, pktRecv : int, pktRecvACK : int, pktRecvACKTotal : int, pktRecvNAK : int, pktRecvNAKTotal : int, pktRecvTotal : int, pktReorderDistance : int, pktRetrans : int, pktRetransTotal : int, pktSent : int, pktSentACK : int, pktSentACKTotal : int, pktSentNAK : int, pktSentNAKTotal : int, pktSentTotal : int, pktSndBuf : int, pktSndDrop : int, pktSndDropTotal : int, pktSndFilterExtra : int, pktSndFilterExtraTotal : int, pktSndLoss : int, pktSndLossTotal : int, usPktSndPeriod : float, usSndDuration : int, usSndDurationTotal : int}, close : () -> unit, pbkeylen : () -> int, read_data : () -> int, read_latency : () -> int, read_timeout : () -> int, status : () -> string, streamid : () -> string, write_timeout : () -> int }]): List of (connected_address, connected_socket)
start (of type () -> unit): Ask the source or output to start.
stop (of type () -> unit): Ask the source or output to stop.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`input.v4l2`

Stream from a video4linux2 input device, such as a webcam.

Type:

(?id : string?, ?max_buffer : float, ?device : string) ->
source(video=canvas('a))

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
max_buffer (of type float, which defaults to 0.5): Maximum data buffer in seconds
device (of type string, which defaults to "/dev/video0"): V4L2 device to use.

`native.request.dynamic`

Play request dynamically created by a given function.

Type:

(?id : string?, ?available : {bool}, ?prefetch : int, ?retry_delay : {float},
 ?timeout : float, (() -> request?)) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
available (of type {bool}, which defaults to true): Whether some new requests are available (when set to false, it stops after current playing request).
prefetch (of type int, which defaults to 1): How many requests should be queued in advance.
retry_delay (of type {float}, which defaults to 0.1): Retry after a given time (in seconds) when callback returns null.
timeout (of type float, which defaults to 20.): Timeout (in sec.) for a single download.
(unlabeled) (of type () -> request?)

Methods:

add (of type (request) -> bool):
buffered (of type () -> [string * float]): Length of buffered data.
current (of type () -> request?):
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
fetch (of type () -> bool):
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
queue (of type () -> [request]):
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
set (of type (source('A)) -> unit): Set the source.
set_queue (of type ([request]) -> unit):
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`noise`

Generate audio/video noise source.

Type:

(?id : string?, ?duration : float?) -> source('a)
where 'a is a set of internal tracks

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
duration (of type float?, which defaults to null): Duration in seconds (null means infinite).

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`playlist`

Read a playlist or a directory and play all files.

Type:

(?id : string?, ?check_next : ((request) -> bool)?, ?prefetch : int,
 ?loop : bool, ?mime_type : string?, ?mode : string, ?native : bool,
 ?on_reload : ((string) -> unit), ?prefix : string, ?reload : int,
 ?reload_mode : string, ?timeout : float, string) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
check_next (of type ((request) -> bool)?, which defaults to null): Function used to filter next tracks. A candidate track is only validated if the function returns true on it. The function is called before resolution, hence metadata will only be available for requests corresponding to local files. This is typically used to avoid repetitions, but be careful: if the function rejects all attempts, the playlist will enter into a consuming loop and stop playing anything.
prefetch (of type int, which defaults to 1): How many requests should be queued in advance.
loop (of type bool, which defaults to true): Loop on the playlist.
mime_type (of type string?, which defaults to null): Default MIME type for the playlist. null means automatic detection.
mode (of type string, which defaults to "randomize"): Play the files in the playlist either in the order (“normal” mode), or shuffle the playlist each time it is loaded, and play it in this order for a whole round (“randomize” mode), or pick a random file in the playlist each time (“random” mode).
native (of type bool, which defaults to false): Use native implementation.
on_reload (of type (string) -> unit, which defaults to fun (_) -> ()): Callback called after playlist has reloaded.
prefix (of type string, which defaults to ""): Add a constant prefix to all requests. Useful for passing extra information using annotate, or for resolution through a particular protocol, such as replaygain.
reload (of type int, which defaults to 0): Amount of time (in seconds or rounds), when applicable, before which the playlist is reloaded; 0 means never.
reload_mode (of type string, which defaults to "seconds"): Unit of the reload parameter, either “never” (never reload the playlist), “rounds”, “seconds” or “watch” (reload the file whenever it is changed).
timeout (of type float, which defaults to 20.): Timeout (in sec.) for a single download.
(unlabeled) (of type string): Playlist URI.

Methods:

add (of type (request) -> bool): Add a request to the queue. Requests are resolved before being added. Returns true if the request was successfully added.
buffered (of type () -> [string * float]): Length of buffered data.
current (of type () -> request?): Get the request currently being played.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
fetch (of type () -> bool): Try feeding the queue with a new request. Returns true if successful. This method can take long to return and should usually be run in a separate thread.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
length (of type () -> int): Length of the of the playlist (the number of songs it contains).
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
queue (of type () -> [request]): Get the requests currently in the queue.
reload (of type (?empty_queue : bool, ?uri : string?) -> unit): Reload the playlist.
remaining (of type () -> float): Estimation of remaining time in the current track.
remaining_files (of type () -> [string]): Songs remaining to be played.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
set_queue (of type ([request]) -> unit): Set the queue of requests. Requests are resolved before being added to the queue. You are responsible for destroying the requests currently in the queue.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`playlist.list`

Play a list of files.

Type:

(?id : string?, ?check_next : ((request) -> bool)?, ?prefetch : int,
 ?loop : bool, ?mode : string, ?native : bool, ?on_loop : (() -> unit),
 ?on_done : (() -> unit), ?max_fail : int, ?on_fail : (() -> [string])?,
 ?timeout : float, [string]) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
check_next (of type ((request) -> bool)?, which defaults to null): Function used to filter next tracks. A candidate track is only validated if the function returns true on it. The function is called before resolution, hence metadata will only be available for requests corresponding to local files. This is typically used to avoid repetitions, but be careful: if the function rejects all attempts, the playlist will enter into a consuming loop and stop playing anything.
prefetch (of type int, which defaults to 1): How many requests should be queued in advance.
loop (of type bool, which defaults to true): Loop on the playlist.
mode (of type string, which defaults to "normal"): Play the files in the playlist either in the order (“normal” mode), or shuffle the playlist each time it is loaded, and play it in this order for a whole round (“randomize” mode), or pick a random file in the playlist each time (“random” mode).
native (of type bool, which defaults to false): Use native implementation, when available.
on_loop (of type () -> unit, which defaults to {()}): Function executed when the playlist is about to loop.
on_done (of type () -> unit, which defaults to {()}): Function executed when the playlist is finished.
max_fail (of type int, which defaults to 10): When this number of requests fail to resolve, the whole playlists is considered as failed and on_fail is called.
on_fail (of type (() -> [string])?, which defaults to null): Function executed when too many requests failed and returning the contents of a fixed playlist.
timeout (of type float, which defaults to 20.): Timeout (in sec.) for a single download.
(unlabeled) (of type [string]): Playlist.

Methods:

add (of type (request) -> bool): Add a request to the queue. Requests are resolved before being added. Returns true if the request was successfully added.
buffered (of type () -> [string * float]): Length of buffered data.
current (of type () -> request?): Get the request currently being played.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
fetch (of type () -> bool): Try feeding the queue with a new request. Returns true if successful. This method can take long to return and should usually be run in a separate thread.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
queue (of type () -> [request]): Get the requests currently in the queue.
reload (of type (?empty_queue : bool, [string]) -> unit): Reload the playlist with given list of songs.
remaining (of type () -> float): Estimation of remaining time in the current track.
remaining_files (of type () -> [string]): Songs remaining to be played.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
set_queue (of type ([request]) -> unit): Set the queue of requests. Requests are resolved before being added to the queue. You are responsible for destroying the requests currently in the queue.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`request.dynamic`

Play request dynamically created by a given function.

Type:

(?id : string?, ?available : {bool}, ?prefetch : int, ?retry_delay : {float},
 ?timeout : float, (() -> request?)) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
available (of type {bool}, which defaults to true): Whether some new requests are available (when set to false, it stops after current playing request).
prefetch (of type int, which defaults to 1): How many requests should be queued in advance.
retry_delay (of type {float}, which defaults to 0.1): Retry after a given time (in seconds) when callback returns null.
timeout (of type float, which defaults to 20.): Timeout (in sec.) for a single download.
(unlabeled) (of type () -> request?)

Methods:

add (of type (request) -> bool): Add a request to the queue. Requests are resolved before being added. Returns true if the request was successfully added.
buffered (of type () -> [string * float]): Length of buffered data.
current (of type () -> request?): Get the request currently being played.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
fetch (of type () -> bool): Try feeding the queue with a new request. Returns true if successful. This method can take long to return and should usually be run in a separate thread.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
queue (of type () -> [request]): Get the requests currently in the queue.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
set_queue (of type ([request]) -> unit): Set the queue of requests. Requests are resolved before being added to the queue. You are responsible for destroying the requests currently in the queue.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`request.once`

Play a request once and become unavailable.

Type:

(?id : string?, ?timeout : float, request) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
timeout (of type float, which defaults to 20.): Timeout in seconds for resolving the request.
(unlabeled) (of type request): Request to play.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
request (of type request): Get the request played by this source
resolve (of type () -> bool): Resolve the request (this is useful to make sure that the source will be available in advance). This function returns true if we were able to successfully perform resolution. You should use this method instead of request.resolve to make sure that the proper content type is decoded from the request.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`saw`

Generate a saw wave.

Type:

(?id : string?, ?amplitude : {float}, ?duration : float?, ?{float}) ->
source(audio=pcm*)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
amplitude (of type {float}, which defaults to 1.): Maximal value of the waveform.
duration (of type float?, which defaults to null): Duration in seconds (null means infinite).
(unlabeled) (of type {float}, which defaults to 440.): Frequency of the saw.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`sine`

Generate a sine wave.

Type:

(?id : string?, ?amplitude : {float}, ?duration : float?, ?{float}) ->
source(audio=pcm*)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
amplitude (of type {float}, which defaults to 1.): Maximal value of the waveform.
duration (of type float?, which defaults to null): Duration in seconds (null means infinite).
(unlabeled) (of type {float}, which defaults to 440.): Frequency of the sine.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`single`

Loop on a request. It never fails if the request is static, meaning that it can be fetched once. Typically, http, ftp, say requests are static, and time is not.

Type:

(?id : string?, ?fallible : bool, ?prefetch : int, ?timeout : float, string) ->
source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
fallible (of type bool, which defaults to false): Enforce fallibility of the request.
prefetch (of type int, which defaults to 1): How many requests should be queued in advance.
timeout (of type float, which defaults to 20.): Timeout (in sec.) for a single download.
(unlabeled) (of type string): URI where to find the file

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`source`

Create a source that muxes the given tracks.

Type:

(?id : string?, 'a.{metadata? : metadata, track_marks? : track_marks}) ->
source('a) where 'a is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
(unlabeled) (of type 'a.{metadata? : metadata, track_marks? : track_marks} where 'a is a set of tracks to be muxed into a source): Tracks to mux

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`source.fail`

A source that does not produce anything. No silence, no track at all.

Type:

(?id : string?) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`source.fail.init`

A source that errors during its initialization phase, used for testing and debugging.

Type:

(?id : string?) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

This function is experimental.

`square`

Generate a square wave.

Type:

(?id : string?, ?amplitude : {float}, ?duration : float?, ?{float}) ->
source(audio=pcm*)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
amplitude (of type {float}, which defaults to 1.): Maximal value of the waveform.
duration (of type float?, which defaults to null): Duration in seconds (null means infinite).
(unlabeled) (of type {float}, which defaults to 440.): Frequency of the square.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.testsrc`

Generate a test video.

Type:

(?id : string?, ?height : int, ?width : int) -> source('a)
where 'a is a set of internal tracks

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
height (of type int, which defaults to -1)
width (of type int, which defaults to -1)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

Source / Liquidsoap

`buffer`

Create a buffer between two different clocks.

Type:

(?id : string?, ?buffer : float, ?fallible : bool, ?max : float,
 ?on_start : (() -> unit), ?on_stop : (() -> unit), ?start : bool,
 source('a)) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
buffer (of type float, which defaults to 1.): Amount of data to pre-buffer, in seconds.
fallible (of type bool, which defaults to true): Allow the child source to fail.
max (of type float, which defaults to 10.): Maximum amount of buffered data, in seconds.
on_start (of type () -> unit, which defaults to {()}): Callback executed when output starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when output stops.
start (of type bool, which defaults to true): Start output as soon as it is available.
(unlabeled) (of type source('a))

Methods:

buffer_length (of type () -> int): Buffer length, in main ticks
buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`buffer.adaptative`

Create a buffer between two different clocks. The speed of the output is adapted so that no buffer underrun or overrun occurs. This wonderful behavior has a cost: the pitch of the sound might be changed a little.

Type:

(?id : string?, ?averaging : float, ?buffer : float, ?fallible : bool,
 ?limit : float, ?max : float, ?on_start : (() -> unit),
 ?on_stop : (() -> unit), ?resample : bool, ?reset : bool, ?start : bool,
 source(audio=pcm('a), 'b)) -> source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
averaging (of type float, which defaults to 30.): Length of the buffer averaging, in seconds (the time constant of the smoothing to be precise). The greater this is, the less reactive to local variations we are.
buffer (of type float, which defaults to 1.): Amount of data to prebuffer, in seconds.
fallible (of type bool, which defaults to false): Allow the child source to fail, in which case the output will be stopped until the source is available again.
limit (of type float, which defaults to 1.25): Maximum acceleration or deceleration factor, ie how fast or slow we can be compared to realtime.
max (of type float, which defaults to 10.): Maximum amount of buffered data, in seconds.
on_start (of type () -> unit, which defaults to {()}): Callback executed when output starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when output stops.
resample (of type bool, which defaults to true): Use proper resampling instead of simply duplicating samples.
reset (of type bool, which defaults to false): Reset speed estimation to 1 when the source becomes available again (resuming from a buffer underflow).
start (of type bool, which defaults to true): Start output as soon as it is available.
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Current buffer duration, in seconds.
elapsed (of type () -> float): Elapsed time in the current track.
estimated (of type () -> float): Current smoothed buffer duration, in seconds.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
ratio (of type () -> float): Get the current scaling ratio.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

This function is experimental.

`source.drop`

Animate the source as fast as possible, dropping its output.

Type:

(source('a)) -> unit

Arguments:

(unlabeled) (of type source('a)): Source to animate.

This function is experimental.

`source.dump`

Immediately encode the whole contents of a source into a file.

Type:

(format('a), string, source('a)) -> unit

Arguments:

(unlabeled) (of type format('a)): Encoding format.
(unlabeled) (of type string): Name of the file.
(unlabeled) (of type source('a)): Source to encode.

This function is experimental.

`source.duration`

Estimation of the duration in the current track.

Type:

(source('a)) -> float

Arguments:

(unlabeled) (of type source('a))

`source.elapsed`

Elapsed time in the current track.

Type:

(source('a)) -> float

Arguments:

(unlabeled) (of type source('a))

`source.fallible`

Indicate if a source may fail, i.e. may not be ready to stream.

Type:

(source('a)) -> bool

Arguments:

(unlabeled) (of type source('a))

`source.id`

Get the identifier of a source.

Type:

(source('a)) -> string

Arguments:

(unlabeled) (of type source('a))

`source.init`

Simultaneously initialize sources, return the sublist of sources that failed to initialize.

Type:

([source('a)]) -> [source('a)]

Arguments:

(unlabeled) (of type [source('a)])

This function is experimental.

`source.is_ready`

Indicate if a source is ready to stream (we also say that it is available), or currently streaming.

Type:

(source('a)) -> bool

Arguments:

(unlabeled) (of type source('a))

`source.on_shutdown`

Type:

(source('a), (() -> unit)) -> unit

Arguments:

(unlabeled) (of type source('a))
(unlabeled) (of type () -> unit)

`source.remaining`

Estimation of remaining time in the current track.

Type:

(source('a)) -> float

Arguments:

(unlabeled) (of type source('a))

`source.seek`

Seek forward, in seconds. Returns the amount of time effectively seeked.

Type:

(source('a), float) -> float

Arguments:

(unlabeled) (of type source('a))
(unlabeled) (of type float)

`source.set_name`

Set the name of an operator.

Type:

(source('a), string) -> unit

Arguments:

(unlabeled) (of type source('a))
(unlabeled) (of type string)

`source.skip`

Skip to the next track.

Type:

(source('a)) -> unit

Arguments:

(unlabeled) (of type source('a))

`source.time`

Get a source’s time, based on its assigned clock

Type:

(source('a)) -> float

Arguments:

(unlabeled) (of type source('a))

Source / MIDI processing

`midi.chord`

Generate a chord.

Type:

(?id : string?, ?metadata : string, source('a)) ->
source(midi=midi(channels=1), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
metadata (of type string, which defaults to "chord"): Name of the metadata containing the chords.
(unlabeled) (of type source('a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`midi.merge_all`

Merge all MIDI tracks in one.

Type:

(?id : string?, ?track_out : int, source(midi=midi('a), 'b)) ->
source(midi=midi('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
track_out (of type int, which defaults to 0): Destination track.
(unlabeled) (of type source(midi=midi('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`midi.remove`

Remove MIDI tracks.

Type:

(?id : string?, [int], source(midi=midi('a), 'b)) -> source(midi=midi('a),
'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
(unlabeled) (of type [int]): Tracks to remove.
(unlabeled) (of type source(midi=midi('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

Source / Output

`ffmpeg.filter.audio_video.output`

Return a source with audio and video from a filter’s output.

Type:

(?id : string?, ffmpeg.filter.graph, 'b
 .{tracks : () -> 'a.{audio : ffmpeg.filter.audio}}, 'd
 .{tracks : () -> 'c.{video : ffmpeg.filter.video}}) ->
source(audio=ffmpeg.audio.raw('e), video=ffmpeg.video.raw('f))

Arguments:

id (of type string?, which defaults to null)
(unlabeled) (of type ffmpeg.filter.graph): Force the value of the source ID.
(unlabeled) (of type 'b.{tracks : () -> 'a.{audio : ffmpeg.filter.audio}})
(unlabeled) (of type 'd.{tracks : () -> 'c.{video : ffmpeg.filter.video}})

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`output`

Output a stream using the default operator. The input source does not need to be infallible, blank will just be played during failures.

Type:

(?id : string?, ?fallible : bool, ?on_start : (() -> unit),
 ?on_stop : (() -> unit), ?start : bool, source(audio=pcm('A))) -> unit

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
fallible (of type bool, which defaults to true): Allow the child source to fail, in which case the output will be (temporarily) stopped.
on_start (of type () -> unit, which defaults to {()}): Callback executed when outputting starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when outputting stops.
start (of type bool, which defaults to true): Automatically start outputting whenever possible. If true, an infallible (normal) output will start outputting as soon as it is created, and a fallible output will (re)start as soon as its source becomes available for streaming.
(unlabeled) (of type source(audio=pcm('A))): Source to play.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
stop (of type () -> unit): Ask the source or output to stop.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`output.alsa`

Output the source’s stream to an ALSA output device.

Type:

(?id : string?, ?bufferize : bool, ?clock_safe : bool, ?device : string,
 ?fallible : bool, ?on_start : (() -> unit), ?on_stop : (() -> unit),
 ?start : bool, source(audio=pcm('a), 'b)) -> unit

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
bufferize (of type bool, which defaults to true): Bufferize output
clock_safe (of type bool, which defaults to true): Force the use of the dedicated ALSA clock
device (of type string, which defaults to "default"): Alsa device to use
fallible (of type bool, which defaults to false): Allow the child source to fail, in which case the output will be stopped until the source is available again.
on_start (of type () -> unit, which defaults to {()}): Callback executed when output starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when output stops.
start (of type bool, which defaults to true): Start output as soon as it is available.
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
stop (of type () -> unit): Ask the source or output to stop.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`output.ao`

Output stream to local sound card using libao.

Type:

(?id : string?, ?buffer_size : int, ?channels_matrix : string,
 ?clock_safe : bool, ?driver : string, ?fallible : bool,
 ?on_start : (() -> unit), ?on_stop : (() -> unit),
 ?options : [string * string], ?start : bool, source(audio=pcm('a), 'b)) ->
unit

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
buffer_size (of type int, which defaults to 2): Set buffer size, in frames.
channels_matrix (of type string, which defaults to ""): Output channels matrix, “” for AO’s default.
clock_safe (of type bool, which defaults to true): Use the dedicated AO clock.
driver (of type string, which defaults to ""): Driver to be used, “” for AO’s default.
fallible (of type bool, which defaults to false): Allow the child source to fail, in which case the output will be stopped until the source is available again.
on_start (of type () -> unit, which defaults to {()}): Callback executed when output starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when output stops.
options (of type [string * string], which defaults to []): List of parameters, depends on the driver.
start (of type bool, which defaults to true): Start output as soon as it is available.
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
stop (of type () -> unit): Ask the source or output to stop.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`output.audio_video`

Output a stream with audio and video using the default operator. The input source does not need to be infallible, blank will just be played during failures.

Type:

(?id : string?, ?fallible : bool, ?on_start : (() -> unit),
 ?on_stop : (() -> unit), ?start : bool, source(audio=pcm('A),
 video=canvas('a))) -> unit

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
fallible (of type bool, which defaults to true): Allow the child source to fail, in which case the output will be (temporarily) stopped.
on_start (of type () -> unit, which defaults to {()}): Callback executed when outputting starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when outputting stops.
start (of type bool, which defaults to true): Automatically start outputting whenever possible. If true, an infallible (normal) output will start outputting as soon as it is created, and a fallible output will (re)start as soon as its source becomes available for streaming.
(unlabeled) (of type source(audio=pcm('A), video=canvas('a))): Source to play.

`output.dummy`

Dummy output: computes the stream, without actually using it.

Type:

(?id : string?, ?fallible : bool, ?on_start : (() -> unit),
 ?on_stop : (() -> unit), ?start : bool, source('a)) -> unit

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
fallible (of type bool, which defaults to false): Allow the child source to fail, in which case the output will be stopped until the source is available again.
on_start (of type () -> unit, which defaults to {()}): Callback executed when output starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when output stops.
start (of type bool, which defaults to true): Start output as soon as it is available.
(unlabeled) (of type source('a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
stop (of type () -> unit): Ask the source or output to stop.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`output.external`

Send the stream to a process’ standard input.

Type:

(?id : string?, ?fallible : bool, ?flush : bool, ?on_reopen : (() -> unit),
 ?on_start : (() -> unit), ?on_stop : (() -> unit), ?reopen_delay : {float},
 ?reopen_on_error : ((error
                      .{
                        kind : string,
                        message : string,
                        trace : [
                                 {
                                   position_end : 
                                   {
                                     character_offset : int,
                                     filename : string,
                                     line_number : int
                                   },
                                   position_start : 
                                   {
                                     character_offset : int,
                                     filename : string,
                                     line_number : int
                                   },
                                   to_string : (?prefix : string) -> string
                                 }]
                      }?) -> float?),
 ?reopen_on_metadata : (([string * string]) -> bool),
 ?reopen_when : (() -> bool), ?self_sync : bool, ?start : bool, format('a),
 {string}, source('a)) -> unit

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
fallible (of type bool, which defaults to false): Allow the child source to fail, in which case the output will be stopped until the source is available again.
flush (of type bool, which defaults to false): Perform a flush after each write.
on_reopen (of type () -> unit, which defaults to {()}): Callback executed when the output is reopened.
on_start (of type () -> unit, which defaults to {()}): Callback executed when output starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when output stops.
reopen_delay (of type {float}, which defaults to 120.): Prevent re-opening within that delay, in seconds. Only applies to reopen_when.
reopen_on_error (of type (error .{ kind : string, message : string, trace : [ { position_end : {character_offset : int, filename : string, line_number : int }, position_start : {character_offset : int, filename : string, line_number : int }, to_string : (?prefix : string) -> string }] }?) -> float?, which defaults to <fun>): Callback called when there is an error. Error is raised when returning null. Otherwise, the file is reopened after the returned value, in seconds.
reopen_on_metadata (of type ([string * string]) -> bool, which defaults to fun (_) -> false): Callback called on metadata. If returned value is true, the file is reopened.
reopen_when (of type () -> bool, which defaults to {false}): Callback called on each frame. If returned value is true, the file is reopened.
self_sync (of type bool, which defaults to false): Set to true if the process is expected to control the output’s latency. Typical example: ffmpeg with the -re command-line option.
start (of type bool, which defaults to true): Start output as soon as it is available.
(unlabeled) (of type format('a)): Process to pipe data to.
(unlabeled) (of type {string}): Encoding format.
(unlabeled) (of type source('a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
reopen (of type () -> unit): Reopen the output pipe. The actual reopening happens the next time the output has some data to output.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
stop (of type () -> unit): Ask the source or output to stop.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`output.file`

Output the source stream to a file.

Type:

(?id : string?, ?append : bool, ?dir_perm : int, ?fallible : bool,
 ?flush : bool, ?on_close : ((string) -> unit), ?on_reopen : (() -> unit),
 ?on_start : (() -> unit), ?on_stop : (() -> unit), ?perm : int,
 ?reopen_delay : {float},
 ?reopen_on_error : ((error
                      .{
                        kind : string,
                        message : string,
                        trace : [
                                 {
                                   position_end : 
                                   {
                                     character_offset : int,
                                     filename : string,
                                     line_number : int
                                   },
                                   position_start : 
                                   {
                                     character_offset : int,
                                     filename : string,
                                     line_number : int
                                   },
                                   to_string : (?prefix : string) -> string
                                 }]
                      }?) -> float?),
 ?reopen_on_metadata : (([string * string]) -> bool),
 ?reopen_when : (() -> bool), ?start : bool, format('a), {string},
 source('a)) -> unit

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
append (of type bool, which defaults to false): Do not truncate but append in the file if it exists.
dir_perm (of type int, which defaults to 511): Permission of the directories if some have to be created, up to umask. Although you can enter values in octal notation (0oXXX) they will be displayed in decimal (for instance, 0o777 = 7×8^2 + 7×8 + 7 = 511).
fallible (of type bool, which defaults to false): Allow the child source to fail, in which case the output will be stopped until the source is available again.
flush (of type bool, which defaults to false): Perform a flush after each write.
on_close (of type (string) -> unit, which defaults to fun (_) -> ()): This function will be called for each file, after that it is finished and closed. The filename will be passed as argument.
on_reopen (of type () -> unit, which defaults to {()}): Callback executed when the output is reopened.
on_start (of type () -> unit, which defaults to {()}): Callback executed when output starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when output stops.
perm (of type int, which defaults to 438): Permission of the file if it has to be created, up to umask. You can and should write this number in octal notation: 0oXXX. The default value is however displayed in decimal (0o666 = 6×8^2 + 6×8 + 6 = 438).
reopen_delay (of type {float}, which defaults to 120.): Prevent re-opening within that delay, in seconds. Only applies to reopen_when.
reopen_on_error (of type (error .{ kind : string, message : string, trace : [ { position_end : {character_offset : int, filename : string, line_number : int }, position_start : {character_offset : int, filename : string, line_number : int }, to_string : (?prefix : string) -> string }] }?) -> float?, which defaults to <fun>): Callback called when there is an error. Error is raised when returning null. Otherwise, the file is reopened after the returned value, in seconds.
reopen_on_metadata (of type ([string * string]) -> bool, which defaults to fun (_) -> false): Callback called on metadata. If returned value is true, the file is reopened.
reopen_when (of type () -> bool, which defaults to {false}): Callback called on each frame. If returned value is true, the file is reopened.
start (of type bool, which defaults to true): Start output as soon as it is available.
(unlabeled) (of type format('a)): Encoding format.
(unlabeled) (of type {string}): Filename where to output the stream.
(unlabeled) (of type source('a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
reopen (of type () -> unit): Reopen the output pipe. The actual reopening happens the next time the output has some data to output.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
stop (of type () -> unit): Ask the source or output to stop.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`output.file.hls`

Output the source stream to an HTTP live stream served from a local directory.

Type:

(?id : string?, ?dir_perm : int, ?extra_tags : [string], ?fallible : bool,
 ?on_file_change : ((state : string, string) -> unit),
 ?on_start : (() -> unit), ?on_stop : (() -> unit), ?perm : int,
 ?persist_at : string?, ?playlist : string, ?prefix : string,
 ?segment_duration : float,
 ?segment_name : ((position : int, extname : string, string) -> string),
 ?segments : int, ?segments_overhead : int, ?start : bool,
 ?strict_persist : bool, string,
 [string * format('a)
  .{
    bandwidth? : int,
    codecs? : string,
    extname? : string,
    extra_tags? : [string],
    id3? : bool,
    id3_version? : int,
    replay_id3? : bool,
    video_size? : int * int
  }],
 source('a)) -> unit

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
dir_perm (of type int, which defaults to 511): Permission of the directories if some have to be created, up to umask. Although you can enter values in octal notation (0oXXX) they will be displayed in decimal (for instance, 0o777 = 7×8^2 + 7×8 + 7 = 511).
extra_tags (of type [string], which defaults to []): Extra tags to insert into the main playlist.
fallible (of type bool, which defaults to false): Allow the child source to fail, in which case the output will be stopped until the source is available again.
on_file_change (of type (state : string, string) -> unit, which defaults to fun (~state=_,_) -> ()): Callback executed when a file changes. state is one of: "opened", "closed" or "deleted", second argument is file path. Typical use: upload files to a CDN when done writing ("close" state and remove when "deleted").
on_start (of type () -> unit, which defaults to {()}): Callback executed when output starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when output stops.
perm (of type int, which defaults to 438): Permission of the created files, up to umask. You can and should write this number in octal notation: 0oXXX. The default value is however displayed in decimal (0o666 = 6×8^2 + 4×8 + 4 = 412).
persist_at (of type string?, which defaults to null): Location of the configuration file used to restart the output. Relative paths are assumed to be with regard to the directory for generated file.
playlist (of type string, which defaults to "stream.m3u8"): Playlist name (m3u8 extension is recommended).
prefix (of type string, which defaults to ""): Prefix for each files in playlists.
segment_duration (of type float, which defaults to 10.): Segment duration (in seconds).
segment_name (of type (position : int, extname : string, string) -> string, which defaults to <fun>): Segment name. Default: fun (~position,~extname,stream_name) -> "#{stream_name}_#{position}.#{extname}"
segments (of type int, which defaults to 10): Number of segments per playlist.
segments_overhead (of type int, which defaults to 5): Number of segments to keep after they have been featured in the live playlist.
start (of type bool, which defaults to true): Start output as soon as it is available.
strict_persist (of type bool, which defaults to false): Fail if an invalid saved state exists.
(unlabeled) (of type string): Directory for generated files.
(unlabeled) (of type [string * format('a) .{ bandwidth? : int, codecs? : string, extname? : string, extra_tags? : [string], id3? : bool, id3_version? : int, replay_id3? : bool, video_size? : int * int }]): List of specifications for each stream: (name, format).
(unlabeled) (of type source('a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
stop (of type () -> unit): Ask the source or output to stop.
streams (of type () -> [ { bandwidth : int, codecs : string, discontinuity_count : int, encoder : format('A), extname : string, extra_tags : [string], id3_enabled : bool, insert_tag : (string) -> unit, name : string, replay_id3 : bool, video_size : {height : int, width : int }? }]): Output streams
time (of type () -> float): Get a source’s time, based on its assigned clock.

`output.harbor`

Encode and output the stream using the harbor server.

Type:

(?id : string?, ?auth : ((address : string, string, string) -> bool)?,
 ?buffer : int, ?burst : int, ?chunk : int, ?dumpfile : string?,
 ?encoding : string, ?fallible : bool, ?format : string,
 ?headers : [string * string], ?metaint : int, mount : string,
 ?on_connect : ((headers : [string * string], uri : string,
                 protocol : string, string) -> unit),
 ?on_disconnect : ((string) -> unit), ?on_start : (() -> unit),
 ?on_stop : (() -> unit), ?password : string?, ?port : int, ?start : bool,
 ?timeout : float, ?transport : http_transport, ?url : string?,
 ?user : string?, format('a), source('a)) -> unit

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
auth (of type ((address : string, string, string) -> bool)?, which defaults to null): Authentication function. f(~address,login,password) returns true if the user should be granted access for this login. When defined, user and password arguments are not taken in account.
buffer (of type int, which defaults to 327675): Maximum buffer per-client.
burst (of type int, which defaults to 65534): Initial burst of data sent to the client.
chunk (of type int, which defaults to 4096): Send data to clients using chunks of at least this length.
dumpfile (of type string?, which defaults to null): Dump stream to file, for debugging purpose. Disabled if null.
encoding (of type string, which defaults to ""): Encoding used to send metadata. If empty, defaults to “UTF-8”
fallible (of type bool, which defaults to false): Allow the child source to fail, in which case the output will be stopped until the source is available again.
format (of type string, which defaults to ""): Format, e.g. “audio/ogg”. When empty, the encoder is used to guess.
headers (of type [string * string], which defaults to []): Additional headers.
metaint (of type int, which defaults to 8192): Interval used to send ICY metadata
mount (of type string)
on_connect (of type (headers : [string * string], uri : string, protocol : string, string) -> unit, which defaults to fun (~headers=_,~uri=_,~protocol=_,_) -> ()): Callback executed when connection is established (takes headers, connection uri, protocol and client’s IP as arguments).
on_disconnect (of type (string) -> unit, which defaults to fun (_) -> ()): Callback executed when connection stops (takes client’s IP as argument).
on_start (of type () -> unit, which defaults to {()}): Callback executed when output starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when output stops.
password (of type string?, which defaults to null): Password for client connection. A user must also be set. We check for this password is checked unless an auth function is defined, which is used in this case.
port (of type int, which defaults to 8000)
start (of type bool, which defaults to true): Start output as soon as it is available.
timeout (of type float, which defaults to 30.): Timeout for network operations (in seconds).
transport (of type http_transport, which defaults to <unix_transport>): Http transport. Use http.transport.ssl or http.transport.secure_transport, when available, to enable HTTPS output
url (of type string?, which defaults to null)
user (of type string?, which defaults to null): User for client connection. You also need to setup a password.
(unlabeled) (of type format('a)): Encoding format.
(unlabeled) (of type source('a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
stop (of type () -> unit): Ask the source or output to stop.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`output.harbor.hls`

Output the source stream to an HTTP live stream served from the harbor HTTP server.

Type:

(?id : string?, ?dir_perm : int, ?extra_tags : [string], ?fallible : bool,
 ?on_file_change : ((state : string, string) -> unit),
 ?on_start : (() -> unit), ?on_stop : (() -> unit), ?perm : int,
 ?persist_at : string?, ?playlist : string, ?prefix : string,
 ?segment_duration : float, ?segments : int, ?segments_overhead : int,
 ?start : bool, ?strict_persist : bool,
 ?segment_name : ((position : int, extname : string, string) -> string),
 ?headers : [string * string], ?port : int, ?path : string,
 ?tmpdir : string?, ?transport : http_transport
 .{default_port : int, name : string, protocol : string},
 [string * format('a)], source('a)) -> unit

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
dir_perm (of type int, which defaults to 511): Permission of the directories if some have to be created, up to umask. Although you can enter values in octal notation (0oXXX) they will be displayed in decimal (for instance, 0o777 = 7×8^2 + 7×8 + 7 = 511).
extra_tags (of type [string], which defaults to []): Extra tags to insert into the main playlist.
fallible (of type bool, which defaults to false): Allow the child source to fail, in which case the output will be stopped until the source is available again.
on_file_change (of type (state : string, string) -> unit, which defaults to fun (~state=_,_) -> ()): Callback executed when a file changes. state is one of: "opened", "closed" or "deleted", second argument is file path. Typical use: upload files to a CDN when done writing ("close" state and remove when "deleted").
on_start (of type () -> unit, which defaults to {()}): Callback executed when output starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when output stops.
perm (of type int, which defaults to 438): Permission of the created files, up to umask. You can and should write this number in octal notation: 0oXXX. The default value is however displayed in decimal (0o666 = 6×8^2 + 4×8 + 4 = 412).
persist_at (of type string?, which defaults to null): Location of the configuration file used to restart the output. Relative paths are assumed to be with regard to the directory for generated file.
playlist (of type string, which defaults to "stream.m3u8"): Playlist name (m3u8 extension is recommended).
prefix (of type string, which defaults to ""): Prefix for each files in playlists.
segment_duration (of type float, which defaults to 10.): Segment duration (in seconds).
segments (of type int, which defaults to 10): Number of segments per playlist.
segments_overhead (of type int, which defaults to 5): Number of segments to keep after they have been featured in the live playlist.
start (of type bool, which defaults to true): Start output as soon as it is available.
strict_persist (of type bool, which defaults to false): Fail if an invalid saved state exists.
segment_name (of type (position : int, extname : string, string) -> string, which defaults to <fun>): Segment name. Default: fun (~position,~extname,stream_name) -> "#{stream_name}_#{position}.#{extname}"
headers (of type [string * string], which defaults to [("Access-Control-Allow-Origin", "*")]): Default response headers.
port (of type int, which defaults to 8000): Port for incoming harbor (http) connections.
path (of type string, which defaults to "/"): Base path for hls URIs.
tmpdir (of type string?, which defaults to null): Directory for generated files.
transport (of type http_transport.{default_port : int, name : string, protocol : string}, which defaults to <unix_transport>.{default_port=80, protocol="http", name="unix"}): Http transport. Use http.transport.ssl or http.transport.secure_transport, when available, to enable HTTPS output
(unlabeled) (of type [string * format('a)]): List of specifications for each stream: (name, format).
(unlabeled) (of type source('a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
stop (of type () -> unit): Ask the source or output to stop.
streams (of type () -> [ { bandwidth : int, codecs : string, discontinuity_count : int, encoder : format('A), extname : string, extra_tags : [string], id3_enabled : bool, insert_tag : (string) -> unit, name : string, replay_id3 : bool, video_size : {height : int, width : int }? }]): Output streams
time (of type () -> float): Get a source’s time, based on its assigned clock.

`output.icecast`

Encode and output the stream to an icecast server.

Type:

(?id : string?, ?chunked : bool, ?connection_timeout : float,
 ?description : string?, ?dumpfile : string?, ?encoding : string?,
 ?fallible : bool, ?format : string, ?genre : string?,
 ?headers : [string * string], ?host : string, ?icy_metadata : [string],
 ?icy_song : (([string * string]) -> string?), ?method : string,
 mount : string, ?name : string?, ?on_connect : (() -> unit),
 ?on_disconnect : (() -> unit), ?on_error : ((string) -> float),
 ?on_start : (() -> unit), ?on_stop : (() -> unit), ?password : string,
 ?port : int, ?public : bool, ?send_icy_metadata : bool?, ?start : bool,
 ?timeout : float, ?transport : http_transport, ?url : string?,
 ?user : string?, format('a), source('a)) -> unit

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
chunked (of type bool, which defaults to false): Used chunked transfer with the ‘http(s)’ protocol.
connection_timeout (of type float, which defaults to 5.): Timeout for establishing network connections (disabled is negative).
description (of type string?, which defaults to null)
dumpfile (of type string?, which defaults to null): Dump stream to file, for debugging purpose. Disabled if null.
encoding (of type string?, which defaults to null): Encoding used to send metadata and stream info (name, genre and description). If null, defaults to “UTF-8”.
fallible (of type bool, which defaults to false): Allow the child source to fail, in which case the output will be stopped until the source is available again.
format (of type string, which defaults to ""): Format, e.g. “audio/ogg”. When empty, the encoder is used to guess.
genre (of type string?, which defaults to null)
headers (of type [string * string], which defaults to [("User-Agent", "Liquidsoap/2.2.0 (Unix; OCaml 4.14.1)")]): Additional headers.
host (of type string, which defaults to "localhost")
icy_metadata (of type [string], which defaults to ["song", "title", "artist", "genre", "date", "album", "tracknum", "comment", "dj", "next"]): List of metadata to send with ICY metadata update
icy_song (of type ([string * string]) -> string?, which defaults to <fun>): Function used to generate the default icy “song” metadata. Metadata is not added when returning null. Default: $(artist) - $(title) if both are defined, otherwise artist or title if either is defined or null.
method (of type string, which defaults to "source"): Method to use with the ‘http(s)’ protocol. One of: ‘source’, ‘put’ or ‘post’.
mount (of type string): Source mount point.
name (of type string?, which defaults to null)
on_connect (of type () -> unit, which defaults to {()}): Callback executed when connection is established.
on_disconnect (of type () -> unit, which defaults to {()}): Callback executed when connection stops.
on_error (of type (string) -> float, which defaults to fun (_) -> 3.): Callback executed when an error happens. The callback receives a string representation of the error that occurred and returns a float. If returned value is positive, connection will be tried again after this amount of time (in seconds).
on_start (of type () -> unit, which defaults to {()}): Callback executed when output starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when output stops.
password (of type string, which defaults to "hackme")
port (of type int, which defaults to 8000)
public (of type bool, which defaults to true)
send_icy_metadata (of type bool?, which defaults to null): Send new metadata using the ICY protocol. Guessed when null
start (of type bool, which defaults to true): Start output as soon as it is available.
timeout (of type float, which defaults to 30.): Timeout for network read and write.
transport (of type http_transport, which defaults to <unix_transport>): Http transport. Use http.transport.ssl or http.transport.secure_transport, when available, to enable HTTPS output
url (of type string?, which defaults to null)
user (of type string?, which defaults to null): User for shout source connection. Defaults to “source” for icecast connections. Useful only in special cases, like with per-mountpoint users.
(unlabeled) (of type format('a)): Encoding format.
(unlabeled) (of type source('a)): The source to output

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
stop (of type () -> unit): Ask the source or output to stop.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`output.jack`

Output stream to jack.

Type:

(?id : string?, ?buffer_size : int, ?clock_safe : bool, ?fallible : bool,
 ?on_start : (() -> unit), ?on_stop : (() -> unit), ?server : string,
 ?start : bool, source(audio=pcm('a), 'b)) -> unit

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
buffer_size (of type int, which defaults to 2): Set buffer size, in frames.
clock_safe (of type bool, which defaults to true): Force the use of the dedicated bjack clock.
fallible (of type bool, which defaults to false): Allow the child source to fail, in which case the output will be stopped until the source is available again.
on_start (of type () -> unit, which defaults to {()}): Callback executed when output starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when output stops.
server (of type string, which defaults to ""): Jack server to connect to.
start (of type bool, which defaults to true): Start output as soon as it is available.
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
stop (of type () -> unit): Ask the source or output to stop.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`output.oss`

Output the source’s stream to an OSS output device.

Type:

(?id : string?, ?clock_safe : bool, ?device : string, ?fallible : bool,
 ?on_start : (() -> unit), ?on_stop : (() -> unit), ?start : bool,
 source(audio=pcm('a), 'b)) -> unit

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
clock_safe (of type bool, which defaults to true): Force the use of the dedicated OSS clock.
device (of type string, which defaults to "/dev/dsp"): OSS device to use.
fallible (of type bool, which defaults to false): Allow the child source to fail, in which case the output will be stopped until the source is available again.
on_start (of type () -> unit, which defaults to {()}): Callback executed when output starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when output stops.
start (of type bool, which defaults to true): Start output as soon as it is available.
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
stop (of type () -> unit): Ask the source or output to stop.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`output.portaudio`

Output the source’s stream to a portaudio output device.

Type:

(?id : string?, ?buflen : int, ?clock_safe : bool, ?device_id : int?,
 ?fallible : bool, ?latency : float?, ?on_start : (() -> unit),
 ?on_stop : (() -> unit), ?start : bool, source(audio=pcm('a), 'b)) -> unit

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
buflen (of type int, which defaults to 256): Length of a buffer in samples.
clock_safe (of type bool, which defaults to true): Force the use of the dedicated Portaudio clock.
device_id (of type int?, which defaults to null): Device ID. Uses default device if null.
fallible (of type bool, which defaults to false): Allow the child source to fail, in which case the output will be stopped until the source is available again.
latency (of type float?, which defaults to null): Device latency. Only used when specifying device ID.
on_start (of type () -> unit, which defaults to {()}): Callback executed when output starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when output stops.
start (of type bool, which defaults to true): Start output as soon as it is available.
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
stop (of type () -> unit): Ask the source or output to stop.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`output.pulseaudio`

Output the source’s stream to a pulseaudio output device.

Type:

(?id : string?, ?client : string, ?clock_safe : bool, ?device : string,
 ?fallible : bool, ?on_start : (() -> unit), ?on_stop : (() -> unit),
 ?start : bool, source(audio=pcm('a), 'b)) -> unit

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
client (of type string, which defaults to "liquidsoap")
clock_safe (of type bool, which defaults to true): Force the use of the dedicated Pulseaudio clock.
device (of type string, which defaults to ""): Device to use. Uses default if set to ““.
fallible (of type bool, which defaults to false): Allow the child source to fail, in which case the output will be stopped until the source is available again.
on_start (of type () -> unit, which defaults to {()}): Callback executed when output starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when output stops.
start (of type bool, which defaults to true): Start output as soon as it is available.
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
stop (of type () -> unit): Ask the source or output to stop.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`output.sdl`

Display a video using SDL.

Type:

(?id : string?, ?fallible : bool, ?on_start : (() -> unit),
 ?on_stop : (() -> unit), ?start : bool, source(video=canvas('a), 'b)) ->
unit

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
fallible (of type bool, which defaults to false): Allow the child source to fail, in which case the output will be stopped until the source is available again.
on_start (of type () -> unit, which defaults to {()}): Callback executed when output starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when output stops.
start (of type bool, which defaults to true): Start output as soon as it is available.
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
stop (of type () -> unit): Ask the source or output to stop.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`output.sdl.has_video`

Check whether video output is available with SDL.

Type:

() -> bool

`output.shoutcast`

Encode and output the stream to a shoutcast server.

Type:

(?id : string?, ?chunked : bool, ?connection_timeout : float,
 ?dumpfile : string?, ?encoding : string?, ?fallible : bool,
 ?format : string, ?genre : string?, ?headers : [string * string],
 ?host : string, ?icy_id : int, ?icy_metadata : [string],
 ?icy_song : (([string * string]) -> string?), ?name : string?,
 ?on_connect : (() -> unit), ?on_disconnect : (() -> unit),
 ?on_error : ((string) -> float), ?on_start : (() -> unit),
 ?on_stop : (() -> unit), ?password : string, ?port : int, ?public : bool,
 ?send_icy_metadata : bool?, ?start : bool, ?timeout : float,
 ?transport : http_transport, ?url : string?, ?user : string?,
 ?icy_reset : bool, ?dj : (() -> string), ?aim : string, ?icq : string,
 ?irc : string, format('a), source('a)) -> unit
where 'a is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
chunked (of type bool, which defaults to false): Used chunked transfer with the ‘http(s)’ protocol.
connection_timeout (of type float, which defaults to 5.): Timeout for establishing network connections (disabled is negative).
dumpfile (of type string?, which defaults to null): Dump stream to file, for debugging purpose. Disabled if null.
encoding (of type string?, which defaults to null): Encoding used to send metadata and stream info (name, genre and description). If null, defaults to “UTF-8”.
fallible (of type bool, which defaults to false): Allow the child source to fail, in which case the output will be stopped until the source is available again.
format (of type string, which defaults to ""): Format, e.g. “audio/ogg”. When empty, the encoder is used to guess.
genre (of type string?, which defaults to null)
headers (of type [string * string], which defaults to [("User-Agent", "Liquidsoap/2.2.0 (Unix; OCaml 4.14.1)")]): Additional headers.
host (of type string, which defaults to "localhost")
icy_id (of type int, which defaults to 1): Shoutcast source ID.
icy_metadata (of type [string], which defaults to ["song", "title", "artist", "genre", "date", "album", "tracknum", "comment", "dj", "next"]): List of metadata to send with ICY metadata update
icy_song (of type ([string * string]) -> string?, which defaults to <fun>): Function used to generate the default icy “song” metadata. Metadata is not added when returning null. Default: $(artist) - $(title) if both are defined, otherwise artist or title if either is defined or null.
name (of type string?, which defaults to null)
on_connect (of type () -> unit, which defaults to {()}): Callback executed when connection is established.
on_disconnect (of type () -> unit, which defaults to {()}): Callback executed when connection stops.
on_error (of type (string) -> float, which defaults to fun (_) -> 3.): Callback executed when an error happens. The callback receives a string representation of the error that occurred and returns a float. If returned value is positive, connection will be tried again after this amount of time (in seconds).
on_start (of type () -> unit, which defaults to {()}): Callback executed when output starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when output stops.
password (of type string, which defaults to "hackme")
port (of type int, which defaults to 8000)
public (of type bool, which defaults to true)
send_icy_metadata (of type bool?, which defaults to null): Send new metadata using the ICY protocol. Guessed when null
start (of type bool, which defaults to true): Start output as soon as it is available.
timeout (of type float, which defaults to 30.): Timeout for network read and write.
transport (of type http_transport, which defaults to <unix_transport>): Http transport. Use http.transport.ssl or http.transport.secure_transport, when available, to enable HTTPS output
url (of type string?, which defaults to null)
user (of type string?, which defaults to null): User for shout source connection. Defaults to “source” for icecast connections. Useful only in special cases, like with per-mountpoint users.
icy_reset (of type bool, which defaults to true): Reset shoutcast source buffer upon connecting (necessary for NSV).
dj (of type () -> string, which defaults to {""}): Callback to set dj name.
aim (of type string, which defaults to "")
icq (of type string, which defaults to "")
irc (of type string, which defaults to "")
(unlabeled) (of type format('a) where 'a is a set of tracks to be muxed into a source): Encoding format. Should be mp3 or AAC(+).
(unlabeled) (of type source('a) where 'a is a set of tracks to be muxed into a source): The source to output

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
stop (of type () -> unit): Ask the source or output to stop.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`output.srt`

Send a SRT stream to a distant agent.

Type:

(?id : string?, ?bind_address : string, ?connection_timeout : float?,
 ?enforced_encryption : bool?, ?fallible : bool, ?host : string,
 ?listen_callback : ((hs_version : int, peeraddr : string,
                      streamid : string?, srt_socket
                      .{
                        bistats : (?clear : bool?, ?instantaneous : bool?) -> 
                                  {
                                    byteAvailRcvBuf : int,
                                    byteAvailSndBuf : int,
                                    byteMSS : int,
                                    byteRcvBuf : int,
                                    byteRcvDrop : int,
                                    byteRcvDropTotal : int,
                                    byteRcvUndecrypt : int,
                                    byteRcvUndecryptTotal : int,
                                    byteRecv : int,
                                    byteRecvTotal : int,
                                    byteRetrans : int,
                                    byteRetransTotal : int,
                                    byteSent : int,
                                    byteSentTotal : int,
                                    byteSndBuf : int,
                                    byteSndDrop : int,
                                    byteSndDropTotal : int,
                                    mbpsBandwidth : float,
                                    mbpsMaxBW : float,
                                    mbpsRecvRate : float,
                                    mbpsSendRate : float,
                                    msRTT : float,
                                    msRcvBuf : int,
                                    msRcvTsbPdDelay : int,
                                    msSndBuf : int,
                                    msSndTsbPdDelay : int,
                                    msTimeStamp : int,
                                    pktCongestionWindow : int,
                                    pktFlightSize : int,
                                    pktFlowWindow : int,
                                    pktRcvAvgBelatedTime : float,
                                    pktRcvBelated : int,
                                    pktRcvBuf : int,
                                    pktRcvDrop : int,
                                    pktRcvDropTotal : int,
                                    pktRcvFilterExtra : int,
                                    pktRcvFilterExtraTotal : int,
                                    pktRcvFilterLoss : int,
                                    pktRcvFilterLossTotal : int,
                                    pktRcvFilterSupply : int,
                                    pktRcvFilterSupplyTotal : int,
                                    pktRcvLoss : int,
                                    pktRcvLossTotal : int,
                                    pktRcvRetrans : int,
                                    pktRcvUndecrypt : int,
                                    pktRcvUndecryptTotal : int,
                                    pktRecv : int,
                                    pktRecvACK : int,
                                    pktRecvACKTotal : int,
                                    pktRecvNAK : int,
                                    pktRecvNAKTotal : int,
                                    pktRecvTotal : int,
                                    pktReorderDistance : int,
                                    pktRetrans : int,
                                    pktRetransTotal : int,
                                    pktSent : int,
                                    pktSentACK : int,
                                    pktSentACKTotal : int,
                                    pktSentNAK : int,
                                    pktSentNAKTotal : int,
                                    pktSentTotal : int,
                                    pktSndBuf : int,
                                    pktSndDrop : int,
                                    pktSndDropTotal : int,
                                    pktSndFilterExtra : int,
                                    pktSndFilterExtraTotal : int,
                                    pktSndLoss : int,
                                    pktSndLossTotal : int,
                                    usPktSndPeriod : float,
                                    usSndDuration : int,
                                    usSndDurationTotal : int},
                        bstats : (?clear : bool?) -> 
                                 {
                                   byteAvailRcvBuf : int,
                                   byteAvailSndBuf : int,
                                   byteMSS : int,
                                   byteRcvBuf : int,
                                   byteRcvDrop : int,
                                   byteRcvDropTotal : int,
                                   byteRcvUndecrypt : int,
                                   byteRcvUndecryptTotal : int,
                                   byteRecv : int,
                                   byteRecvTotal : int,
                                   byteRetrans : int,
                                   byteRetransTotal : int,
                                   byteSent : int,
                                   byteSentTotal : int,
                                   byteSndBuf : int,
                                   byteSndDrop : int,
                                   byteSndDropTotal : int,
                                   mbpsBandwidth : float,
                                   mbpsMaxBW : float,
                                   mbpsRecvRate : float,
                                   mbpsSendRate : float,
                                   msRTT : float,
                                   msRcvBuf : int,
                                   msRcvTsbPdDelay : int,
                                   msSndBuf : int,
                                   msSndTsbPdDelay : int,
                                   msTimeStamp : int,
                                   pktCongestionWindow : int,
                                   pktFlightSize : int,
                                   pktFlowWindow : int,
                                   pktRcvAvgBelatedTime : float,
                                   pktRcvBelated : int,
                                   pktRcvBuf : int,
                                   pktRcvDrop : int,
                                   pktRcvDropTotal : int,
                                   pktRcvFilterExtra : int,
                                   pktRcvFilterExtraTotal : int,
                                   pktRcvFilterLoss : int,
                                   pktRcvFilterLossTotal : int,
                                   pktRcvFilterSupply : int,
                                   pktRcvFilterSupplyTotal : int,
                                   pktRcvLoss : int,
                                   pktRcvLossTotal : int,
                                   pktRcvRetrans : int,
                                   pktRcvUndecrypt : int,
                                   pktRcvUndecryptTotal : int,
                                   pktRecv : int,
                                   pktRecvACK : int,
                                   pktRecvACKTotal : int,
                                   pktRecvNAK : int,
                                   pktRecvNAKTotal : int,
                                   pktRecvTotal : int,
                                   pktReorderDistance : int,
                                   pktRetrans : int,
                                   pktRetransTotal : int,
                                   pktSent : int,
                                   pktSentACK : int,
                                   pktSentACKTotal : int,
                                   pktSentNAK : int,
                                   pktSentNAKTotal : int,
                                   pktSentTotal : int,
                                   pktSndBuf : int,
                                   pktSndDrop : int,
                                   pktSndDropTotal : int,
                                   pktSndFilterExtra : int,
                                   pktSndFilterExtraTotal : int,
                                   pktSndLoss : int,
                                   pktSndLossTotal : int,
                                   usPktSndPeriod : float,
                                   usSndDuration : int,
                                   usSndDurationTotal : int},
                        close : () -> unit,
                        pbkeylen : () -> int,
                        read_data : () -> int,
                        read_latency : () -> int,
                        read_timeout : () -> int,
                        status : () -> string,
                        streamid : () -> string,
                        write_timeout : () -> int
                      }) -> bool)?,
 ?max_clients : int?, ?messageapi : bool, ?mode : string,
 ?on_connect : (() -> unit), ?on_disconnect : (() -> unit),
 ?on_start : (() -> unit), ?on_stop : (() -> unit), ?passphrase : string?,
 ?payload_size : int, ?pbkeylen : int?, ?polling_delay : float, ?port : int,
 ?read_timeout : float?, ?start : bool, ?streamid : string?,
 ?write_timeout : float?, format('a), source('a)) -> unit

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
bind_address (of type string, which defaults to "0.0.0.0"): Address to bind on the local machine. Used only in listener mode
connection_timeout (of type float?, which defaults to null): Timeout, in seconds, after which initial connection operations are aborted if no data was received. Uses library’s default if nulll. Used only in client mode.
enforced_encryption (of type bool?, which defaults to null): Enforces that both connection parties have the same passphrase set, or both do not set the passphrase, otherwise the connection is rejected.
fallible (of type bool, which defaults to false): Allow the child source to fail, in which case the output will be stopped until the source is available again.
host (of type string, which defaults to "localhost"): Address to connect to. Used only in caller mode.
listen_callback (of type ((hs_version : int, peeraddr : string, streamid : string?, srt_socket .{ bistats : (?clear : bool?, ?instantaneous : bool?) -> { byteAvailRcvBuf : int, byteAvailSndBuf : int, byteMSS : int, byteRcvBuf : int, byteRcvDrop : int, byteRcvDropTotal : int, byteRcvUndecrypt : int, byteRcvUndecryptTotal : int, byteRecv : int, byteRecvTotal : int, byteRetrans : int, byteRetransTotal : int, byteSent : int, byteSentTotal : int, byteSndBuf : int, byteSndDrop : int, byteSndDropTotal : int, mbpsBandwidth : float, mbpsMaxBW : float, mbpsRecvRate : float, mbpsSendRate : float, msRTT : float, msRcvBuf : int, msRcvTsbPdDelay : int, msSndBuf : int, msSndTsbPdDelay : int, msTimeStamp : int, pktCongestionWindow : int, pktFlightSize : int, pktFlowWindow : int, pktRcvAvgBelatedTime : float, pktRcvBelated : int, pktRcvBuf : int, pktRcvDrop : int, pktRcvDropTotal : int, pktRcvFilterExtra : int, pktRcvFilterExtraTotal : int, pktRcvFilterLoss : int, pktRcvFilterLossTotal : int, pktRcvFilterSupply : int, pktRcvFilterSupplyTotal : int, pktRcvLoss : int, pktRcvLossTotal : int, pktRcvRetrans : int, pktRcvUndecrypt : int, pktRcvUndecryptTotal : int, pktRecv : int, pktRecvACK : int, pktRecvACKTotal : int, pktRecvNAK : int, pktRecvNAKTotal : int, pktRecvTotal : int, pktReorderDistance : int, pktRetrans : int, pktRetransTotal : int, pktSent : int, pktSentACK : int, pktSentACKTotal : int, pktSentNAK : int, pktSentNAKTotal : int, pktSentTotal : int, pktSndBuf : int, pktSndDrop : int, pktSndDropTotal : int, pktSndFilterExtra : int, pktSndFilterExtraTotal : int, pktSndLoss : int, pktSndLossTotal : int, usPktSndPeriod : float, usSndDuration : int, usSndDurationTotal : int}, bstats : (?clear : bool?) -> { byteAvailRcvBuf : int, byteAvailSndBuf : int, byteMSS : int, byteRcvBuf : int, byteRcvDrop : int, byteRcvDropTotal : int, byteRcvUndecrypt : int, byteRcvUndecryptTotal : int, byteRecv : int, byteRecvTotal : int, byteRetrans : int, byteRetransTotal : int, byteSent : int, byteSentTotal : int, byteSndBuf : int, byteSndDrop : int, byteSndDropTotal : int, mbpsBandwidth : float, mbpsMaxBW : float, mbpsRecvRate : float, mbpsSendRate : float, msRTT : float, msRcvBuf : int, msRcvTsbPdDelay : int, msSndBuf : int, msSndTsbPdDelay : int, msTimeStamp : int, pktCongestionWindow : int, pktFlightSize : int, pktFlowWindow : int, pktRcvAvgBelatedTime : float, pktRcvBelated : int, pktRcvBuf : int, pktRcvDrop : int, pktRcvDropTotal : int, pktRcvFilterExtra : int, pktRcvFilterExtraTotal : int, pktRcvFilterLoss : int, pktRcvFilterLossTotal : int, pktRcvFilterSupply : int, pktRcvFilterSupplyTotal : int, pktRcvLoss : int, pktRcvLossTotal : int, pktRcvRetrans : int, pktRcvUndecrypt : int, pktRcvUndecryptTotal : int, pktRecv : int, pktRecvACK : int, pktRecvACKTotal : int, pktRecvNAK : int, pktRecvNAKTotal : int, pktRecvTotal : int, pktReorderDistance : int, pktRetrans : int, pktRetransTotal : int, pktSent : int, pktSentACK : int, pktSentACKTotal : int, pktSentNAK : int, pktSentNAKTotal : int, pktSentTotal : int, pktSndBuf : int, pktSndDrop : int, pktSndDropTotal : int, pktSndFilterExtra : int, pktSndFilterExtraTotal : int, pktSndLoss : int, pktSndLossTotal : int, usPktSndPeriod : float, usSndDuration : int, usSndDurationTotal : int}, close : () -> unit, pbkeylen : () -> int, read_data : () -> int, read_latency : () -> int, read_timeout : () -> int, status : () -> string, streamid : () -> string, write_timeout : () -> int }) -> bool)?, which defaults to null): Callback used to decide whether to accept new incoming connections. Used in listener mode only.
max_clients (of type int?, which defaults to null): Max number of connected clients (listener mode only)
messageapi (of type bool, which defaults to true): Use message api
mode (of type string, which defaults to "caller"): Mode to operate on. One of: "listener" (waits for connection to come in) or "caller" (initiate connection to a remote server)
on_connect (of type () -> unit, which defaults to {()}): Function to execute when connected.
on_disconnect (of type () -> unit, which defaults to {()}): Function to execute when disconnected
on_start (of type () -> unit, which defaults to {()}): Callback executed when output starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when output stops.
passphrase (of type string?, which defaults to null): When set to a non-empty string, this option enables encryption and sets the passphrase for it. See libsrt documentation for more details.
payload_size (of type int, which defaults to 1316): Payload size.
pbkeylen (of type int?, which defaults to null): Set encryption key length. See libsrt documentation for more details.
polling_delay (of type float, which defaults to 2.): Delay between connection attempts. Used only in caller mode.
port (of type int, which defaults to 8000): Port to bind on the local machine (listener mode) or to connect to (caller mode). The term port as used in SRT is occasionally identical to the term UDP port. However SRT offers more flexibility than UDP because it manages ports as its own resources. For example, one port may be shared between various services.
read_timeout (of type float?, which defaults to 1.): Timeout, in seconds, after which read operations are aborted if no data was received, indefinite if null.
start (of type bool, which defaults to true): Start output as soon as it is available.
streamid (of type string?, which defaults to null): Set streamid. This value can be retrieved by the listener side when connecting to it. Used in caller mode only.
write_timeout (of type float?, which defaults to 1.): Timeout, in seconds, after which write operations are aborted if no data was received, indefinite if null.
(unlabeled) (of type format('a)): Encoding format.
(unlabeled) (of type source('a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
sockets (of type () -> [string * srt_socket .{ bistats : (?clear : bool?, ?instantaneous : bool?) -> { byteAvailRcvBuf : int, byteAvailSndBuf : int, byteMSS : int, byteRcvBuf : int, byteRcvDrop : int, byteRcvDropTotal : int, byteRcvUndecrypt : int, byteRcvUndecryptTotal : int, byteRecv : int, byteRecvTotal : int, byteRetrans : int, byteRetransTotal : int, byteSent : int, byteSentTotal : int, byteSndBuf : int, byteSndDrop : int, byteSndDropTotal : int, mbpsBandwidth : float, mbpsMaxBW : float, mbpsRecvRate : float, mbpsSendRate : float, msRTT : float, msRcvBuf : int, msRcvTsbPdDelay : int, msSndBuf : int, msSndTsbPdDelay : int, msTimeStamp : int, pktCongestionWindow : int, pktFlightSize : int, pktFlowWindow : int, pktRcvAvgBelatedTime : float, pktRcvBelated : int, pktRcvBuf : int, pktRcvDrop : int, pktRcvDropTotal : int, pktRcvFilterExtra : int, pktRcvFilterExtraTotal : int, pktRcvFilterLoss : int, pktRcvFilterLossTotal : int, pktRcvFilterSupply : int, pktRcvFilterSupplyTotal : int, pktRcvLoss : int, pktRcvLossTotal : int, pktRcvRetrans : int, pktRcvUndecrypt : int, pktRcvUndecryptTotal : int, pktRecv : int, pktRecvACK : int, pktRecvACKTotal : int, pktRecvNAK : int, pktRecvNAKTotal : int, pktRecvTotal : int, pktReorderDistance : int, pktRetrans : int, pktRetransTotal : int, pktSent : int, pktSentACK : int, pktSentACKTotal : int, pktSentNAK : int, pktSentNAKTotal : int, pktSentTotal : int, pktSndBuf : int, pktSndDrop : int, pktSndDropTotal : int, pktSndFilterExtra : int, pktSndFilterExtraTotal : int, pktSndLoss : int, pktSndLossTotal : int, usPktSndPeriod : float, usSndDuration : int, usSndDurationTotal : int}, bstats : (?clear : bool?) -> { byteAvailRcvBuf : int, byteAvailSndBuf : int, byteMSS : int, byteRcvBuf : int, byteRcvDrop : int, byteRcvDropTotal : int, byteRcvUndecrypt : int, byteRcvUndecryptTotal : int, byteRecv : int, byteRecvTotal : int, byteRetrans : int, byteRetransTotal : int, byteSent : int, byteSentTotal : int, byteSndBuf : int, byteSndDrop : int, byteSndDropTotal : int, mbpsBandwidth : float, mbpsMaxBW : float, mbpsRecvRate : float, mbpsSendRate : float, msRTT : float, msRcvBuf : int, msRcvTsbPdDelay : int, msSndBuf : int, msSndTsbPdDelay : int, msTimeStamp : int, pktCongestionWindow : int, pktFlightSize : int, pktFlowWindow : int, pktRcvAvgBelatedTime : float, pktRcvBelated : int, pktRcvBuf : int, pktRcvDrop : int, pktRcvDropTotal : int, pktRcvFilterExtra : int, pktRcvFilterExtraTotal : int, pktRcvFilterLoss : int, pktRcvFilterLossTotal : int, pktRcvFilterSupply : int, pktRcvFilterSupplyTotal : int, pktRcvLoss : int, pktRcvLossTotal : int, pktRcvRetrans : int, pktRcvUndecrypt : int, pktRcvUndecryptTotal : int, pktRecv : int, pktRecvACK : int, pktRecvACKTotal : int, pktRecvNAK : int, pktRecvNAKTotal : int, pktRecvTotal : int, pktReorderDistance : int, pktRetrans : int, pktRetransTotal : int, pktSent : int, pktSentACK : int, pktSentACKTotal : int, pktSentNAK : int, pktSentNAKTotal : int, pktSentTotal : int, pktSndBuf : int, pktSndDrop : int, pktSndDropTotal : int, pktSndFilterExtra : int, pktSndFilterExtraTotal : int, pktSndLoss : int, pktSndLossTotal : int, usPktSndPeriod : float, usSndDuration : int, usSndDurationTotal : int}, close : () -> unit, pbkeylen : () -> int, read_data : () -> int, read_latency : () -> int, read_timeout : () -> int, status : () -> string, streamid : () -> string, write_timeout : () -> int }]): List of (connected_address, connected_socket)
start (of type () -> unit): Ask the source or output to start.
stop (of type () -> unit): Ask the source or output to stop.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`output.url`

Encode and let encoder handle data output. Useful with encoder with no expected output or to encode to files that need full control from the encoder, e.g. %ffmpeg with rtmp output.

Type:

(?id : string?, ?fallible : bool,
 ?on_error : ((error
               .{
                 kind : string,
                 message : string,
                 trace : [
                          {
                            position_end : 
                            {
                              character_offset : int,
                              filename : string,
                              line_number : int
                            },
                            position_start : 
                            {
                              character_offset : int,
                              filename : string,
                              line_number : int
                            },
                            to_string : (?prefix : string) -> string
                          }]
               }) -> unit),
 ?on_start : (() -> unit), ?on_stop : (() -> unit), ?restart_delay : float?,
 ?self_sync : bool, ?start : bool, url : string, format('a), source('a)) ->
unit

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
fallible (of type bool, which defaults to false): Allow the child source to fail, in which case the output will be stopped until the source is available again.
on_error (of type (error .{ kind : string, message : string, trace : [ { position_end : {character_offset : int, filename : string, line_number : int }, position_start : {character_offset : int, filename : string, line_number : int }, to_string : (?prefix : string) -> string }] }) -> unit, which defaults to <fun>): Callback executed when an error occurs.
on_start (of type () -> unit, which defaults to {()}): Callback executed when output starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when output stops.
restart_delay (of type float?, which defaults to 2.): If not null, restart output on errors after the given delay.
self_sync (of type bool, which defaults to false): Should the source control its own synchronization? Set to true for output to e.g. rtmp output using %ffmpeg and etc.
start (of type bool, which defaults to true): Start output as soon as it is available.
url (of type string): Url to output to.
(unlabeled) (of type format('a)): Encoding format.
(unlabeled) (of type source('a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
stop (of type () -> unit): Ask the source or output to stop.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`output.video`

Output a video stream using the default operator. The input source does not need to be infallible, blank will just be played during failures.

Type:

(?id : string?, ?fallible : bool, ?on_start : (() -> unit),
 ?on_stop : (() -> unit), ?start : bool, source(video=canvas('a), 'b)) ->
unit

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
fallible (of type bool, which defaults to true): Allow the child source to fail, in which case the output will be (temporarily) stopped.
on_start (of type () -> unit, which defaults to {()}): Callback executed when outputting starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when outputting stops.
start (of type bool, which defaults to true): Automatically start outputting whenever possible. If true, an infallible (normal) output will start outputting as soon as it is created, and a fallible output will (re)start as soon as its source becomes available for streaming.
(unlabeled) (of type source(video=canvas('a), 'b)): Source to play.

`output.youtube.live.hls`

Stream to youtube using HLS.

Type:

(?id : string?, ?fallible : bool, ?on_start : (() -> unit),
 ?on_stop : (() -> unit), ?segment_duration : float, ?segments : int,
 ?segments_overhead : int, ?start : bool, ?url : string, key : string,
 encoder : format('a)
 .{
   bandwidth? : int,
   codecs? : string,
   extname? : string,
   extra_tags? : [string],
   id3? : bool,
   id3_version? : int,
   replay_id3? : bool,
   video_size? : int * int
 }, source('a)) -> unit

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
fallible (of type bool, which defaults to false): Allow the child source to fail, in which case the output will be (temporarily) stopped.
on_start (of type () -> unit, which defaults to {()}): Callback executed when outputting starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when outputting stops.
segment_duration (of type float, which defaults to 2.): Segment duration (in seconds).
segments (of type int, which defaults to 4): Number of segments per playlist.
segments_overhead (of type int, which defaults to 4): Number of segments to keep after they have been featured in the live playlist.
start (of type bool, which defaults to true): Automatically start outputting whenever possible. If true, an infallible (normal) output will start outputting as soon as it is created, and a fallible output will (re)start as soon as its source becomes available for streaming.
url (of type string, which defaults to "https://a.upload.youtube.com/http_upload_hls"): HLS URL to stream to
key (of type string): Your secret youtube key
encoder (of type format('a) .{ bandwidth? : int, codecs? : string, extname? : string, extra_tags? : [string], id3? : bool, id3_version? : int, replay_id3? : bool, video_size? : int * int }): Encoder to use (most likely a %ffmpeg encoder)
(unlabeled) (of type source('a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
stop (of type () -> unit): Ask the source or output to stop.
streams (of type () -> [ { bandwidth : int, codecs : string, discontinuity_count : int, encoder : format('A), extname : string, extra_tags : [string], id3_enabled : bool, insert_tag : (string) -> unit, name : string, replay_id3 : bool, video_size : {height : int, width : int }? }]): Output streams
time (of type () -> float): Get a source’s time, based on its assigned clock.

`output.youtube.live.rtmp`

Stream to youtube using RTMP.

Type:

(?id : string?, ?fallible : bool, ?on_start : (() -> unit),
 ?on_stop : (() -> unit), ?start : bool, ?url : string, key : string,
 encoder : format('a), source('a)) -> unit

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
fallible (of type bool, which defaults to false): Allow the child source to fail, in which case the output will be (temporarily) stopped.
on_start (of type () -> unit, which defaults to {()}): Callback executed when outputting starts.
on_stop (of type () -> unit, which defaults to {()}): Callback executed when outputting stops.
start (of type bool, which defaults to true): Automatically start outputting whenever possible. If true, an infallible (normal) output will start outputting as soon as it is created, and a fallible output will (re)start as soon as its source becomes available for streaming.
url (of type string, which defaults to "rtmp://a.rtmp.youtube.com/live2"): RTMP URL to stream to
key (of type string): Your secret youtube key
encoder (of type format('a)): Encoder to use (most likely a %ffmpeg encoder)
(unlabeled) (of type source('a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_started (of type () -> bool): true if the output or source is started.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
shutdown (of type () -> unit): Shutdown the output or source.
skip (of type () -> unit): Skip to the next track.
start (of type () -> unit): Ask the source or output to start.
stop (of type () -> unit): Ask the source or output to stop.
time (of type () -> float): Get a source’s time, based on its assigned clock.

Source / Sound synthesis

`dssi.register`

Type:

(string) -> unit

Arguments:

(unlabeled) (of type string): Path of the DSSI plugin file.

`synth.all.saw`

Saw synthesizer. It creates one synthesizer for each channel.

Type:

(?id : string?, ?attack : float, ?decay : float, ?envelope : bool,
 ?release : float, ?sustain : float, source(midi=midi(channels=16), 'a)) ->
source(midi=midi(channels=16), 'a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
attack (of type float, which defaults to 0.02): Envelope attack (in seconds).
decay (of type float, which defaults to 0.01): Envelope decay (in seconds).
envelope (of type bool, which defaults to true): Use envelope.
release (of type float, which defaults to 0.01): Envelope release (in seconds).
sustain (of type float, which defaults to 0.9): Envelope sustain level.
(unlabeled) (of type source(midi=midi(channels=16), 'a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`synth.all.sine`

Sine synthesizer. It creates one synthesizer for each channel.

Type:

(?id : string?, ?attack : float, ?decay : float, ?envelope : bool,
 ?release : float, ?sustain : float, source(midi=midi(channels=16), 'a)) ->
source(midi=midi(channels=16), 'a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
attack (of type float, which defaults to 0.02): Envelope attack (in seconds).
decay (of type float, which defaults to 0.01): Envelope decay (in seconds).
envelope (of type bool, which defaults to true): Use envelope.
release (of type float, which defaults to 0.01): Envelope release (in seconds).
sustain (of type float, which defaults to 0.9): Envelope sustain level.
(unlabeled) (of type source(midi=midi(channels=16), 'a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`synth.all.square`

Square synthesizer. It creates one synthesizer for each channel.

Type:

(?id : string?, ?attack : float, ?decay : float, ?envelope : bool,
 ?release : float, ?sustain : float, source(midi=midi(channels=16), 'a)) ->
source(midi=midi(channels=16), 'a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
attack (of type float, which defaults to 0.02): Envelope attack (in seconds).
decay (of type float, which defaults to 0.01): Envelope decay (in seconds).
envelope (of type bool, which defaults to true): Use envelope.
release (of type float, which defaults to 0.01): Envelope release (in seconds).
sustain (of type float, which defaults to 0.9): Envelope sustain level.
(unlabeled) (of type source(midi=midi(channels=16), 'a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`synth.saw`

Saw synthesizer.

Type:

(?id : string?, ?attack : float, ?channel : int, ?decay : float,
 ?envelope : bool, ?release : float, ?sustain : float, ?volume : float,
 source(midi=midi(channels=1), 'a)) -> source(midi=midi(channels=1), 'a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
attack (of type float, which defaults to 0.02): Envelope attack (in seconds).
channel (of type int, which defaults to 0): MIDI channel to handle.
decay (of type float, which defaults to 0.01): Envelope decay (in seconds).
envelope (of type bool, which defaults to true): Use envelope.
release (of type float, which defaults to 0.05): Envelope release (in seconds).
sustain (of type float, which defaults to 0.9): Envelope sustain level.
volume (of type float, which defaults to 0.3): Initial volume.
(unlabeled) (of type source(midi=midi(channels=1), 'a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`synth.sine`

Sine synthesizer.

Type:

(?id : string?, ?attack : float, ?channel : int, ?decay : float,
 ?envelope : bool, ?release : float, ?sustain : float, ?volume : float,
 source(midi=midi(channels=1), 'a)) -> source(midi=midi(channels=1), 'a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
attack (of type float, which defaults to 0.02): Envelope attack (in seconds).
channel (of type int, which defaults to 0): MIDI channel to handle.
decay (of type float, which defaults to 0.01): Envelope decay (in seconds).
envelope (of type bool, which defaults to true): Use envelope.
release (of type float, which defaults to 0.05): Envelope release (in seconds).
sustain (of type float, which defaults to 0.9): Envelope sustain level.
volume (of type float, which defaults to 0.3): Initial volume.
(unlabeled) (of type source(midi=midi(channels=1), 'a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`synth.square`

Square synthesizer.

Type:

(?id : string?, ?attack : float, ?channel : int, ?decay : float,
 ?envelope : bool, ?release : float, ?sustain : float, ?volume : float,
 source(midi=midi(channels=1), 'a)) -> source(midi=midi(channels=1), 'a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
attack (of type float, which defaults to 0.02): Envelope attack (in seconds).
channel (of type int, which defaults to 0): MIDI channel to handle.
decay (of type float, which defaults to 0.01): Envelope decay (in seconds).
envelope (of type bool, which defaults to true): Use envelope.
release (of type float, which defaults to 0.05): Envelope release (in seconds).
sustain (of type float, which defaults to 0.9): Envelope sustain level.
volume (of type float, which defaults to 0.3): Initial volume.
(unlabeled) (of type source(midi=midi(channels=1), 'a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

Source / Testing

`sleeper`

Sleep regularly, thus inducing delays in the sound production. This is mainly useful for emulating network delays or sources which are slow to produce data, and thus test bufferization and robustness of scripts.

Type:

(?every : float, ?delay : float, ?delay_random : float,
 ?on_delay : ((float) -> unit), source('a)) -> source('a)

Arguments:

every (of type float, which defaults to 1.): How often we should sleep (in seconds, 0 means every frame).
delay (of type float, which defaults to 1.1): Delay introduced (in seconds).
delay_random (of type float, which defaults to 0.): Maximum amount of time randomly added to the delay (in seconds).
on_delay (of type (float) -> unit, which defaults to fun (_) -> ()): Function called when a delay is introduced, with the delay as argument.
(unlabeled) (of type source('a)): Source in which the delays should be introduced.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
frozen (of type (() -> bool).{set : (bool) -> unit}): The stream production is frozen while set to true.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

This function is experimental.

Source / Track processing

`append`

Append an extra track to every track. Set the metadata ‘liq_append’ to ‘false’ to inhibit appending on one track.

Type:

(?id : string?, ?insert_missing : bool, ?merge : bool, source('a),
 (([string * string]) -> source('a))) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
insert_missing (of type bool, which defaults to true): Treat track beginnings without metadata as having empty one.
merge (of type bool, which defaults to false): Merge the track with its appended track.
(unlabeled) (of type source('a))
(unlabeled) (of type ([string * string]) -> source('a)): Given the metadata, build the source producing the track to append. This source is allowed to fail (produce nothing) if no relevant track is to be appended.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
cancel_pending (of type () -> unit): Cancel any pending appended source.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type (?cancel_pending : bool) -> unit): Skip the current track. Pending appended source are cancelled by default. Pass cancel_pending=false to keep it.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`blank.detect`

Calls a given handler when detecting a blank.

Type:

(?id : string?, ?max_blank : float, ?min_noise : float,
 ?on_noise : (() -> unit), ?start_blank : bool, ?threshold : float,
 ?track_sensitive : bool, (() -> unit), source(audio=pcm('a), 'b)) ->
source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
max_blank (of type float, which defaults to 20.): Maximum duration of silence allowed, in seconds.
min_noise (of type float, which defaults to 0.): Minimum duration of noise required to end silence, in seconds.
on_noise (of type () -> unit, which defaults to {()}): Handler called when noise is detected.
start_blank (of type bool, which defaults to false): Start assuming we have blank.
threshold (of type float, which defaults to -40.): Power in decibels under which the stream is considered silent.
track_sensitive (of type bool, which defaults to true): Reset blank counter at each track.
(unlabeled) (of type () -> unit): Handler called when blank is detected.
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_blank (of type () -> bool): Indicate whether blank was detected.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`blank.eat`

Eat blanks, i.e., drop the contents of the stream until it is not blank anymore.

Type:

(?id : string?, ?at_beginning : bool, ?max_blank : float, ?min_noise : float,
 ?start_blank : bool, ?threshold : float, ?track_sensitive : bool,
 source(audio=pcm('a), 'b)) -> source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
at_beginning (of type bool, which defaults to false): Only eat at the beginning of a track.
max_blank (of type float, which defaults to 20.): Maximum duration of silence allowed, in seconds.
min_noise (of type float, which defaults to 0.): Minimum duration of noise required to end silence, in seconds.
start_blank (of type bool, which defaults to false): Start assuming we have blank.
threshold (of type float, which defaults to -40.): Power in decibels under which the stream is considered silent.
track_sensitive (of type bool, which defaults to true): Reset blank counter at each track.
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_blank (of type () -> bool): Indicate whether blank was detected.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`blank.skip`

Skip track when detecting a blank.

Type:

(?id : string?, ?threshold : float, ?max_blank : float, ?min_noise : float,
 ?track_sensitive : bool, source(audio=pcm('a), 'b).{skip : () -> unit}) ->
source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to "blank.skip"): Force the value of the source ID.
threshold (of type float, which defaults to -40.): Power in decibels under which the stream is considered silent.
max_blank (of type float, which defaults to 20.): Maximum silence length allowed, in seconds.
min_noise (of type float, which defaults to 0.): Minimum duration of noise required to end silence, in seconds.
track_sensitive (of type bool, which defaults to true): Reset blank counter at each track.
(unlabeled) (of type source(audio=pcm('a), 'b).{skip : () -> unit})

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_blank (of type () -> bool): Indicate whether blank was detected.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`blank.strip`

Make the source unavailable when it is streaming blank.

Type:

(?id : string?, ?max_blank : float, ?min_noise : float, ?start_blank : bool,
 ?threshold : float, ?track_sensitive : bool, source(audio=pcm('a), 'b)) ->
source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
max_blank (of type float, which defaults to 20.): Maximum duration of silence allowed, in seconds.
min_noise (of type float, which defaults to 0.): Minimum duration of noise required to end silence, in seconds.
start_blank (of type bool, which defaults to false): Start assuming we have blank.
threshold (of type float, which defaults to -40.): Power in decibels under which the stream is considered silent.
track_sensitive (of type bool, which defaults to true): Reset blank counter at each track.
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_blank (of type () -> bool): Indicate whether blank was detected.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`cue_cut`

Start track after a cue in point and stop it at cue out point. The cue points are given as metadata, in seconds from the beginning of tracks.

Type:

(?id : string?, ?cue_in_metadata : string, ?cue_out_metadata : string,
 ?on_cue_in : (() -> unit), ?on_cue_out : (() -> unit), source('a)) ->
source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
cue_in_metadata (of type string, which defaults to "liq_cue_in"): Metadata for cue in points.
cue_out_metadata (of type string, which defaults to "liq_cue_out"): Metadata for cue out points.
on_cue_in (of type () -> unit, which defaults to {()}): Callback to execute on cue in
on_cue_out (of type () -> unit, which defaults to {()}): Callback to execute on cue out
(unlabeled) (of type source('a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`delay`

Make the source unavailable for a given time between tracks.

Type:

(?id : string?, ?initial : bool, {float}, source('a)) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
initial (of type bool, which defaults to false): Start in unavailable state, as if a track had just finished.
(unlabeled) (of type {float}): The source won’t be ready less than this amount of seconds after any end of track
(unlabeled) (of type source('a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`fallback`

At the beginning of each track, select the first ready child.

Type:

(?id : string?, ?override : string, ?replay_metadata : bool,
 ?track_sensitive : bool, ?transition_length : float,
 ?transitions : [(source('a), source('a)) -> source('a)], [source('a)]) ->
source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
override (of type string, which defaults to "liq_transition_length"): Metadata field which, if present and containing a float, overrides the transition_length parameter.
replay_metadata (of type bool, which defaults to true): Replay the last metadata of a child when switching to it in the middle of a track.
track_sensitive (of type bool, which defaults to true): Re-select only on end of tracks.
transition_length (of type float, which defaults to 5.): Maximum transition duration.
transitions (of type [(source('a), source('a)) -> source('a)], which defaults to []): Transition functions, padded with fun (x,y) -> y functions.
(unlabeled) (of type [source('a)])

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
selected (of type () -> source('A)?): Currently selected source.
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`insert_metadata`

Dynamically insert metadata in a stream. Returns the source decorated with a method insert_metadata which is a function of type (?new_track,metadata)->unit, used to insert metadata in the source. This function also inserts a new track with the given metadata if passed new_track=true.

Type:

(?id : string?, source('a)) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
(unlabeled) (of type source('a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
insert_metadata (of type (?new_track : bool, [string * string]) -> unit): Insert metadata in the source. The new_track parameter indicates whether a track boundary should also be inserted (by default, no track is inserted).
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`max_duration`

Limit source duration

Type:

(?id : string?, ?override : string, float, source('a)) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
override (of type string, which defaults to "liq_remaining"): Metadata field which, if present and containing a float, overrides the remaining play time.
(unlabeled) (of type float): Maximum duration
(unlabeled) (of type source('a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`metadata.map`

Rewrite metadata on the fly using a function.

Type:

(?id : string?, ?update : bool, ?strip : bool, ?insert_missing : bool,
 (([string * string]) -> [string * string]), source('a)) -> source('a)
where 'a is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to "metadata.map"): Force the value of the track ID.
update (of type bool, which defaults to true): Update metadata. If false, existing metadata are cleared and only returned values are set as new metadata.
strip (of type bool, which defaults to false): Completely remove empty metadata. Operates on both empty values and empty metadata chunk.
insert_missing (of type bool, which defaults to true): Treat track beginnings without metadata as having empty ones. The operational order is: create empty if needed, map and strip if enabled.
(unlabeled) (of type ([string * string]) -> [string * string])
(unlabeled) (of type source('a) where 'a is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`mksafe`

Turn a source into an infaillible source by adding blank when the source is not available.

Type:

(?id : string, source('a)) -> source('a) where 'a is a set of internal tracks

Arguments:

id (of type string, which defaults to "mksafe")
(unlabeled) (of type source('a) where 'a is a set of internal tracks): the source to turn infaillible

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
selected (of type () -> source('A)? where 'A is a set of internal tracks): Currently selected source.
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`on_offset`

Call a given handler when position in track is equal or more than a given amount of time.

Type:

(?id : string?, ?force : bool, ?offset : float, ?override : string,
 ((float, [string * string]) -> unit), source('a)) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
force (of type bool, which defaults to false): Force execution of callback if track ends before ‘offset’ position has been reached.
offset (of type float, which defaults to -1.): Execute handler when position in track is equal or more than to this value.
override (of type string, which defaults to "liq_on_offset"): Metadata field which, if present and containing a float, overrides the ‘offset’ parameter.
(unlabeled) (of type (float, [string * string]) -> unit): Function to execute. First argument is the actual position within the current track, second is the latest metadata. That function should be fast because it is executed in the main streaming thread.
(unlabeled) (of type source('a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`once`

Creates a source that plays only one track of the input source.

Type:

(?id : string?, source('a)) -> source('a)

Arguments:

id (of type string?, which defaults to "once")
(unlabeled) (of type source('a)): The input source.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`prepend`

Prepend an extra track before every track. Set the metadata ‘liq_prepend’ to ‘false’ to inhibit prepending on one track.

Type:

(?id : string?, ?merge : bool, source('a),
 (([string * string]) -> source('a))) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
merge (of type bool, which defaults to false): Merge the track with its appended track.
(unlabeled) (of type source('a))
(unlabeled) (of type ([string * string]) -> source('a)): Given the metadata, build the source producing the track to prepend. This source is allowed to fail (produce nothing) if no relevant track is to be appended. However, success must be immediate or it will not be taken into account.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`random`

At the beginning of every track, select a random ready child.

Type:

(?id : string?, ?override : string, ?replay_metadata : bool,
 ?transition_length : float,
 ?transitions : [(source('a), source('a)) -> source('a)], ?weights : 
 [{int}], [source('a)]) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
override (of type string, which defaults to "liq_transition_length"): Metadata field which, if present and containing a float, overrides the transition_length parameter.
replay_metadata (of type bool, which defaults to true): Replay the last metadata of a child when switching to it in the middle of a track.
transition_length (of type float, which defaults to 5.): Maximum transition duration.
transitions (of type [(source('a), source('a)) -> source('a)], which defaults to []): Transition functions, padded with fun (x,y) -> y functions.
weights (of type [{int}], which defaults to []): Weights of the children (padded with 1), defining for each child the probability that it is selected.
(unlabeled) (of type [source('a)])

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
selected (of type () -> source('A)?): Currently selected source.
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`request.player`

Create a source on which plays immediately requests given with the play method.

Type:

(?simultaneous : bool) -> source('a) where 'a is a set of internal tracks

Arguments:

simultaneous (of type bool, which defaults to true): Allow multiple requests to play simultaneously. If false a new request replaces the previous one.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
length (of type () -> int): Number of currently playing requests.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
play (of type (request) -> unit): Play a request.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
set (of type (source('A)) -> unit where 'A is a set of internal tracks): Set the source.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`request.queue`

Play a queue of requests (the first added request gets played first).

Type:

(?id : string?, ?interactive : bool, ?prefetch : int, ?native : bool,
 ?queue : [request], ?timeout : float) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
interactive (of type bool, which defaults to true): Should the queue be controllable via telnet?
prefetch (of type int, which defaults to 1): How many requests should be queued in advance.
native (of type bool, which defaults to false): Use native implementation, when available.
queue (of type [request], which defaults to []): Initial queue of requests.
timeout (of type float, which defaults to 20.): Timeout (in sec.) for a single download.

Methods:

add (of type (request) -> bool): This method is internal and should not be used. Consider using push instead.
buffered (of type () -> [string * float]): Length of buffered data.
current (of type () -> request?): Get the request currently being played.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
fetch (of type () -> bool): Try feeding the queue with a new request. Returns true if successful. This method can take long to return and should usually be run in a separate thread.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
length (of type () -> int): Length of the queue.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
push (of type ((request) -> unit).{uri : (string) -> unit}): Push a request on the request queue.
queue (of type () -> [request]): Get the requests currently in the queue.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
set_queue (of type ([request]) -> unit):
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`rotate`

Rotate between sources.

Type:

(?id : string?, ?override : string, ?replay_metadata : bool,
 ?transition_length : float,
 ?transitions : [(source('a), source('a)) -> source('a)], ?weights : 
 [{int}], [source('a)]) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
override (of type string, which defaults to "liq_transition_length"): Metadata field which, if present and containing a float, overrides the transition_length parameter.
replay_metadata (of type bool, which defaults to true): Replay the last metadata of a child when switching to it in the middle of a track.
transition_length (of type float, which defaults to 5.): Maximum transition duration.
transitions (of type [(source('a), source('a)) -> source('a)], which defaults to []): Transition functions, padded with fun (x,y) -> y functions.
weights (of type [{int}], which defaults to []): Weights of the children (padded with 1), defining for each child how many tracks are played from it per round, if that many are actually available.
(unlabeled) (of type [source('a)])

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
selected (of type () -> source('A)?): Currently selected source.
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`sequence`

Play only one track of every successive source, except for the last one which is played as much as available.

Type:

(?id : string?, ?merge : bool, [source('a)]) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
merge (of type bool, which defaults to false): Merge tracks when advancing from one source to the next one. This will NOT merge consecutive tracks from the last source; see merge_tracks() if you need that too.
(unlabeled) (of type [source('a)])

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`source.audio`

Create an audio source from the given track, with metadata and track marks from that same track.

Type:

(?id : string?, 'a) -> source(audio='a) where 'a is a track

Arguments:

id (of type string?, which defaults to "source.audio")
(unlabeled) (of type anything that is a track)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`source.available`

Change the availability of a source depending on a predicate.

Type:

(?id : string?, ?override : bool, ?track_sensitive : {bool}, source('a),
 {bool}) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
override (of type bool, which defaults to false): Don’t take availability of original source in account (this can be dangerous and should be avoided).
track_sensitive (of type {bool}, which defaults to false): Change availability only on end of tracks.
(unlabeled) (of type source('a)): Source of which the availability should be changed.
(unlabeled) (of type {bool}): Predicate indicating whether the source should be available or not.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`source.drop.audio`

Remove the audio track of a source.

Type:

(?id : string?, source(audio='a, 'b)) -> source('b)
where 'b is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to null)
(unlabeled) (of type source(audio='a, 'b) where 'b is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`source.drop.metadata`

Remove the metadata track of a source.

Type:

(?id : string?, source('a)) -> source('a)
where 'a is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to null)
(unlabeled) (of type source('a) where 'a is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`source.drop.midi`

Remove the midi track of a source.

Type:

(?id : string?, source(midi='a, 'b)) -> source('b)
where 'b is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to null)
(unlabeled) (of type source(midi='a, 'b) where 'b is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`source.drop.video`

Remove the video track of a source.

Type:

(?id : string?, source(video='a, 'b)) -> source('b)
where 'b is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to null)
(unlabeled) (of type source(video='a, 'b) where 'b is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`source.dynamic`

Dynamically change the underlying source: it can either be changed by the function given as argument, which returns the source to be played, or by calling the set method.

Type:

(?id : string?, ?infallible : bool, ?init : source('a)?,
 ?resurection_time : float?, ?track_sensitive : bool, ?(() -> source('a)?)) ->
source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
infallible (of type bool, which defaults to false): Whether the source is infallible or not (be careful when setting this, it will not be checked by the typing system).
init (of type source('a)?, which defaults to null): Initial value for the source
resurection_time (of type float?, which defaults to 1.): When track sensitive and the source is unavailable, how long we should wait before trying to update source again (null means never).
track_sensitive (of type bool, which defaults to false): Whether the source should only be updated on track change.
(unlabeled) (of type () -> source('a)?, which defaults to <fun>): Function returning the source to be used, null means keep current source.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
set (of type (source('A)) -> unit): Set the source.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

This function is experimental.

`source.frame.duration`

Compute the duration of the last frame.

Type:

(?id : string?, source('a)) -> source(frame_duration=float, 'a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
(unlabeled) (of type source('a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
frame_duration (of type float): Compute the duration of the last frame.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`source.frame.rms`

Compute the rms of the last frame.

Type:

(?id : string?, source('a)) -> source(frame_rms=float, 'a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
(unlabeled) (of type source('a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
frame_rms (of type float): Compute the rms of the last frame.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`source.mux.audio`

Replace the audio track of a source by the one of another source.

Type:

(?id : string?, audio : source(audio='A, 'B), source('c)) -> source(audio='A,
'c) where 'c is a set of tracks to be muxed into a source, 'A is a track

Arguments:

id (of type string?, which defaults to null)
audio (of type source(audio='B, 'A) where 'B is a track): Source whose audio track is to be taken.
(unlabeled) (of type source('c) where 'c is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`source.mux.midi`

Replace the midi track of a source by the one of another source.

Type:

(?id : string?, midi : source(midi='A, 'B), source('c)) -> source(midi='A,
'c) where 'c is a set of tracks to be muxed into a source, 'A is a track

Arguments:

id (of type string?, which defaults to null)
midi (of type source(midi='B, 'A) where 'B is a track): Source whose midi track is to be taken.
(unlabeled) (of type source('c) where 'c is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`source.mux.track.audio`

Replace the audio track of a source.

Type:

(?id : string?, audio : 'a, source('b)) -> source(audio='a, 'b)
where 'b is a set of tracks to be muxed into a source, 'a is a track

Arguments:

id (of type string?, which defaults to null)
audio (of type anything that is a track)
(unlabeled) (of type source('b) where 'b is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`source.mux.track.video`

Replace the video track of a source.

Type:

(?id : string?, video : 'a, source('b)) -> source(video='a, 'b)
where 'b is a set of tracks to be muxed into a source, 'a is a track

Arguments:

id (of type string?, which defaults to null)
video (of type anything that is a track)
(unlabeled) (of type source('b) where 'b is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`source.mux.video`

Replace the video track of a source by the one of another source.

Type:

(?id : string?, video : source(video='A, 'B), source('c)) -> source(video='A,
'c) where 'c is a set of tracks to be muxed into a source, 'A is a track

Arguments:

id (of type string?, which defaults to null)
video (of type source(video='B, 'A) where 'B is a track)
(unlabeled) (of type source('c) where 'c is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`source.on_end`

Call a given handler when there is less than a given amount of time remaining before then end of track.

Type:

(?id : string?, ?delay : {float}, source('a),
 ((float, [string * string]) -> unit)) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
delay (of type {float}, which defaults to 5.): Execute handler when remaining time is less or equal to this value.
(unlabeled) (of type source('a))
(unlabeled) (of type (float, [string * string]) -> unit): Function to execute. First argument is the remaining time, second is the latest metadata. That function should be fast because it is executed in the main streaming thread.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`source.on_frame`

Call a given handler on every frame.

Type:

(?id : string?, source('a), (() -> unit)) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
(unlabeled) (of type source('a))
(unlabeled) (of type () -> unit): Function called on every frame. It should be fast because it is executed in the main streaming thread.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`source.on_metadata`

Call a given handler on metadata packets.

Type:

(?id : string?, source('a), (([string * string]) -> unit)) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
(unlabeled) (of type source('a))
(unlabeled) (of type ([string * string]) -> unit): Function called on every metadata packet in the stream. It should be fast because it is executed in the main streaming thread.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`source.on_track`

Call a given handler on new tracks.

Type:

(?id : string?, source('a), (([string * string]) -> unit)) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
(unlabeled) (of type source('a))
(unlabeled) (of type ([string * string]) -> unit): Function called on every beginning of track in the stream, with the corresponding metadata as argument. If there is no metadata at the beginning of track, the empty list is passed. That function should be fast because it is executed in the main streaming thread.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`source.run`

Run a function regularly. This is similar to thread.run but based on a source internal time instead of the computer’s time.

Type:

(source('a), ?delay : float, ?every : float?, (() -> unit)) -> source('a)

Arguments:

(unlabeled) (of type source('a)): Source whose time is taken as reference.
delay (of type float, which defaults to 0.): Time to wait before the first run (in seconds).
every (of type float?, which defaults to null): How often to run the function (in seconds). The function is run once if null.
(unlabeled) (of type () -> unit): Function to run.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`source.tracks`

Return the tracks of a given source.

Type:

(source('a)) -> 'a

Arguments:

(unlabeled) (of type source('a))

Methods:

metadata (of type metadata)
track_marks (of type track_marks)

`source.video`

Create a video source from the given track, with metadata and track marks from that same track.

Type:

(?id : string?, 'a) -> source(video='a) where 'a is a track

Arguments:

id (of type string?, which defaults to "source.video")
(unlabeled) (of type anything that is a track)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`switch`

At the beginning of a track, select the first source whose predicate is true.

Type:

(?id : string?, ?all_predicates : bool, ?override : string,
 ?replay_metadata : bool, ?single : [bool], ?track_sensitive : {bool},
 ?transition_length : float,
 ?transitions : [(source('a), source('a)) -> source('a)],
 [(() -> bool) * source('a)]) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
all_predicates (of type bool, which defaults to false): Always evaluate all predicates when re-selecting.
override (of type string, which defaults to "liq_transition_length"): Metadata field which, if present and containing a float, overrides the transition_length parameter.
replay_metadata (of type bool, which defaults to true): Replay the last metadata of a child when switching to it in the middle of a track.
single (of type [bool], which defaults to []): Forbid the selection of a branch for two tracks in a row. The empty list stands for [false,...,false].
track_sensitive (of type {bool}, which defaults to true): Re-select only on end of tracks.
transition_length (of type float, which defaults to 5.): Maximum transition duration.
transitions (of type [(source('a), source('a)) -> source('a)], which defaults to []): Transition functions, padded with fun (x,y) -> y functions.
(unlabeled) (of type [(() -> bool) * source('a)]): Sources with the predicate telling when they can be played.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
selected (of type () -> source('A)?): Currently selected source.
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

Source / Video processing

`image`

Generate a source from a static image.

Type:

(?id : string?, ?fallible : bool, ?width : {int}?, ?height : {int}?,
 ?x : {int}, ?y : {int}, {string}) -> source(video=canvas('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
fallible (of type bool, which defaults to false): Whether we are allowed to fail (in case the file is non-existent or invalid).
width (of type {int}?, which defaults to null): Scale to width
height (of type {int}?, which defaults to null): Scale to height
x (of type {int}, which defaults to 0): x position.
y (of type {int}, which defaults to 0): y position.
(unlabeled) (of type {string}): Path to the image.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
set (of type (string) -> unit): Change the image.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.add_image`

Add a static image on the source video channel.

Type:

(?id : string?, ?width : {int}?, ?height : {int}?, ?x : {int}, ?y : {int},
 file : {string}, source(video=canvas('a), 'b)) -> source(video=canvas('a),
'b) where 'b is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to "video.add_image"): Force the value of the source ID.
width (of type {int}?, which defaults to null): Scale to width
height (of type {int}?, which defaults to null): Scale to height
x (of type {int}, which defaults to 0): x position.
y (of type {int}, which defaults to 0): y position.
file (of type {string}): Path to the image file.
(unlabeled) (of type source(video=canvas('a), 'b) where 'b is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.add_line`

Draw a line on the video.

Type:

(?id : string?, ?alpha : {float}, ?color : {int}, {int * int}, {int * int},
 source(video=canvas('a), 'b)) -> source(video=canvas('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
alpha (of type {float}, which defaults to 1.): Transparency of the color between 0 and 1 (0 is fully transparent and 1 is fully opaque).
color (of type {int}, which defaults to 0): Color to fill the image with (0xRRGGBB).
(unlabeled) (of type {int * int}): Start point.
(unlabeled) (of type {int * int}): End point.
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.add_rectangle`

Draw a rectangle.

Type:

(?id : string?, ?alpha : {float}, ?color : {int}, height : {int},
 width : {int}, ?x : {int}, ?y : {int}, source(video=canvas('a), 'b)) ->
source(video=canvas('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
alpha (of type {float}, which defaults to 1.): Transparency of the color between 0 and 1 (0 is fully transparent and 1 is fully opaque).
color (of type {int}, which defaults to 0): Color to fill the image with (0xRRGGBB).
height (of type {int}): Height.
width (of type {int}): Width.
x (of type {int}, which defaults to 0): Horizontal offset.
y (of type {int}, which defaults to 0): Vertical offset.
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.add_subtitle`

Add subtitle from metadata.

Type:

(?override : string, ?size : int, ?color : int, ?offset : int,
 source(video=canvas('A), 'a)) -> source(video=canvas('A), 'a)
where 'a is a set of tracks to be muxed into a source

Arguments:

override (of type string, which defaults to "subtitle"): Metadata where subtitle to display are located.
size (of type int, which defaults to 18)
color (of type int, which defaults to 16777215)
offset (of type int, which defaults to 20): Offset in pixels.
(unlabeled) (of type source(video=canvas('A), 'a) where 'a is a set of tracks to be muxed into a source): Source.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.add_text`

Add a text to a stream. Uses the first available operator in: camlimages, SDL, FFmpeg, GStreamer, gd or native.

Type:

(?id : string?, ?duration : float?, ?color : int, ?cycle : bool,
 ?font : {string}?, ?metadata : string?, ?size : int, ?speed : int,
 ?x : {int}, ?y : {int}, ?on_cycle : (() -> unit), {string},
 source(video=canvas('A), 'a).{is_ready : () -> bool}) ->
source(video=canvas('A), 'a)
where 'a is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
duration (of type float?, which defaults to null)
color (of type int, which defaults to 16777215): Text color (in 0xRRGGBB format).
cycle (of type bool, which defaults to true): Cycle text when it reaches left boundary.
font (of type {string}?, which defaults to null): Path to ttf font file.
metadata (of type string?, which defaults to null): Change text on a particular metadata (empty string means disabled).
size (of type int, which defaults to 18): Font size.
speed (of type int, which defaults to 0): Horizontal speed in pixels per second (0 means no scrolling and update according to x and y in case they are variable).
x (of type {int}, which defaults to 10): x offset.
y (of type {int}, which defaults to 10): y offset.
on_cycle (of type () -> unit, which defaults to {()}): Function called when text is cycling.
(unlabeled) (of type {string}): d Text to display.
(unlabeled) (of type source(video=canvas('A), 'a).{is_ready : () -> bool} where 'a is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.add_text.ffmpeg.internal`

Display a text.

Type:

(?id : string?, ?color : int, ?cycle : bool, ?font : string?,
 ?duration : float?, ?metadata : string?, ?size : int, ?speed : int,
 ?x : {int}, ?y : {int}, {string}, source(audio=pcm('b), video=canvas('a))) ->
source(audio=pcm('c), video=canvas('d))

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
color (of type int, which defaults to 16777215): Text color (in 0xRRGGBB format).
cycle (of type bool, which defaults to true): Cycle text when it reaches left boundary.
font (of type string?, which defaults to null): Path to ttf font file.
duration (of type float?, which defaults to null)
metadata (of type string?, which defaults to null): Change text on a particular metadata (empty string means disabled).
size (of type int, which defaults to 18): Font size.
speed (of type int, which defaults to 70): Horizontal speed in pixels per second (0 means no scrolling and update according to x and y in case they are variable).
x (of type {int}, which defaults to 10): x offset.
y (of type {int}, which defaults to 10): y offset.
(unlabeled) (of type {string}): d Text to display.
(unlabeled) (of type source(audio=pcm('b), video=canvas('a)))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.add_text.ffmpeg.raw`

Display a text. Use this operator inside ffmpeg filters with a input source

Type:

(?color : int, ?cycle : bool, ?font : string?, ?metadata : string?,
 ?size : int, ?speed : int, ?x : {int}, ?y : {int},
 graph : ffmpeg.filter.graph, ?{string}, source(video=ffmpeg.video.raw('a),
 'b)) -> ffmpeg.filter.video

Arguments:

color (of type int, which defaults to 16777215): Text color (in 0xRRGGBB format).
cycle (of type bool, which defaults to true): Cycle text when it reaches left boundary.
font (of type string?, which defaults to null): Path to ttf font file.
metadata (of type string?, which defaults to null): Change text on a particular metadata (empty string means disabled).
size (of type int, which defaults to 18): Font size.
speed (of type int, which defaults to 70): Horizontal speed in pixels per second (0 means no scrolling and update according to x and y in case they are variable).
x (of type {int}, which defaults to 10): x offset.
y (of type {int}, which defaults to 10): y offset.
graph (of type ffmpeg.filter.graph): a ffmpeg filter graph to attach this filter to.
(unlabeled) (of type {string}, which defaults to ""): d Text to display.
(unlabeled) (of type source(video=ffmpeg.video.raw('a), 'b))

`video.add_text.ffmpeg.raw.filter`

Display a text. Use this operator inside ffmpeg filters with a ffmpeg video input Returns a ffmpeg video output with on_change and on_metadata methods to be used to update the output text.

Type:

(?color : int, ?cycle : bool, ?font : string?, ?metadata : string?,
 ?size : int, ?speed : int, ?x : {int}, ?y : {int},
 graph : ffmpeg.filter.graph, ?{string}, ffmpeg.filter.video) ->
ffmpeg.filter.video

Arguments:

color (of type int, which defaults to 16777215): Text color (in 0xRRGGBB format).
cycle (of type bool, which defaults to true): Cycle text when it reaches left boundary.
font (of type string?, which defaults to null): Path to ttf font file.
metadata (of type string?, which defaults to null): Change text on a particular metadata (empty string means disabled).
size (of type int, which defaults to 18): Font size.
speed (of type int, which defaults to 70): Horizontal speed in pixels per second (0 means no scrolling and update according to x and y in case they are variable).
x (of type {int}, which defaults to 10): x offset.
y (of type {int}, which defaults to 10): y offset.
graph (of type ffmpeg.filter.graph): a ffmpeg filter graph to attach this filter to.
(unlabeled) (of type {string}, which defaults to ""): d Text to display.
(unlabeled) (of type ffmpeg.filter.video)

Methods:

on_change (of type () -> unit): Method to call when parameters have changed to update the filter’s rendered out, including when text changes.
on_metadata (of type ([string * string]) -> unit): Method to call on new metadata.

`video.add_text.native`

Add a text to a stream (native implementation).

Type:

(?id : string?, ?duration : float?, ?color : {int}, ?cycle : bool,
 ?font : {string}?, ?metadata : string?, ?size : {int}, ?speed : int,
 ?x : {int}, ?y : {int}, ?on_cycle : (() -> unit), {string},
 source(video=canvas('B), 'A).{is_ready : () -> bool}) ->
source(video=canvas('B), 'A)
where 'A is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
duration (of type float?, which defaults to null)
color (of type {int}, which defaults to 16777215): Text color (in 0xRRGGBB format).
cycle (of type bool, which defaults to true): Cycle text when it reaches left boundary.
font (of type {string}?, which defaults to null): Path to ttf font file.
metadata (of type string?, which defaults to null): Change text on a particular metadata (empty string means disabled).
size (of type {int}, which defaults to 18): Font size.
speed (of type int, which defaults to 0): Horizontal speed in pixels per second (0 means no scrolling and update according to x and y in case they are variable).
x (of type {int}, which defaults to 10): x offset.
y (of type {int}, which defaults to 10): y offset.
on_cycle (of type () -> unit, which defaults to {()})
(unlabeled) (of type {string}): d Text to display.
(unlabeled) (of type source(video=canvas('B), 'A).{is_ready : () -> bool} where 'A is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.add_text.sdl`

Add a text to a stream (SDL implementation).

Type:

(?id : string?, ?duration : float?, ?color : {int}, ?cycle : bool,
 ?font : {string}?, ?metadata : string?, ?size : {int}, ?speed : int,
 ?x : {int}, ?y : {int}, ?on_cycle : (() -> unit), {string},
 source(video=canvas('B), 'A).{is_ready : () -> bool}) ->
source(video=canvas('B), 'A)
where 'A is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
duration (of type float?, which defaults to null)
color (of type {int}, which defaults to 16777215): Text color (in 0xRRGGBB format).
cycle (of type bool, which defaults to true): Cycle text when it reaches left boundary.
font (of type {string}?, which defaults to null): Path to ttf font file.
metadata (of type string?, which defaults to null): Change text on a particular metadata (empty string means disabled).
size (of type {int}, which defaults to 18): Font size.
speed (of type int, which defaults to 0): Horizontal speed in pixels per second (0 means no scrolling and update according to x and y in case they are variable).
x (of type {int}, which defaults to 10): x offset.
y (of type {int}, which defaults to 10): y offset.
on_cycle (of type () -> unit, which defaults to {()})
(unlabeled) (of type {string}): d Text to display.
(unlabeled) (of type source(video=canvas('B), 'A).{is_ready : () -> bool} where 'A is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.align`

Translate the video so that it is aligned on boundaries.

Type:

(?id : string?, ?bottom : bool, ?left : bool, ?right : bool, ?top : bool,
 source(video=canvas('a), 'b)) -> source(video=canvas('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
bottom (of type bool, which defaults to false): Align bottom.
left (of type bool, which defaults to false): Align left.
right (of type bool, which defaults to false): Align right.
top (of type bool, which defaults to false): Align top.
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.alpha.movement`

Make moving parts visible and non-moving parts transparent. A cheap way to have a bluescreen.

Type:

(?id : string?, ?precision : float, source(video=canvas('a), 'b)) ->
source(video=canvas('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
precision (of type float, which defaults to 0.2): Precision when comparing pixels to those of previous image (between 0 and 1).
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.alpha.of_color`

Set a color to be transparent.

Type:

(?id : string?, ?color : int, ?precision : float, source(video=canvas('a),
 'b)) -> source(video=canvas('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
color (of type int, which defaults to 0): Color which should be transparent (in 0xRRGGBB format).
precision (of type float, which defaults to 0.2): Precision in color matching (0. means match precisely the color and 1. means match every color).
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.alpha.remove`

Remove α channel.

Type:

(?id : string?, source(video=canvas('a), 'b)) -> source(video=canvas('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.alpha.to_y`

Convert the α channel to Y channel, thus converting opaque (resp. transparent) pixels to bright (resp. dark) ones. This is useful to observe the α channel.

Type:

(?id : string?, source(video=canvas('a), 'b)) -> source(video=canvas('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.board`

A plane where one can draw.

Type:

(?id : string?, ?height : int?, ?width : int?) -> source('a)
where 'a is a set of internal tracks

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
height (of type int?, which defaults to null): Initial height of the video (defaults ot the same as frame).
width (of type int?, which defaults to null): Initial width of the video (defaults ot the same as frame).

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
clear (of type () -> unit): Clear the board.
clear_and_copy (of type (?x : int, ?y : int) -> unit): Clear the board and copy the old board to the new one, translated.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
fill (of type (int) -> unit): Fill with given color (0xRRGGBB).
height (of type () -> int): Current height of the board.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
line_to (of type (?color : int, int, int) -> unit): Draw a line from the last point.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
pixel (of type (int, int) -> (() -> int).{set : (int) -> unit}): Retrieve a pixel whose contents is a color (in 0xRRGGBB format).
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.
width (of type () -> int): Current width of the board.

`video.bounding_box`

Retrieve the origin (methods x / y) and the dimensions (methods width / height) of the bounding box of the video.

Type:

(?id : string?, source(video=canvas('a), 'b)) -> source(video=canvas('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
height (of type () -> int): Height of video.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.
width (of type () -> int): Width of video.
x (of type () -> int): x offset of video.
y (of type () -> int): y offset of video.

`video.color`

Generate a video filled with given color.

Type:

({int}) -> source(video=canvas('a), 'b) where 'b is a set of internal tracks

Arguments:

(unlabeled) (of type {int}): Color (in 0xRRGGBB format).

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.cover`

Generate a video source containing cover-art for current track of input audio source.

Type:

('b.{on_track : ((([string * string]) -> unit)) -> 'a}) ->
source(video=canvas('c))

Arguments:

(unlabeled) (of type 'b.{on_track : ((([string * string]) -> unit)) -> 'a}): Audio source whose metadata contain cover-art.

`video.crop`

Make the viewport of the current video match its bounding box.

Type:

(?id : string?, source(video=canvas('a), 'b)) -> source(video=canvas('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.fade.in`

Fade the beginning of tracks. Metadata ‘liq_video_fade_in’ can be used to set the duration for a specific track (float in seconds).

Type:

(?id : string?, ?duration : float, ?override : string, ?transition : string,
 ?type : string, source(video=canvas('a), 'b)) -> source(video=canvas('a),
'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
duration (of type float, which defaults to 3.): Duration of the fading. This value can be set on a per-file basis using the metadata field passed as override.
override (of type string, which defaults to "liq_video_fade_in"): Metadata field which, if present and containing a float, overrides the ‘duration’ parameter for current track.
transition (of type string, which defaults to "fade"): Kind of transition (fade|slide_left|slide_right|slide_up|slide_down|grow|disc|random).
type (of type string, which defaults to "lin"): Fader shape (lin|sin|log|exp): linear, sinusoidal, logarithmic or exponential.
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.fade.out`

Fade the end of tracks. Metadata ‘liq_video_fade_out’ can be used to set the duration for a specific track (float in seconds).

Type:

(?id : string?, ?duration : float, ?override : string, ?transition : string,
 ?type : string, source(video=canvas('a), 'b)) -> source(video=canvas('a),
'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
duration (of type float, which defaults to 3.): Duration of the fading. This value can be set on a per-file basis using the metadata field passed as override.
override (of type string, which defaults to "liq_video_fade_out"): Metadata field which, if present and containing a float, overrides the ‘duration’ parameter for current track.
transition (of type string, which defaults to "fade"): Kind of transition (fade|slide_left|slide_right|slide_up|slide_down|grow|disc|random).
type (of type string, which defaults to "lin"): Fader shape (lin|sin|log|exp): linear, sinusoidal, logarithmic or exponential.
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.fill`

Fill frame with a color.

Type:

(?id : string?, ?alpha : {float}, ?color : {int}, source(video=canvas('a),
 'b)) -> source(video=canvas('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
alpha (of type {float}, which defaults to 1.): Transparency of the color between 0 and 1 (0 is fully transparent and 1 is fully opaque).
color (of type {int}, which defaults to 0): Color to fill the image with (0xRRGGBB).
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.frame.height`

Height for all video frames.

Type:

() -> int

`video.frame.rate`

Framerate for all video frames.

Type:

() -> int

`video.frame.width`

Width for all video frames.

Type:

() -> int

`video.greyscale`

Convert video to greyscale.

Type:

(?id : string?, source(video=canvas('a), 'b)) -> source(video=canvas('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.hmirror`

Flip image horizontally.

Type:

(?id : string?, source(video=canvas('a), 'b)) -> source(video=canvas('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.info`

Compute various information about the video (dimension, size, etc.). Those are accessible through the methods attached to the source.

Type:

(?id : string?, source(video=canvas('a), 'b)) -> source(video=canvas('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
height (of type () -> int): Height of video.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
planes (of type () -> int): Number of planes in a video frame.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
size (of type () -> int): Size of a video frame (in bytes).
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.
width (of type () -> int): Width of video.

`video.invert`

Invert video.

Type:

(?id : string?, source(video=canvas('a), 'b)) -> source(video=canvas('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.lomo`

Emulate the “Lomo effect”.

Type:

(?id : string?, source(video=canvas('a), 'b)) -> source(video=canvas('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.opacity`

Scale opacity of video.

Type:

(?id : string?, {float}, source(video=canvas('a), 'b)) ->
source(video=canvas('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
(unlabeled) (of type {float}): Coefficient to scale opacity with.
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.opacity.box`

Set alpha value on a given box inside the image.

Type:

(?id : string?, alpha : {float}, height : {int}, width : {int}, ?x : {int},
 ?y : {int}, source(video=canvas('a), 'b)) -> source(video=canvas('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
alpha (of type {float}): alpha value.
height (of type {int}): Box height.
width (of type {int}): Box width.
x (of type {int}, which defaults to 0): x offset.
y (of type {int}, which defaults to 0): y offset.
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.persistence`

Make images of the video persistent.

Type:

(?id : string?, ?duration : {float}, source(video=canvas('a), 'b)) ->
source(video=canvas('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
duration (of type {float}, which defaults to 1.): Persistence duration in seconds.
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.plot`

Plot a floating point value.

Type:

(?lines : bool, ?min : float, ?max : float, ?speed : float, ?color : int,
 (() -> float)) -> source(video=canvas('a), 'b)
where 'b is a set of internal tracks

Arguments:

lines (of type bool, which defaults to true): Draw lines connecting plotted points.
min (of type float, which defaults to 0.): Minimal value of the parameter.
max (of type float, which defaults to 1.): Maximal value of the parameter.
speed (of type float, which defaults to 100.): Speed in pixels per second.
color (of type int, which defaults to 16777215): Color of the drawn point (in 0xRRGGBB format).
(unlabeled) (of type () -> float): Value to plot.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.render`

Render the video by computing the result of its canvas images.

Type:

(?id : string?, ?transparent : bool, source(video=canvas('a), 'b)) ->
source(video=canvas('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
transparent (of type bool, which defaults to true): Make uncovered portions of the image transparent (they are black by default).
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.resize`

Resize and translate video.

Type:

(?id : string?, ?height : {int}?, ?proportional : bool, ?width : {int}?,
 ?x : {int}, ?y : {int}, source(video=canvas('a), 'b)) ->
source(video=canvas('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
height (of type {int}?, which defaults to null): Target height (null means original height).
proportional (of type bool, which defaults to true): Keep original proportions.
width (of type {int}?, which defaults to null): Target width (null means original width).
x (of type {int}, which defaults to 0): x offset.
y (of type {int}, which defaults to 0): y offset.
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.rotate`

Rotate video.

Type:

(?id : string?, ?angle : {float}, source(video=canvas('a), 'b)) ->
source(video=canvas('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
angle (of type {float}, which defaults to 0.): Angle in radians.
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.scale`

Scale and translate video.

Type:

(?id : string?, ?scale : {float}, ?x : {int}, ?xscale : {float}, ?y : {int},
 ?yscale : {float}, source(video=canvas('a), 'b)) -> source(video=canvas('a),
'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
scale (of type {float}, which defaults to 1.): Scaling coefficient in both directions.
x (of type {int}, which defaults to 0): x offset.
xscale (of type {float}, which defaults to 1.): x scaling.
y (of type {int}, which defaults to 0): y offset.
yscale (of type {float}, which defaults to 1.): y scaling.
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.sepia`

Convert video to sepia.

Type:

(?id : string?, source(video=canvas('a), 'b)) -> source(video=canvas('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.slideshow`

Display a slideshow (typically of pictures).

Type:

(?id : string?, ?cyclic : {bool}, ?advance : {float}, ?[string]) ->
source('a)

Arguments:

id (of type string?, which defaults to null)
cyclic (of type {bool}, which defaults to true): Go to the first picture after the last.
advance (of type {float}, which defaults to -1.): Skip to the next file after this amount of time in seconds (negative means never).
(unlabeled) (of type [string], which defaults to []): List of files to display.

Methods:

append (of type ([string]) -> unit): Append a list of files to the slideshow.
buffered (of type () -> [string * float]): Length of buffered data.
clear (of type () -> unit): Clear the list of files in the slideshow.
current (of type () -> string): Currently displayed file.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
next (of type () -> unit): Go to next file.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
prev (of type () -> unit): Go to previous file.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
set (of type (source('A)) -> unit): Set the source.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.still_frame`

Take still frames from a video source by calling the save method. For now only bitmap output is supported.

Type:

(?id : string?, source(video=canvas('a), 'b)) -> source(video=canvas('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
save (of type (string) -> unit): Save current image, argument is the file name to save to.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.testsrc.ffmpeg`

A test video source, which generates various patterns.

Type:

(?id : string?, ?pattern : string, ?max_buffer : float, ?duration : 'a?) ->
source(video=canvas('b))

Arguments:

id (of type string?, which defaults to null)
pattern (of type string, which defaults to "testsrc"): Pattern drawn in the video: "testsrc", "testsrc2", "smptebars", "pal75bars", "pal100bars", "smptehdbars", "yuvtestsrc" or "rgbtestsrc" and more. Support any of the patterns supported by ffmpeg.
max_buffer (of type float, which defaults to 0.5): Maximum data buffer in seconds
duration (of type 'a?, which defaults to null): Duration of the source.

`video.text`

Display a text using the first available operator in: camlimages, SDL, FFmpeg, GStreamer, gd or native.

Type:

(?id : string?, ?color : {int}, ?duration : float?, ?font : {string}?,
 ?size : {int}, {string}) -> source(video=canvas('A))

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
color (of type {int}, which defaults to 16777215): Text color (in 0xRRGGBB format).
duration (of type float?, which defaults to null): Duration in seconds (null means infinite).
font (of type {string}?, which defaults to null): Path to ttf font file.
size (of type {int}, which defaults to 18): Font size.
(unlabeled) (of type {string}): Text to display.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.text.gd`

Add a text to a stream (GD implementation).

Type:

(?id : string?, ?duration : float?, ?color : {int}, ?cycle : bool,
 ?font : {string}?, ?metadata : string?, ?size : {int}, ?speed : int,
 ?x : {int}, ?y : {int}, ?on_cycle : (() -> unit), {string},
 source(video=canvas('B), 'A).{is_ready : () -> bool}) ->
source(video=canvas('B), 'A)
where 'A is a set of tracks to be muxed into a source

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
duration (of type float?, which defaults to null)
color (of type {int}, which defaults to 16777215): Text color (in 0xRRGGBB format).
cycle (of type bool, which defaults to true): Cycle text when it reaches left boundary.
font (of type {string}?, which defaults to null): Path to ttf font file.
metadata (of type string?, which defaults to null): Change text on a particular metadata (empty string means disabled).
size (of type {int}, which defaults to 18): Font size.
speed (of type int, which defaults to 0): Horizontal speed in pixels per second (0 means no scrolling and update according to x and y in case they are variable).
x (of type {int}, which defaults to 10): x offset.
y (of type {int}, which defaults to 10): y offset.
on_cycle (of type () -> unit, which defaults to {()})
(unlabeled) (of type {string}): d Text to display.
(unlabeled) (of type source(video=canvas('B), 'A).{is_ready : () -> bool} where 'A is a set of tracks to be muxed into a source)

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.text.native`

Display a text.

Type:

(?id : string?, ?color : {int}, ?duration : float?, ?font : {string}?,
 ?size : {int}, {string}) -> source(video=canvas('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
color (of type {int}, which defaults to 16777215): Text color (in 0xRRGGBB format).
duration (of type float?, which defaults to null): Duration in seconds (null means infinite).
font (of type {string}?, which defaults to null): Path to ttf font file (default is "/usr/share/fonts/truetype/dejavu/DejaVuSans.ttf").
size (of type {int}, which defaults to 18): Font size.
(unlabeled) (of type {string}): Text to display.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.text.sdl`

Display a text.

Type:

(?id : string?, ?color : {int}, ?duration : float?, ?font : {string}?,
 ?size : {int}, {string}) -> source(video=canvas('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
color (of type {int}, which defaults to 16777215): Text color (in 0xRRGGBB format).
duration (of type float?, which defaults to null): Duration in seconds (null means infinite).
font (of type {string}?, which defaults to null): Path to ttf font file (default is "/usr/share/fonts/truetype/dejavu/DejaVuSans.ttf").
size (of type {int}, which defaults to 18): Font size.
(unlabeled) (of type {string}): Text to display.

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.tile`

Tile sources

Type:

(?id : string?, ?normalize : {bool}, ?power : {bool}, ?proportional : bool,
 ?weights : [{float}], [source(?audio=pcm('b), video=canvas('a), 'c)]) ->
source(?audio=pcm('b), video=canvas('a))

Arguments:

id (of type string?, which defaults to "video.tile"): Force the value of the track ID.
normalize (of type {bool}, which defaults to true): Divide by the sum of weights of ready sources (or by the number of ready sources if weights are not specified).
power (of type {bool}, which defaults to false): Perform constant-power normalization.
proportional (of type bool, which defaults to true): Scale preserving the proportions.
weights (of type [{float}], which defaults to [])
(unlabeled) (of type [source(?audio=pcm('b), video=canvas('a), 'c)])

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.translate`

Translate video.

Type:

(?id : string?, ?x : {int}, ?y : {int}, source(video=canvas('a), 'b)) ->
source(video=canvas('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
x (of type {int}, which defaults to 0): x offset.
y (of type {int}, which defaults to 0): y offset.
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.viewport`

Set the viewport for the current video.

Type:

(?id : string?, ?height : int?, ?width : int?, ?x : int, ?y : int,
 source(video=canvas('a), 'b)) -> source(video=canvas('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
height (of type int?, which defaults to null): height (default is frame height).
width (of type int?, which defaults to null): Width (default is frame width).
x (of type int, which defaults to 0): Horizontal offset.
y (of type int, which defaults to 0): Vertical offset.
(unlabeled) (of type source(video=canvas('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

Source / Visualization

`bpm`

Detect the BPM (number of beats per minute). The returned source has a method bpm, which can be called to compute it.

Type:

(?id : string?, source(audio=pcm('a), 'b)) -> source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

bpm (of type () -> float): Compute the current BPM.
buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`lufs`

Compute current LUFS of the source according to the EBU R128 standard. It returns the source with a method to compute the current value.

Type:

(?id : string?, ?window : {float}, source(audio=pcm('a), 'b)) ->
source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
window (of type {float}, which defaults to 3.): Duration of the window (in seconds) used to compute the LUFS.
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
lufs (of type () -> float): Current value for the LUFS (short-term value computed over the duration specified by the window parameter).
lufs_momentary (of type () -> float): Momentary LUFS (over a 400ms window).
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`midi.inspect`

Display midi events on standard output.

Type:

(?id : string?, source('a)) -> source('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
(unlabeled) (of type source('a))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`rms.smooth`

Compute the current RMS for the source, this varies more smoothly that rms and is updated more frequently. Returns the source with a method rms.

Type:

(?id : string?, ?duration : {float}, source(audio=pcm('a), 'b)) ->
source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
duration (of type {float}, which defaults to 0.5): Duration of the window in seconds (more precisely, this is the time constant of the low-pass filter).
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
rms (of type () -> float): Current value for the RMS.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

`video.volume`

Graphical visualization of the sound.

Type:

(?id : string?, source(audio=pcm('a), 'b)) -> source(audio=pcm('a), 'b)

Arguments:

id (of type string?, which defaults to null): Force the value of the source ID.
(unlabeled) (of type source(audio=pcm('a), 'b))

Methods:

buffered (of type () -> [string * float]): Length of buffered data.
duration (of type () -> float): Estimation of the duration of the current track.
elapsed (of type () -> float): Elapsed time in the current track.
fallible (of type bool): Indicate if a source may fail, i.e. may not be ready to stream.
id (of type () -> string): Identifier of the source.
is_active (of type () -> bool): true if the source is active, i.e. it is continuously animated by its own clock whenever it is ready. Typically, true for outputs and sources such as input.http.
is_ready (of type () -> bool): Indicate if a source is ready to stream. This does not mean that the source is currently streaming, just that its resources are all properly initialized.
is_up (of type () -> bool): Indicate that the source can be asked to produce some data at any time. This is true when the source is currently being used or if it could be used at any time, typically inside a switch or fallback.
last_metadata (of type () -> [string * string]?): Return the last metadata from the source.
log (of type {level : (() -> int?).{set : (int) -> unit}}): Get or set the source’s log level, from 1 to 5.
on_metadata (of type ((([string * string]) -> unit)) -> unit): Call a given handler on metadata packets.
on_shutdown (of type ((() -> unit)) -> unit): Register a function to be called when source shuts down.
on_track (of type ((([string * string]) -> unit)) -> unit): Call a given handler on new tracks.
on_wake_up (of type ((() -> unit)) -> unit): Register a function to be called after the source is asked to get ready. This is when, for instance, the source’s final ID is set.
remaining (of type () -> float): Estimation of remaining time in the current track.
seek (of type (float) -> float): Seek forward, in seconds (returns the amount of time effectively seeked).
self_sync (of type () -> bool): Is the source currently controlling its own real-time loop.
skip (of type () -> unit): Skip to the next track.
time (of type () -> float): Get a source’s time, based on its assigned clock.

String

`%`

pattern % [...,(k,v),...] changes in the pattern occurrences of:

$(k) into v
`$(if $(k2),“a”,“b”) into “a” if k2 is found in the list, “b” otherwise.

Type:

(string, [string * string]) -> string

Arguments:

(unlabeled) (of type string)
(unlabeled) (of type [string * string])

`^`

Concatenate strings.

Type:

(string, string) -> string

Arguments:

(unlabeled) (of type string)
(unlabeled) (of type string)

`bool_of_string`

Convert a string to a bool. Raises error.failure("a string to a bool") if conversion fails and default is null

Type:

(string, ?default : bool?) -> bool

Arguments:

(unlabeled) (of type string)
default (of type bool?, which defaults to null)

`file.metadata.flac.cover.decode`

Decode a flac-encoded cover metadata string.

Type:

(string) -> string
.{
  color_depth : int,
  description : string,
  height : int,
  mime : string,
  number_of_colors : int?,
  picture_type : int,
  width : int}?

Arguments:

(unlabeled) (of type string)

`file.metadata.flac.cover.encode`

Encode cover metadata for embedding with flac files.

Type:

(picture_type : int, mime : string, ?description : string, width : int,
 height : int, color_depth : int, ?number_of_colors : int?, string) -> string

Arguments:

picture_type (of type int)
mime (of type string)
description (of type string, which defaults to "")
width (of type int)
height (of type int)
color_depth (of type int)
number_of_colors (of type int?, which defaults to null)
(unlabeled) (of type string)

`float_of_string`

Convert a string to a float. Raises error.failure("a string to a float") if conversion fails and default is null

Type:

(string, ?default : float?) -> float

Arguments:

(unlabeled) (of type string)
default (of type float?, which defaults to null)

`int_of_string`

Convert a string to a int. Raises error.failure("a string to a int") if conversion fails and default is null

Type:

(string, ?default : int?) -> int

Arguments:

(unlabeled) (of type string)
default (of type int?, which defaults to null)

`irc.channel`

Contents of an IRC channel.

Type:

(?server : string, ?port : int, ?channel : string, ?nick : string,
 ?limit : int) -> () -> string

Example:

# Display messages in the #liquidsoap-test room over a video
s = single("test.mp4")
s = video.add_text.native(irc.channel(channel="#liquidsoap-test"), s)

Arguments:

server (of type string, which defaults to "irc.libera.chat"): IRC server.
port (of type int, which defaults to 6667): Port for IRC server.
channel (of type string, which defaults to "#liquidsoap"): IRC chan to join.
nick (of type string, which defaults to "liquidbot"): Nickname.
limit (of type int, which defaults to 10): Limit to n last messages

`json`

Create a generic json object

Type:

() -> json

Methods:

add (of type (string, 'a) -> unit): Add or replace a new key/value pair to the object.
remove (of type (string) -> unit): Remove a key from the object. Does not nothing if the key does not exist.
stringify (of type (?compact : bool, ?json5 : bool) -> string): Render object as json string.

`json.stringify`

Convert a value to JSON. If the value cannot be represented as JSON (for instance a function), a error.json exception is raised.

Type:

(?compact : bool, ?json5 : bool, 'a) -> string

Arguments:

compact (of type bool, which defaults to false): Output compact text.
json5 (of type bool, which defaults to false): Use json5 extended spec.
(unlabeled) (of type 'a)

`metadata.id3v2.render`

Return a string representation of a id3v2 metadata tag

Type:

([string * string], ?version : int) -> string

Arguments:

(unlabeled) (of type [string * string])
version (of type int, which defaults to 3): Tag version. One of: 3 or 4

`regexp`

Create a regular expression

Type:

(?flags : [string], string) -> regexp

Arguments:

flags (of type [string], which defaults to []): List of flags. Valid flags: "i", "g", "s", "m".
(unlabeled) (of type string)

Methods:

exec (of type (string) -> [int * string].{groups : [string * string]}): Extract substrings from a string. Returns a list of (index,value). If the list does not have a pair associated to some index, it means that the corresponding pattern was not found.
replace (of type (((string) -> string), string) -> string): Replace substrings matched by the regexp by another string returned by a function.
split (of type (string) -> [string]): Split a string on the given regular expression.
test (of type (string) -> bool): Match a string with the expressionn.

`runtime.mem_usage.prettify_bytes`

Returns a human-redable description of an amount of bytes.

Type:

(?float_printer : ((float) -> string)?, ?signed : bool?, ?bits : bool?,
 ?binary : bool?, int) -> string

Arguments:

float_printer (of type ((float) -> string)?, which defaults to null)
signed (of type bool?, which defaults to null)
bits (of type bool?, which defaults to null)
binary (of type bool?, which defaults to null)
(unlabeled) (of type int)

`string`

Return the representation of a value.

Type:

(?fields : bool, 'a) -> string

Arguments:

fields (of type bool, which defaults to false): Show toplevel fields around the value.
(unlabeled) (of type 'a)

`string.annotate.parse`

Parse a string of the form <key>=<value>,...:<uri> as given by the annotate: protocol

Type:

(string) -> [string * string] * string

Arguments:

(unlabeled) (of type string)

`string.base64.decode`

Decode a Base64 encoded string.

Type:

(string) -> string

Arguments:

(unlabeled) (of type string)

`string.base64.encode`

Encode a string in Base64.

Type:

(string) -> string

Arguments:

(unlabeled) (of type string)

`string.binary.of_int`

Encode a positive (unsigned) integer using native memory representation.

Type:

(?pad : int, ?little_endian : bool, int) -> string

Arguments:

pad (of type int, which defaults to 0): Minimum length in digits (pad on the left with zeros in order to reach it)
little_endian (of type bool, which defaults to true): Whether the memory representation is little endian.
(unlabeled) (of type int): String containing the binary representation.

`string.binary.to_int`

Value of a positive (unsigned) integer encoded using native memory representation.

Type:

(?little_endian : bool, string) -> int

Arguments:

little_endian (of type bool, which defaults to true): Whether the memory representation is little endian.
(unlabeled) (of type string): String containing the binary representation.

`string.capitalize`

Return a string with the first character set to upper case (capitalize), or to lower case (uncapitalize).

Type:

(?capitalize : bool, ?space_sensitive : bool, string) -> string

Arguments:

capitalize (of type bool, which defaults to true): Capitalize if true, uncapitalize otherwise
space_sensitive (of type bool, which defaults to true): Capitalize each space separated sub-string.
(unlabeled) (of type string)

`string.case`

Convert a string to lower or upper case.

Type:

(?lower : bool, string) -> string

Arguments:

lower (of type bool, which defaults to true): Convert to lower case if true and uppercase otherwise.
(unlabeled) (of type string)

`string.char`

Create a string with one character.

Type:

(int) -> string

Arguments:

(unlabeled) (of type int): Code of the character.

`string.char.ascii.random`

Return a random ASCII character

Type:

(?[int]) -> string

Arguments:

(unlabeled) (of type [int], which defaults to [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127])

`string.concat`

Concatenate strings.

Type:

(?separator : string, [string]) -> string

Arguments:

separator (of type string, which defaults to "")
(unlabeled) (of type [string])

`string.contains`

Test whether a string contains a given prefix, substring or suffix.

Type:

(?prefix : string, ?substring : string, ?suffix : string, string) -> bool

Arguments:

prefix (of type string, which defaults to ""): Prefix to look for.
substring (of type string, which defaults to ""): Substring to look for.
suffix (of type string, which defaults to ""): Suffix to look for.
(unlabeled) (of type string): The string to look into.

`string.data_uri.decode`

Decode a string using the data uri format, i.e. "data:<mime>[;base64],<data>".

Type:

(string) -> string.{mime : string}?

Arguments:

(unlabeled) (of type string)

`string.data_uri.encode`

Encode a string using the data uri format, i.e. "data:<mime>[;base64],<data>".

Type:

(?base64 : bool, mime : string, string) -> string

Arguments:

base64 (of type bool, which defaults to true): Encode data using the base64 format
mime (of type string): Data mime type
(unlabeled) (of type string)

`string.escape`

Escape special characters in an string. By default, the string is assumed to be "utf8" encoded and is escaped following JSON and javascript specification.

Type:

(?special_char : ((encoding : string, string) -> bool)?,
 ?escape_char : ((encoding : string, string) -> string)?,
 ?encoding : string?, string) -> string

Arguments:

special_char (of type ((encoding : string, string) -> bool)?, which defaults to null): Return true if the given character (passed as a string) should be escaped. Defaults to control characters for "utf8" and control characters and any character above \x7E (non-printable characters) for "ascii".
escape_char (of type ((encoding : string, string) -> string)?, which defaults to null): Function used to escape a character. Defaults to \xxx octal notation for "ascii" and \uxxxx hexadecimal notation for "utf8".
encoding (of type string?, which defaults to null): One of: "ascii" or "utf8". If null, utf8 is tried first and ascii is used as a fallback if this fails.
(unlabeled) (of type string)

`string.escape.all`

Escape each character in the given string using a specific escape sequence.

Type:

(?format : string, string) -> string

Arguments:

format (of type string, which defaults to "utf8"): Escape format. One of: "octal", "hex" or "utf8".
(unlabeled) (of type string)

`string.escape.special_char`

Default function to detect characters to escape. See string.escape for more details.

Type:

(?encoding : string, string) -> bool

Arguments:

encoding (of type string, which defaults to "utf8"): One of: "ascii" or "utf8".
(unlabeled) (of type string)

`string.extract`

Extract substrings from a string. Perl compatible regular expressions are recognized. Hence, special characters should be escaped. Returns a list of (index,value). If the list does not have a pair associated to some index, it means that the corresponding pattern was not found. Alter natively, one can use the r/_/.exec(_) syntax for regular expressions.

Type:

(pattern : string, string) -> [int * string]

Arguments:

pattern (of type string)
(unlabeled) (of type string)

Methods:

groups (of type [string * string]): Named captures

`string.float`

String representation of a float.

Type:

(?decimal_places : int?, float) -> string

Arguments:

decimal_places (of type int?, which defaults to null): Number of decimal places.
(unlabeled) (of type float)

`string.getter.concat`

Combine a list of string getters [g1, ...] and return a single getter g such that: string.getter.flush(separator=s, g) = string.concat(separator=s, list.filter(fun (s) -> s != "", [string.getter.flush(g1), ...]))

Type:

([{string}]) -> {string}

Arguments:

(unlabeled) (of type [{string}])

`string.getter.flush`

Flush all values from a string getter and return the concatenated result. If the getter is constant, return the constant string. Otherwise, call the getter repeatedly until it returns an empty string and return the concatenated result

Type:

(?separator : string, {string}) -> string

Arguments:

separator (of type string, which defaults to "")
(unlabeled) (of type {string})

`string.getter.single`

Create a string getter which will return once the given string and then the empty string.

Type:

(string) -> () -> string

Arguments:

(unlabeled) (of type string)

`string.hex_of_int`

Hexadecimal representation of an integer.

Type:

(?pad : int, int) -> string

Arguments:

pad (of type int, which defaults to 0): Minimum length in digits (pad on the left with zeros in order to reach it).
(unlabeled) (of type int)

`string.id`

Generate an identifier with given operator name.

Type:

(string) -> string

Arguments:

(unlabeled) (of type string): Operator name.

`string.id.default`

Generate an identifier if no identifier was provided.

Type:

(default : string, string?) -> string

Arguments:

default (of type string): Name from which identifier is generated if not present.
(unlabeled) (of type string?): Proposed identifier.

`string.index`

Index where a substring occurs in a string. The function returns -1 if the substring is not present

Type:

(substring : string, string) -> int

Arguments:

substring (of type string): Substring to look for.
(unlabeled) (of type string): String in which to look.

`string.is_int`

Test whether a string is a valid integer.

Type:

(string) -> bool

Arguments:

(unlabeled) (of type string)

`string.length`

Get the length of a string.

Type:

(string) -> int

Arguments:

(unlabeled) (of type string)

`string.make`

Create a string of a given length using the given character.

Type:

(?char_code : int, int) -> string

Arguments:

char_code (of type int, which defaults to 32): Character code.
(unlabeled) (of type int): String length.

`string.match`

Match a string with an expression. Perl compatible regular expressions are recognized. Hence, special characters should be escaped. Alternatively, one can use the the r/_/.test(_) syntax for regular expressions.

Type:

(pattern : string, string) -> bool

Arguments:

pattern (of type string)
(unlabeled) (of type string)

`string.nth`

Retrieve a character in a string. Raises error.not_found if character does not exist.

Type:

(string, int) -> int

Example:

c = string.nth("abcde", 2)
print(c) # should print 99 which is the ascii code for "c"

Arguments:

(unlabeled) (of type string): String to look into.
(unlabeled) (of type int): Index of the character.

`string.null_terminated`

Add a null character at the end of a string.

Type:

(string) -> string

Arguments:

(unlabeled) (of type string): String.

`string.quote`

Return a quoted copy of the given string. By default, the string is assumed to be "utf8" encoded and is escaped following JSON and javascript specification.

Type:

(?encoding : string?, string) -> string

Arguments:

encoding (of type string?, which defaults to null): One of: "ascii" or "utf8". If null, utf8 is tried first and ascii is used as a fallback if this fails.
(unlabeled) (of type string)

`string.recode`

Convert a string. Effective only if Camomile is enabled.

Type:

(?in_enc : string?, ?out_enc : string, string) -> string

Arguments:

in_enc (of type string?, which defaults to null): Input encoding. Autodetected if null.
out_enc (of type string, which defaults to "UTF-8"): Output encoding.
(unlabeled) (of type string)

`string.replace`

Replace all substrings matched by a pattern by another string returned by a function. Alternatively, one can use the r/_/g.replace(_) syntax for regular expressions.

Type:

(pattern : string, ((string) -> string), string) -> string

Arguments:

pattern (of type string): Pattern (regular expression) of substrings which should be replaced.
(unlabeled) (of type (string) -> string): Function getting a matched substring an returning the string to replace it with.
(unlabeled) (of type string): String whose substrings should be replaced.

`string.residual`

What remains of a string after a given prefix.

Type:

(prefix : string, string) -> string?

Arguments:

prefix (of type string): Requested prefix.
(unlabeled) (of type string)

`string.split`

Split a string at “separator”. Perl compatible regular expressions are recognized. Hence, special characters should be escaped. Alternatively, one can use the r/_/.split(_) syntax for regular expressions.

Type:

(separator : string, string) -> [string]

Arguments:

separator (of type string)
(unlabeled) (of type string)

`string.split.first`

Split a string in two at first “separator”.

Type:

(separator : string, string) -> string * string

Arguments:

separator (of type string)
(unlabeled) (of type string)

`string.sub`

Get a substring of a string. Returns “” if no such substring exists.

Type:

(string, start : int, length : int) -> string

Arguments:

(unlabeled) (of type string)
start (of type int): Return a sub string starting at this position. First position is 0.
length (of type int): Return a sub string of length characters.

`string.to_float`

Convert a string to a float.

Type:

(?default : float, string) -> float

Arguments:

default (of type float, which defaults to 0.)
(unlabeled) (of type string)

`string.to_int`

Convert a string to a int.

Type:

(?default : int, string) -> int

Arguments:

default (of type int, which defaults to 0)
(unlabeled) (of type string)

`string.trim`

Return a string without leading and trailing whitespace.

Type:

(string) -> string

Arguments:

(unlabeled) (of type string)

`string.unescape`

This function is the inverse of string.escape.

Type:

(string) -> string

Arguments:

(unlabeled) (of type string)

`string.unquote`

Return an unquoted copy of the given string. Quotes are removed by trying to parse the string following the JSON string escaping convention.

Type:

(string) -> string

Arguments:

(unlabeled) (of type string)

`string_of_metadata`

Standard function for displaying metadata. Shows artist and title, using “Unknown” when a field is empty.

Type:

([string * string]) -> string

Arguments:

(unlabeled) (of type [string * string]): Metadata packet to be displayed.

`url.decode`

Decode an encoded url (e.g. “%20” becomes ” “).

Type:

(?plus : bool, string) -> string

Arguments:

plus (of type bool, which defaults to true)
(unlabeled) (of type string)

`url.encode`

Encode an url (e.g. ” ” becomes “%20”).

Type:

(?plus : bool, string) -> string

Arguments:

plus (of type bool, which defaults to true)
(unlabeled) (of type string)

`url.split`

Split an url of the form foo?arg=bar&arg2=bar2 into ("foo",[("arg","bar"),("arg2","bar2")]). The returned strings are decoded (see url.decode).

Type:

(string) -> string * [string * string]

Arguments:

(unlabeled) (of type string): Url to split.

`url.split_args`

Split the arguments of an url of the form arg=bar&arg2=bar2 into [("arg","bar"),("arg2","bar2")]. The returned strings are decoded (see url.decode).

Type:

(string) -> [string * string]

Arguments:

(unlabeled) (of type string): Argument string to split.

`yaml.stringify`

Convert a value to YAML. If the value cannot be represented as YAML (for instance a function), a error.yaml exception is raised.

Type:

(?scalar_style : string, ?layout_style : string, 'a) -> string

Arguments:

scalar_style (of type string, which defaults to "any"): Scalar style. One of: “any”, “plain”, “single_quoted”, “double_quoted”, “literal” or “folded”.
layout_style (of type string, which defaults to "any"): Layout style. One of: “any”, “block” or “flow”.
(unlabeled) (of type 'a)

System

`argv`

Get command-line parameters. The parameters are numbered starting from 1, the zeroth parameter being the script name.

Type:

(?default : string, int) -> string

Arguments:

default (of type string, which defaults to "")
(unlabeled) (of type int)

`environment`

Return the process environment.

Type:

() -> [string * string]

`environment.get`

Get the value of an environment variable. Returns default if the variable is not set.

Type:

(?default : string, string) -> string

Arguments:

default (of type string, which defaults to "")
(unlabeled) (of type string)

`environment.set`

Set the value associated to a variable in the process environment.

Type:

(string, string) -> unit

Arguments:

(unlabeled) (of type string): Variable to be set.
(unlabeled) (of type string): Value to set.

`exe_ext`

Executable file extension.

Type:

string

`exit`

Immediately stop the application. This should only be used in extreme cases or to specify an exit value. The recommended way of stopping Liquidsoap is to use shutdown.

Type:

(int) -> unit

Arguments:

(unlabeled) (of type int): Exit value.

`getopt`

Parse command line options: getopt("-o") returns “1” if “-o” was passed without any parameter, “0” otherwise. getopt(default="X","-o") returns “Y” if “-o Y” was passed, “X” otherwise. The result is removed from the list of arguments, affecting subsequent calls to argv() and getopt().

Type:

(?default : string, string) -> string

Arguments:

default (of type string, which defaults to "")
(unlabeled) (of type string)

`on_cleanup`

Type:

((() -> unit)) -> unit

Arguments:

(unlabeled) (of type () -> unit)

`on_shutdown`

Type:

((() -> unit)) -> unit

Arguments:

(unlabeled) (of type () -> unit)

`on_start`

Type:

((() -> unit)) -> unit

Arguments:

(unlabeled) (of type () -> unit)

`os.type`

Type of OS running liquidsoap.

Type:

string

`process.pid`

Get the process’ pid.

Type:

() -> int

`process.quote`

Return a quoted copy of the given string, suitable for use as one argument in a command line, escaping all meta-characters. Warning: under Windows, the output is only suitable for use with programs that follow the standard Windows quoting conventions.

Type:

(string) -> string

Arguments:

(unlabeled) (of type string): String to escape

`process.quote.command`

Return a quoted command line, suitable for use as an argument to process.run.

The optional arguments stdin, stdout and stderr are file names used to redirect the standard input, the standard output, or the standard error of the command.

If stdin=f is given, a redirection < f is performed and the standard input of the command reads from file f.

If stdout=f is given, a redirection > f is performed and the standard output of the command is written to file f.

If stderr=f is given, a redirection 2> f is performed and the standard error of the command is written to file f.

If both stdout=f and stderr=f are given, with the exact same file name f, a 2>&1 redirection is performed so that the standard output and the standard error of the command are interleaved and redirected to the same file f.

Type:

(?stdin : string?, ?stdout : string?, ?stderr : string?, ?args : [string],
 string) -> string

Arguments:

stdin (of type string?, which defaults to null): command standard input
stdout (of type string?, which defaults to null): command standard output
stderr (of type string?, which defaults to null): command standard error
args (of type [string], which defaults to []): command arguments
(unlabeled) (of type string): Command to execute

`process.read`

Perform a shell call and return its output.

Type:

(?timeout : float, ?env : [string * string], ?inherit_env : bool,
 ?log_errors : bool, string) -> string

Arguments:

timeout (of type float, which defaults to -1.): Cancel process after timeout has elapsed. Ignored if negative.
env (of type [string * string], which defaults to []): Process environment
inherit_env (of type bool, which defaults to true): Inherit calling process’s environment when env parameter is empty.
log_errors (of type bool, which defaults to true): Log details if the command does not return 0.
(unlabeled) (of type string): Command to run

`process.read.lines`

Perform a shell call and return the list of its output lines.

Type:

(?timeout : float, ?env : [string * string], ?inherit_env : bool,
 ?log_errors : bool, string) -> [string]

Arguments:

timeout (of type float, which defaults to -1.): Cancel process after timeout has elapsed. Ignored if negative.
env (of type [string * string], which defaults to []): Process environment
inherit_env (of type bool, which defaults to true): Inherit calling process’s environment when env parameter is empty.
log_errors (of type bool, which defaults to true): Log details if the command does not return 0.
(unlabeled) (of type string): Command to run

`process.run`

Run a process in a shell environment. Returns the standard output, as well as standard error and status as methods. The status can be “exit” (the status code is set), “killed” or “stopped” (the status code is the signal), or “exception” (the description is set) or “timeout” (the description is the run time).

Type:

(?env : [string * string], ?inherit_env : bool, ?rwdirs : [string],
 ?rodirs : [string], ?network : bool?, ?timeout : float?, string) -> unit

Arguments:

env (of type [string * string], which defaults to []): Process environment
inherit_env (of type bool, which defaults to true): Inherit calling process’s environment when env parameter is empty.
rwdirs (of type [string], which defaults to ["default"]): Read/write directories for sandboxing. "default" expands to sandbox default.
rodirs (of type [string], which defaults to ["default"]): Read-only directories for sandboxing "default" expands to sandbox default.
network (of type bool?, which defaults to null): Enable or disable network inside sandboxed environment (sandbox default if not specified).
timeout (of type float?, which defaults to null): Cancel process after timeout has elapsed. Ignored if negative.
(unlabeled) (of type string): Command to run

Methods:

status (of type string.{code : int, description : string}): Status when process ended, can be one of "exit" (the program exited, the status code is then relevant), "killed" (the program was killed by signal given in status code), "stopped" (the program was stopped by signal given in status code) or "exception" (the program raised and exception detailed in the description).
stderr (of type string): Messages written by process on standard error stream.
stdout (of type string): Messages written by process on standard output stream.

`process.stderr`

The process’ stderr

Type:

socket
.{
  close : () -> unit,
  non_blocking : (bool) -> unit,
  read : ((?timeout : float?) -> string)
  .{wait : (?timeout : float?, (() -> unit)) -> unit
  },
  type : string,
  write : ((?timeout : float?, string) -> unit)
  .{wait : (?timeout : float?, (() -> unit)) -> unit
  }
}

`process.stdin`

The process’ stdin

Type:

socket
.{
  close : () -> unit,
  non_blocking : (bool) -> unit,
  read : ((?timeout : float?) -> string)
  .{wait : (?timeout : float?, (() -> unit)) -> unit
  },
  type : string,
  write : ((?timeout : float?, string) -> unit)
  .{wait : (?timeout : float?, (() -> unit)) -> unit
  }
}

`process.stdout`

The process’ stdout

Type:

socket
.{
  close : () -> unit,
  non_blocking : (bool) -> unit,
  read : ((?timeout : float?) -> string)
  .{wait : (?timeout : float?, (() -> unit)) -> unit
  },
  type : string,
  write : ((?timeout : float?, string) -> unit)
  .{wait : (?timeout : float?, (() -> unit)) -> unit
  }
}

`process.test`

Return true if process exited with 0 code.

Type:

(?timeout : float, ?env : [string * string], ?inherit_env : bool, string) ->
bool

Arguments:

timeout (of type float, which defaults to -1.): Cancel process after timeout has elapsed. Ignored if negative.
env (of type [string * string], which defaults to []): Process environment
inherit_env (of type bool, which defaults to true): Inherit calling process’s environment when env parameter is empty.
(unlabeled) (of type string): Command to test

`process.time`

Get the execution time of the current liquidsoap process.

Type:

() -> unit

Methods:

system (of type float)
user (of type float)

`read`

Read some value from standard input (console).

Type:

(?hide : bool) -> string

Arguments:

hide (of type bool, which defaults to false): Hide typed characters (for passwords).

`reopen.stderr`

Reopen standard error on the given file

Type:

(string) -> unit

Arguments:

(unlabeled) (of type string)

`reopen.stdin`

Reopen standard input on the given file

Type:

(string) -> unit

Arguments:

(unlabeled) (of type string)

`reopen.stdout`

Reopen standard output on the given file

Type:

(string) -> unit

Arguments:

(unlabeled) (of type string)

`restart`

Restart the application.

Type:

() -> unit

`runtime.gc.get`

Return the current values of the GC parameters

Type:

() -> unit

Methods:

allocation_policy (of type int)
custom_major_ratio (of type int)
custom_minor_max_size (of type int)
custom_minor_ratio (of type int)
major_heap_increment (of type int)
max_overhead (of type int)
minor_heap_size (of type int)
space_overhead (of type int)
stack_limit (of type int)
verbose (of type int)
window_size (of type int)

`runtime.gc.print_stat`

Print the current values of the memory management counters in human-readable form.

Type:

() -> unit

`runtime.gc.quick_stat`

Same as stat except that live_words, live_blocks, free_words, free_blocks, largest_free, and fragments are set to 0. This function is much faster than gc.stat because it does not need to go through the heap.

Type:

() -> unit

Methods:

compactions (of type int)
fragments (of type int)
free_blocks (of type int)
free_words (of type int)
heap_chunks (of type int)
heap_words (of type int)
largest_free (of type int)
live_blocks (of type int)
live_words (of type int)
major_collections (of type int)
major_words (of type float)
minor_collections (of type int)
minor_words (of type float)
promoted_words (of type float)
stack_size (of type int)
top_heap_words (of type int)

`runtime.gc.set`

Set the GC parameters.

Type:

(
 {
   allocation_policy : int,
   custom_major_ratio : int,
   custom_minor_max_size : int,
   custom_minor_ratio : int,
   major_heap_increment : int,
   max_overhead : int,
   minor_heap_size : int,
   space_overhead : int,
   stack_limit : int,
   verbose : int,
   window_size : int
 }) -> unit

Arguments:

(unlabeled) (of type { allocation_policy : int, custom_major_ratio : int, custom_minor_max_size : int, custom_minor_ratio : int, major_heap_increment : int, max_overhead : int, minor_heap_size : int, space_overhead : int, stack_limit : int, verbose : int, window_size : int })

`runtime.gc.stat`

Return the current values of the memory management counters. This function examines every heap block to get the statistics.

Type:

() -> unit

Methods:

compactions (of type int)
fragments (of type int)
free_blocks (of type int)
free_words (of type int)
heap_chunks (of type int)
heap_words (of type int)
largest_free (of type int)
live_blocks (of type int)
live_words (of type int)
major_collections (of type int)
major_words (of type float)
minor_collections (of type int)
minor_words (of type float)
promoted_words (of type float)
stack_size (of type int)
top_heap_words (of type int)

`runtime.jemalloc.epoch`

Refresh the epoch counter for statistics

Type:

() -> unit

`runtime.jemalloc.mallctl.bool`

Get an option of type bool using mallctl. Returned value has the same type as a reference.

Type:

(string) -> () -> bool

Arguments:

(unlabeled) (of type string): Option name

Methods:

set (of type (bool) -> unit): Set option value

`runtime.jemalloc.mallctl.flag`

Set an option flag

Type:

(string) -> unit

Arguments:

(unlabeled) (of type string): Flag name

`runtime.jemalloc.mallctl.int`

Get an option of type int using mallctl. Returned value has the same type as a reference.

Type:

(string) -> () -> int

Arguments:

(unlabeled) (of type string): Option name

Methods:

set (of type (int) -> unit): Set option value

`runtime.jemalloc.mallctl.string`

Get an option of type string using mallctl. Returned value has the same type as a reference.

Type:

(string) -> () -> string

Arguments:

(unlabeled) (of type string): Option name

Methods:

set (of type (string) -> unit): Set option value

`runtime.jemalloc.memory_stats`

Return memory allocation stats from jemalloc.

Type:

() -> unit

Methods:

active (of type int)
allocated (of type int)
mapped (of type int)
resident (of type int)

`runtime.jemalloc.version`

Jemalloc version information

Type:

() -> string

Methods:

git_version (of type string): Git version
major (of type int): Major version
minor (of type int): Minor version

`runtime.locale.set`

Set the system’s locale. This sets LANG and LC_ALL environment variables to the given value and then calls setlocale. This is set to "C" on startup, which defaults to the system’s default locale. Keep in mind that changing this can potentially impact some functions such a float_of_string.

Type:

(string) -> unit

Arguments:

(unlabeled) (of type string)

`runtime.sys.word_size`

Size of one word on the machine currently executing the program, in bits. Either 32 or 64.

Type:

int

`shutdown`

Shutdown the application.

Type:

(?code : int) -> unit

Arguments:

code (of type int, which defaults to 0): Exit code. Default: 0

`source.is_up`

Check whether a source is up.

Type:

(source('a)) -> bool

Arguments:

(unlabeled) (of type source('a))

Time

`time`

Return the current time since 00:00:00 GMT, Jan. 1, 1970, in seconds.

Type:

() -> float

`time.local`

Convert a time in seconds into a date in the local time zone (current time is used if no argument is provided).

Type:

(?float?) -> unit

Arguments:

(unlabeled) (of type float?, which defaults to null)

Methods:

day (of type int): Day of month.
dst (of type bool): Daylight time savings in effect.
hour (of type int): Hours.
min (of type int): Minutes.
month (of type int): Month of year.
sec (of type int): Seconds.
week_day (of type int): Day of week (Sunday is 0 or 7, Saturday is 6).
year (of type int): Year.
year_day (of type int): Day of year, between 1 and 366.

`time.make`

Convert a date and time in the local timezone into a time, in seconds, since 00:00:00 GMT, Jan. 1, 1970.

Type:

(
 {
   day : int,
   dst : bool?,
   hour : int,
   min : int,
   month : int,
   sec : int,
   year : int
 }) -> float

Arguments:

(unlabeled) (of type { day : int, dst : bool?, hour : int, min : int, month : int, sec : int, year : int })

`time.predicate`

Parse a string as a time predicate

Type:

(string) -> () -> bool

Arguments:

(unlabeled) (of type string)

`time.string`

Obtain a string representation of the current time. It takes a string as argument where special strings are replaced roughly following strftime: %H is replaced by the current hour, %M minute, %S second, %A week day (%a week day abbreviated), %d month day, %B month name (%b month name abbreviated), %z timezone.

Type:

(?time : float?, ?string?) -> string

Example:

s = time.string("Current time is %H:%M.")
print(s)

Example:

# Backup a source naming the file based on time
output.file({time.string("/path/to/file%H%M%S.wav")}, ...)

Arguments:

time (of type float?, which defaults to null): If specified convert the given time (in seconds since 00:00:00 GMT, Jan. 1, 1970) instead of the current time.
(unlabeled) (of type string?, which defaults to null): Description of the string to produce, e.g. "Current time is %H:%M“`.

`time.up`

Current time, in seconds, since the script has started.

Type:

() -> float

`time.utc`

Convert a time in seconds into a date in the UTC time zone (current time is used if no argument is provided).

Type:

(?float?) -> unit

Arguments:

(unlabeled) (of type float?, which defaults to null)

Methods:

day (of type int): Day of month.
dst (of type bool): Daylight time savings in effect.
hour (of type int): Hours.
min (of type int): Minutes.
month (of type int): Month of year.
sec (of type int): Seconds.
week_day (of type int): Day of week (Sunday is 0 or 7, Saturday is 6).
year (of type int): Year.
year_day (of type int): Day of year, between 1 and 366.

`time.zone`

Returns a description of the time zone set for the running process.

Type:

() -> string

Methods:

daylight (of type string): Daylight Savings Time
utc_diff (of type int): Difference in seconds between the current timezone and UTC.

`time.zone.set`

Set the current time zone. This is equivalent to setting the TZ environment variable.

Type:

(string) -> unit

Arguments:

(unlabeled) (of type string)

Track / Audio processing

`track.audio.add`

Mix audio tracks with optional normalization.

Type:

(?id : string?, [pcm('a).{weight? : {float}}], ?normalize : {bool},
 ?power : {bool}) -> pcm('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
(unlabeled) (of type [pcm('a).{weight? : {float}}])
normalize (of type {bool}, which defaults to true): Divide by the sum of weights of ready sources (or by the number of ready sources if weights are not specified).
power (of type {bool}, which defaults to false): Perform constant-power normalization.

`track.audio.amplify`

Multiply the amplitude of the signal.

Type:

(?id : string?, {float}, ?override : string?, pcm('a)) -> pcm('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
(unlabeled) (of type {float}): Multiplicative factor.
override (of type string?, which defaults to "liq_amplify"): Specify the name of a metadata field that, when present and well-formed, overrides the amplification factor for the current track. Well-formed values are floats in decimal notation (e.g. 0.7) which are taken as normal/linear multiplicative factors; values can be passed in decibels with the suffix dB (e.g. -8.2 dB, but the spaces do not matter).
(unlabeled) (of type pcm('a))

`track.audio.clip`

Clip samples, i.e. ensure that all values are between -1 and 1: values lower than -1 become -1 and values higher than 1 become 1. nan values become 0.

Type:

(?id : string?, pcm('a)) -> pcm('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
(unlabeled) (of type pcm('a))

`track.audio.comb`

Comb filter.

Type:

(?id : string?, ?delay : float, ?feedback : {float}, pcm('a)) -> pcm('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
delay (of type float, which defaults to 0.001): Delay in seconds.
feedback (of type {float}, which defaults to -6.): Feedback coefficient in dB.
(unlabeled) (of type pcm('a))

`track.audio.compand`

Compand the signal.

Type:

(?id : string?, ?mu : float, source(pcm('a))) -> pcm('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
mu (of type float, which defaults to 1.)
(unlabeled) (of type source(pcm('a)))

`track.audio.compress`

Compress the signal.

Type:

(?id : string?, ?attack : {float}, ?release : {float}, ?lookahead : {float},
 ?threshold : {float}, ?track_sensitive : bool, ?knee : {float},
 ?pre_gain : {float}, ?gain : {float}, ?ratio : {float}, ?window : {float},
 ?wet : {float}, pcm('a)) -> pcm('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
attack (of type {float}, which defaults to 50.): Attack time (ms).
release (of type {float}, which defaults to 400.): Release time (ms).
lookahead (of type {float}, which defaults to 0.): Lookahead (ms).
threshold (of type {float}, which defaults to -10.): Threshold level (dB).
track_sensitive (of type bool, which defaults to false): Reset on every track.
knee (of type {float}, which defaults to 1.): Knee width (dB).
pre_gain (of type {float}, which defaults to 0.): Pre-amplification (dB).
gain (of type {float}, which defaults to 0.): Post-amplification (dB).
ratio (of type {float}, which defaults to 2.): Gain reduction ratio (reduction is ratio:1). Must be at least 1.
window (of type {float}, which defaults to 0.): RMS window length (second). 0. means peak mode.
wet (of type {float}, which defaults to 1.): How much of input sound to output (between 0 and 1, 0 means only original sound, 1 means only compressed sound).
(unlabeled) (of type pcm('a))

Methods:

gain (of type () -> float): Gain (dB).
rms (of type () -> float): RMS or peak power (linear).

`track.audio.compress.exponential`

Exponential compressor.

Type:

(?id : string?, ?mu : float, pcm('a)) -> pcm('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
mu (of type float, which defaults to 2.): Exponential compression factor, typically greater than 1.
(unlabeled) (of type pcm('a))

`track.audio.map`

Map a function to all audio samples. This is SLOW!

Type:

(?id : string?, ((float) -> float), pcm('a)) -> pcm('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
(unlabeled) (of type (float) -> float)
(unlabeled) (of type pcm('a))

This function is experimental.

`track.audio.stereo.ms.decode`

Decode mid+side stereo (M/S) to left+right stereo.

Type:

(?id : string?, ?width : float, pcm(stereo)) -> pcm(stereo)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
width (of type float, which defaults to 1.): Width of the stereo field.
(unlabeled) (of type pcm(stereo))

`track.audio.stereo.ms.encode`

Encode left+right stereo to mid+side stereo (M/S).

Type:

(?id : string?, pcm(stereo)) -> pcm(stereo)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
(unlabeled) (of type pcm(stereo))

`track.audio.stereo.pan`

Pan a stereo sound.

Type:

(?id : string?, ?pan : {float}, ?field : {float}, pcm(stereo)) -> pcm(stereo)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
pan (of type {float}, which defaults to 0.): Pan ranges between -1 and 1.
field (of type {float}, which defaults to 90.): Field width in degrees (between 0 and 90).
(unlabeled) (of type pcm(stereo))

`track.audio.stereo.width`

Spacializer which allows controlling the width of the signal.

Type:

(?id : string?, ?{float}, pcm(stereo)) -> pcm(stereo)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
(unlabeled) (of type {float}, which defaults to 0.): Width of the signal (-1: mono, 0.: original, 1.: wide stereo).
(unlabeled) (of type pcm(stereo))

`track.audio.stereotool`

Process the given audio track with StereoTool.

Type:

(?id : string?, library_file : string, ?license_key : string?,
 ?preset : string?, ?load_type : string, pcm('a)) -> pcm('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
library_file (of type string): Path to the shared library file.
license_key (of type string?, which defaults to null)
preset (of type string?, which defaults to null): Path to a preset file to load when initializing the operator.
load_type (of type string, which defaults to "totalinit"): Load type for preset. One of: “totalinit”, “all_settings”, “audiofm”, “audio”, “processing”, “repair”, “repair_no_pnr” or “sublevel_pnr”.
(unlabeled) (of type pcm('a))

Methods:

api_version (of type () -> int): API version.
latency (of type () -> float): Get the operator’s latency.
software_version (of type () -> int): Software version.
unlincensed_used_features (of type () -> string?): Check if the license is valid for the current settings.
valid_license (of type () -> bool): Check if the license is valid for the current settings.

`track.audio.stretch`

Slow down or accelerate an audio stream by stretching (sounds lower) or squeezing it (sounds higher).

Type:

(?id : string?, ratio : {float}, pcm('a)) -> pcm('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
ratio (of type {float}): A value higher than 1 means slowing down.
(unlabeled) (of type pcm('a))

`track.decode.audio.pcm_f32`

Decode an audio track using PCM signed 16 bit integers.

Type:

(?id : string?, pcm_f32('a)) -> pcm('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
(unlabeled) (of type pcm_f32('a))

`track.decode.audio.pcm_s16`

Decode an audio track using PCM signed 16 bit integers.

Type:

(?id : string?, pcm_s16('a)) -> pcm('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
(unlabeled) (of type pcm_s16('a))

`track.encode.audio.pcm_f32`

Encode an audio track using PCM signed 16 bit integers.

Type:

(?id : string?, pcm('a)) -> pcm_f32('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
(unlabeled) (of type pcm('a))

`track.encode.audio.pcm_s16`

Encode an audio track using PCM signed 16 bit integers.

Type:

(?id : string?, pcm('a)) -> pcm_s16('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
(unlabeled) (of type pcm('a))

Track / Conversion

`track.audio.mean`

Produce mono audio by taking the mean of all audio channels.

Type:

(?id : string?, ?normalize : bool, pcm('a)) -> pcm(mono)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
normalize (of type bool, which defaults to true): Divide the output volume by the number of channels.
(unlabeled) (of type pcm('a)): Track whose mean should be computed.

`track.audio.stereo`

Convert any pcm audio track into a stereo track.

Type:

(?id : string?, pcm('a)) -> pcm(stereo)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
(unlabeled) (of type pcm('a))

`track.audio.swap`

Swap two channels of a stereo track.

Type:

(?id : string?, pcm(stereo)) -> pcm(stereo)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
(unlabeled) (of type pcm(stereo))

`track.ffmpeg.decode.audio`

Decode a track content

Type:

(?id : string?, ffmpeg.copy('a)) -> pcm('b)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
(unlabeled) (of type ffmpeg.copy('a))

`track.ffmpeg.decode.video`

Decode a track content

Type:

(?id : string?, ffmpeg.copy('a)) -> canvas('b)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
(unlabeled) (of type ffmpeg.copy('a))

`track.ffmpeg.encode.audio`

Convert a track’s content

Type:

(?id : string?, format(audio=pcm('a), 'b), pcm('a)) -> ffmpeg.copy('c)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
(unlabeled) (of type format(audio=pcm('a), 'b)): Encoding format.
(unlabeled) (of type pcm('a))

`track.ffmpeg.encode.video`

Convert a track’s content

Type:

(?id : string?, format(video=canvas('a), 'b), canvas('a)) -> ffmpeg.copy('c)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
(unlabeled) (of type format(video=canvas('a), 'b)): Encoding format.
(unlabeled) (of type canvas('a))

`track.ffmpeg.raw.decode.audio`

Decode a track content

Type:

(?id : string?, ffmpeg.audio.raw('a)) -> pcm('b)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
(unlabeled) (of type ffmpeg.audio.raw('a))

`track.ffmpeg.raw.decode.video`

Decode a track content

Type:

(?id : string?, ffmpeg.video.raw('a)) -> canvas('b)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
(unlabeled) (of type ffmpeg.video.raw('a))

`track.ffmpeg.raw.encode.audio`

Convert a track’s content

Type:

(?id : string?, format(audio=ffmpeg.audio.raw('a), 'b), pcm('c)) ->
ffmpeg.audio.raw('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
(unlabeled) (of type format(audio=ffmpeg.audio.raw('a), 'b)): Encoding format.
(unlabeled) (of type pcm('c))

`track.ffmpeg.raw.encode.video`

Convert a track’s content

Type:

(?id : string?, format(video=ffmpeg.video.raw('a), 'b), canvas('c)) ->
ffmpeg.video.raw('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
(unlabeled) (of type format(video=ffmpeg.video.raw('a), 'b)): Encoding format.
(unlabeled) (of type canvas('c))

Track / FFmpeg filter

`ffmpeg.filter.audio.output`

Return an audio track from a filter’s output

Type:

(?id : string?, ?pass_metadata : bool, ffmpeg.filter.graph,
 ffmpeg.filter.audio) -> ffmpeg.audio.raw('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
pass_metadata (of type bool, which defaults to true): Pass ffmpeg stream metadata to liquidsoap
(unlabeled) (of type ffmpeg.filter.graph)
(unlabeled) (of type ffmpeg.filter.audio)

Track / Track processing

`track.audio.defer`

Defer an audio track by a given amount of time. Track will be available when the given delay has been fully buffered. Use this operator instead of buffer when buffering large amount of data as initial delay.

Type:

(?id : string?, delay : float, ?overhead : float?, pcm_s16('a)) ->
pcm_s16('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
delay (of type float): Duration of the delay, in seconds.
overhead (of type float?, which defaults to null): Duration of the delay overhead, in seconds. Defaults to frame size.
(unlabeled) (of type pcm_s16('a)): Track to delay.

`track.metadata`

Return the metadata associated with the given track

Type:

(?id : string?, 'a) -> metadata where 'a is a track

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
(unlabeled) (of type anything that is a track)

`track.metadata.map`

Rewrite metadata on the fly using a function.

Type:

(?id : string?, (([string * string]) -> [string * string]), ?update : bool,
 ?strip : bool, ?insert_missing : bool, metadata) -> metadata

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
(unlabeled) (of type ([string * string]) -> [string * string]): A function that returns new metadata.
update (of type bool, which defaults to true): Update metadata. If false, existing metadata are cleared and only returned values are set as new metadata.
strip (of type bool, which defaults to false): Completely remove empty metadata. Operates on both empty values and empty metadata chunk.
insert_missing (of type bool, which defaults to true): Treat track beginnings without metadata as having empty ones. The operational order is: create empty if needed, map and strip if enabled.
(unlabeled) (of type metadata)

`track.metadata.merge`

Merge metadata from all given tracks. If two sources have metadata with the same label at the same time, the one from the last source in the list takes precedence.

Type:

(?id : string?, [metadata]) -> metadata

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
(unlabeled) (of type [metadata])

`track.track_marks`

Return the track marks associated with the given track

Type:

(?id : string?, 'a) -> track_marks where 'a is a track

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
(unlabeled) (of type anything that is a track)

Track / Video processing

`ffmpeg.filter.video.output`

Return a video track from a filter’s output

Type:

(?id : string?, ?pass_metadata : bool, ffmpeg.filter.graph,
 ffmpeg.filter.video) -> ffmpeg.video.raw('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
pass_metadata (of type bool, which defaults to true): Pass ffmpeg stream metadata to liquidsoap
(unlabeled) (of type ffmpeg.filter.graph)
(unlabeled) (of type ffmpeg.filter.video)

`track.video.add`

Merge video tracks.

Type:

(?id : string?, [canvas('a)]) -> canvas('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
(unlabeled) (of type [canvas('a)])

`track.video.add_image`

Add a static image on the given video track.

Type:

(?id : string?, ?fallible : bool, ?width : {int}?, ?height : {int}?,
 ?x : {int}, ?y : {int}, file : {string}, canvas('a)) -> canvas('a)

Arguments:

id (of type string?, which defaults to "track.video.add_image"): Force the value of the source ID.
fallible (of type bool, which defaults to false): Whether we are allowed to fail (in case the file is non-existent or invalid).
width (of type {int}?, which defaults to null): Scale to width
height (of type {int}?, which defaults to null): Scale to height
x (of type {int}, which defaults to 0): x position.
y (of type {int}, which defaults to 0): y position.
file (of type {string}): Path to the image file.
(unlabeled) (of type canvas('a))

`track.video.tile`

Tile video tracks.

Type:

(?id : string?, ?proportional : bool, [canvas('a)]) -> canvas('a)

Arguments:

id (of type string?, which defaults to null): Force the value of the track ID.
proportional (of type bool, which defaults to true): Scale preserving the proportions.
(unlabeled) (of type [canvas('a)])