Version: 2.2.5

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?, ?assume_autocue : bool?, ?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.
assume_autocue (of type bool?, which defaults to null): Assume that a track has autocue enabled when all four cue in/out and fade in/out override metadata are present. Defaults to settings.crossfade.assume_autocue when null.
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,
 ?initial_fade_in_metadata : [string * string],
 ?initial_fade_out_metadata : [string * string], 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.
initial_fade_in_metadata (of type [string * string], which defaults to []): Initial fade-in metadata
initial_fade_out_metadata (of type [string * string], which defaults to []): Initial fade-out metadata
(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)),
 ?assume_autocue : bool?, ?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).
assume_autocue (of type bool?, which defaults to null): Assume that a track has autocue enabled when all four cue in/out and fade in/out override metadata are present. Defaults to settings.crossfade.assume_autocue when null.
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, ?delay : float, ?curve : float?,
 ?override_duration : string, ?override_type : string,
 ?override_curve : string, ?override_delay : string,
 ?persist_overrides : bool, ?track_sensitive : bool,
 ?initial_metadata : [string * 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 and a set of internal tracks

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.
delay (of type float, which defaults to 0.): Initial delay before starting fade.
curve (of type float?, which defaults to null): Fade curve. Default if null.
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_in_type"): Metadata field which, if present and correct, overrides the 'type' parameter for the current track.
override_curve (of type string, which defaults to "liq_fade_in_curve"): Metadata field which, if presents and correct, overrides the curve parameter for the current track. Use "default" to set to default value.
override_delay (of type string, which defaults to "liq_fade_in_delay"): Metadata field which, if presents and correct, overrides the initial fade delay.
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 false): Be track sensitive (if false we only fade in once at the beginning of the track).
initial_metadata (of type [string * string], which defaults to []): Initial metadata.
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 and 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.
fade_delay (of type () -> float):
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, ?delay : float, ?curve : float?,
 ?override_duration : string, ?override_type : string,
 ?override_curve : string, ?override_delay : string,
 ?persist_overrides : bool, ?track_sensitive : bool,
 ?initial_metadata : [string * 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.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.
delay (of type float, which defaults to 0.): Initial delay before starting fade.
curve (of type float?, which defaults to null): Fade curve. Default if null.
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_out_type"): Metadata field which, if present and correct, overrides the 'type' parameter for the current track.
override_curve (of type string, which defaults to "liq_fade_out_curve"): Metadata field which, if presents and correct, overrides the curve parameter for the current track. Use "default" to set to default value.
override_delay (of type string, which defaults to "liq_fade_out_delay"): Metadata field which, if presents and correct, overrides the initial fade delay.
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 false): Be track sensitive (if false we only fade ou once at the beginning of the track).
initial_metadata (of type [string * string], which defaults to []): Initial metadata.
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:

(?curve : float?, ?type : string, ?start : float, ?stop : float,
 ?delay : float, ?duration : float, ?on_done : (() -> unit), source('a)) ->
() -> float

Arguments:

curve (of type float?, which defaults to null): Fade curve for "log" and "exp" shapes. If null, depends on the type of fade. The higher the value, the shaper the curve.
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.
delay (of type float, which defaults to 0.): Initial delay before starting fade.
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))

cross​

cross.simple​

cross.smart​

crossfade​

fade.in​

fade.out​

mkfade​

`cross`

`cross.simple`

`cross.smart`

`crossfade`

`fade.in`

`fade.out`

`mkfade`