Source / Sound synthesis

dtmf

Generate DTMF tones.

Type:

(?duration : float, ?delay : float, string) -> source(audio='a)
where
  'a is a track of type: pcm, pcm_s16 or pcm_f32 and a track of type: pcm, pcm_s16, pcm_f32, canvas, metadata or track_marks

Arguments:

• duration (of type float, which defaults to 0.1): Duration of a tone (in seconds).
• delay (of type float, which defaults to 0.05): Dealy between two successive tones (in seconds).
• (unlabeled) (of type string): String describing DTMF tones to generates: it should contains characters 0 to 9, A to D, or * or #.

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.

metronome

Indicate beats.

Type:

(?frequency : float, ?float) -> source(audio=pcm('a))

Arguments:

• frequency (of type float, which defaults to 440.): Frequency of the sound.
• (unlabeled) (of type float, which defaults to 60.): Number of beats per minute.

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.