Sine

Audio Single output Source

Generate sine wave audio signal.

FFmpeg filter: sine — the official reference.

Generate a stream. Sine is a source — it has no input, so you create a stream from it rather than applying it to one:

$audio = \FFmpeg\AudioStream::generate(new Sine(…));

apply() and addFilter() do not apply to source filters (there is nothing to attach them to).

When to use it

TODO — when this filter shines: what it’s the right tool for, what to reach for instead when it isn’t, and how it composes with neighbouring filters.

How to use it

TODO — prose: how the filter actually works and what its key parameters mean (the explanation FFmpeg’s terse option help omits).

Examples

TODO — runnable PHP, with the equivalent ffmpeg CLI alongside.

Gotchas

TODO

See also

TODO

Parameters

Parameter	Type	Default	Range / values	Description
frequency	float	440	≥ 0	set the sine frequency
beep_factor	float	0	≥ 0	set the beep frequency factor
sample_rate	int	44100	≥ 1	set the sample rate
duration	int	0	≥ 0	set the audio duration
samples_per_frame	string	1024	—	set the number of samples per frame

FFmpeg also names these options (use the parameter shown above): f → frequency, b → beep_factor, r → sample_rate, d → duration.

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Maps to FFmpeg’s sine filter. Verified against ffmpeg n7.1.1.