Acrossover

Audio Multiple outputs Transform

Split audio into per-bands streams.

FFmpeg filter: acrossover — the official reference.

Add it to a graph. The explicit form works for every filter — bind it to its input and read the result from outputs():

$outputs = $audio->addFilter(new Acrossover(…))->outputs(); // one stream per output pad

Shorthand. Not available — apply() returns a single stream, and Acrossover has multiple outputs. Use addFilter() + outputs() above.

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
split	string	500	—	set split frequencies
order	AcrossoverM	4th	2nd, 4th, 6th, 8th, 10th, 12th, 14th, 16th, …	set filter order
level	float	1	0–1	set input gain
gain	string	1.f	—	set output bands gain
precision	AcrossoverPrecision	auto	auto, float, double	set processing precision

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