Select

Video Multiple outputs Transform

Select video frames to pass in output.

FFmpeg filter: select — 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 = $video->addFilter(new Select(…))->outputs(); // one stream per output pad

Shorthand. Not available — apply() returns a single stream, and Select 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
expr	string	1	—	set an expression to use for selecting frames
outputs	int	1	≥ 1	set the number of outputs

FFmpeg also names these options (use the parameter shown above): e → expr, n → outputs.

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