Fftfilt

Video Single output Transform

Apply arbitrary expressions to pixels in frequency domain.

FFmpeg filter: fftfilt — 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():

$node   = $video->addFilter(new Fftfilt(…));
$result = $node->outputs()[0];

Shorthand. Single-output filters can skip the node — apply() returns the result stream directly:

$result = $video->apply(new Fftfilt(…));

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
dc_Y	int	0	0–1000	adjust gain in Y plane
dc_U	int	0	0–1000	adjust gain in U plane
dc_V	int	0	0–1000	adjust gain in V plane
weight_Y	string	1	—	set luminance expression in Y plane
weight_U	string	—	—	set chrominance expression in U plane
weight_V	string	—	—	set chrominance expression in V plane
eval	FftfiltEval	init	init, frame	specify when to evaluate expressions

---

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