Filters

A first-class filter graph API: every FFmpeg filter as a typed PHP class, with one documentation page each — parameters, runnable PHP, the equivalent ffmpeg CLI, gotchas, and a live in-browser playground.

How a filter attaches

A filter transforms a stream and returns a new one. The whole catalog is reachable as Filter classes, and the friendly methods and apply() are sugar over one canonical path: a FilterNode binds a filter to its input streams, and you read its results with outputs().

$clip->scale(1280, 720);                       // friendly method — sugar
$clip->apply(new \FFmpeg\Filter\Vignette());   // any filter, by its 1:1 class — also sugar

Concretely, $clip->apply($f, ...$extra) is exactly $clip->addFilter($f, $extra)->outputs()[0]: build the node, return its sole output. Nothing has privileged access — the convenience layer goes through the same door you can use directly.

Parameters can be a number, an FFmpeg expression string, or a PHP closure run per frame — and a bad expression is caught the instant you construct the filter. See the Architecture for the model behind all of it.

One output, or many

A Filter is just configuration; the wiring is a separate, immutable FilterNode that binds the input streams (input 0 first, more for multi-input filters) and exposes the results by pad.

Most filters have a single output, so apply() hides the node and returns that one output — taking extra inputs positionally for multi-input filters like overlay:

$bg->apply(new Overlay(x: 10, y: 10), $logo);   // 2 inputs → 1 output

A filter with several outputs — split — is built as a node, stream-first with addFilter() or directly with new FilterNode(...), and you read its outputs by pad index. Each output is a normal stream, so you can process the branches independently and recombine them:

[$a, $b] = array_values($clip->addFilter(new Split(2))->outputs());  // [0 => …, 1 => …]
$thumb   = $b->apply(new Scale(160, 120));
$result  = $a->apply(new Overlay(x: 10, y: 10), $thumb);             // recombine the branches

apply() accepts only single-output filters, so $clip->apply(new Split(2)) is a type error — and if one slips past the types, the exception says so plainly: “Split has multiple outputs — build it with addFilter() and read outputs(), not apply().”

Browse by kind

• Sources — synthesize a stream from nothing (color, bars, tones, silence)
• Audio — transform an audio stream (loudness, mixing, dynamics, fades)
• Video — transform a video stream (scale, crop, overlay, text)

Try the playground

You can already feel the filters in the Playground — tweak parameters and see real FFmpeg (compiled to WebAssembly) filter a sample frame live in your browser, with the PHP and ffmpeg CLI generated as you go.

Note

Want to help get there sooner? Sponsor the project — and support FFmpeg too.

Every filter page follows one strict template — parameter table, examples, gotchas, FFmpeg provenance — so the catalog stays consistent across hundreds of filters.