ReadonlykindReadonlyregionOptional ReadonlycoverageOptional semantic coverage that removes pixels outside the source shape.
Optional ReadonlyeffectOptional bounded effect applied before the media crop is composited.
The browser backend samples the renderer-owned media texture and keeps its filters, render targets, and coverage artifacts private. An effect never creates a second decoder or copies the composited canvas through the CPU.
Reuses pixels from the renderer-owned media frame.
The source region is resolved from the same semantic detection as the destination region. Browser backends crop the already-presented media texture; they must not create another decoder or expose that texture.