An object that represents an immutable video composition.
- iOS 4.0+
- macOS 10.7+
- Mac Catalyst 13.0+
- tvOS 9.0+
The AVFoundation framework also provides a mutable subclass,
AVMutable, that you can use to create new videos.
A video composition describes, for any time in the aggregate time range of its instructions, the number and IDs of video tracks that are to be used in order to produce a composed video frame corresponding to that time. When AVFoundation’s built-in video compositor is used, the instructions an
AVVideo contain can specify a spatial transformation, an opacity value, and a cropping rectangle for each video source, and these can vary over time via simple linear ramping functions.
You can implement your own custom video compositor by implementing the
AVVideo protocol; a custom video compositor is provided with pixel buffers for each of its video sources during playback and other operations and can perform arbitrary graphical operations on them in order to produce visual output.