addMutableTrack(withMediaType:preferredTrackID:)
Adds an empty track to a composition.
Declaration
func addMutableTrack(withMediaType mediaType: AVMediaType, preferredTrackID: CMPersistentTrackID) -> AVMutableCompositionTrack?Parameters
- mediaType:
The media type of the new track.
- preferredTrackID:
The preferred track ID for the new track. The system generates a unique ID if the value you specify isn’t available. If you don’t need to specify a preferred track ID, pass Kcmpersistenttrackid_invalid, and the system generates an appropriate identifier.
Return Value
A new mutable composition track.