Type Property


The track contains the same content as another track, but in a more widely supported format.


static let audioFallback: AVAssetTrack.AssociationType


A player that does not support the format of the original track can use the fallback track instead. For example, an asset may contain both stereo and a 5.1-channel audio tracks. In this case, marking the stereo track as the fallback for the 5.1-channel track would ensure that devices not capable of playing 5.1-channel audio can still play an equivalent track.

See Also

Track Association Types

static let chapterList: AVAssetTrack.AssociationType

The associated track contains chapter information for the base track.

static let forcedSubtitlesOnly: AVAssetTrack.AssociationType

The subtitle track containing forced and non-forced subtitles is associated with a subtitle track containing only forced subtitles.

static let metadataReferent: AVAssetTrack.AssociationType

The metadata track is associated with the track being described or annotated.

static let selectionFollower: AVAssetTrack.AssociationType

The second track in the association is considered an appropriate default for the first track.

static let timecode: AVAssetTrack.AssociationType

The track is associated with a timecode track containing timing information for the original track.