Global Variable


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


const AVTrackAssociationType AVTrackAssociationTypeSelectionFollower;


An association from one track to another specifying that when the user selects the first track, the second should be considered an appropriate default selection. For example, a follower for an audio track could be a subtitle track in the same language. When the user chooses a language for audio, the subtitle language “follows” the audio language selection.

See Also

Track Association Types


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


The associated track contains chapter information for the base track.


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


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


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

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