Instance Property


The master clock used for item time bases.


var masterClock: CMClock? { get set }


The default value of this property is NULL, which means that the master clock is automatically chosen. When non-NULL, this property overrides the automatic choice of master clock for item timebases. This is most useful when you are synchronizing video-only movies with audio played by another source.

See Also

Synchronizing Playback to an External Source

func setRate(Float, time: CMTime, atHostTime: CMTime)

Synchronizes the playback rate and time of the current item with an external source.

func preroll(atRate: Float, completionHandler: ((Bool) -> Void)?)

Begins loading media data to prime the media pipelines for playback.

func cancelPendingPrerolls()

Cancels any pending preroll requests and invokes the corresponding completion handlers if present.

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