getPresentationTimeStamp
Client callback that returns a CMTime from a CMBuffer.
Declaration
var getPresentationTimeStamp: CMBufferGetTimeCallback?Discussion
This callback is called from once CMBufferQueueGetFirstPresentationTimeStamp(_:) and multiple times from CMBufferQueueGetMinPresentationTimeStamp(_:).
It should return the presentation timestamp of the buffer. If there are multiple samples in the buffer, this callback should return the minimum presentation timestamp in the buffer.
This can be NULL (CMBufferQueueGetFirstPresentationTimeStamp(_:) and CMBufferQueueGetMinPresentationTimeStamp(_:) will return kCMTimeInvalid).