Type Alias


Prototype for the block invoked when frame compression is complete.


typealias VTCompressionOutputHandler = (OSStatus, VTEncodeInfoFlags, CMSampleBuffer?) -> Void



noErr if compression was successful; an error code if compression was not successful.


Contains information about the encode operation.

The asynchronous bit may be set if the encode ran asynchronously.

The frameDropped bit may be set if the frame was dropped.


Contains the compressed frame if compression was successful and the frame was not dropped; otherwise, NULL.


When you encode a frame, you pass in a callback block to be called for that compressed frame. This block is called in decode order (which is not necessarily the same as display order).

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