Essential snippet for decompressing sample into CVImageBufferRef

FXDsampleBufferDecompressing.m

{
	CMFormatDescriptionRef formatDescription = CMSampleBufferGetFormatDescription(compressedSample);


	static VTDecompressionSessionRef decompressionSession;

	if (decompressionSession == NULL) {
		VTDecompressionSessionCreate
		(NULL,
		 formatDescription,
		 NULL,
		 NULL,
		 NULL,
		 &decompressionSession);
	}


	VTDecompressionSessionDecodeFrameWithOutputHandler
	(decompressionSession,
	 compressedSample,
	 kVTDecodeFrame_EnableAsynchronousDecompression,
	 NULL,
	 ^(OSStatus status,
	   VTDecodeInfoFlags infoFlags,
	   CVImageBufferRef  _Nullable imageBuffer,
	   CMTime presentationTimeStamp,
	   CMTime presentationDuration) {

		 //MARK: New CMSampleBufferRef may have to be created for other uses
	 });
}