Fixing A/V sync of single reel DCPs with a small VF
Posted: Wed May 24, 2023 11:23 am
From time to time I encounter DCPs with audio and video out of sync.
Currently I am making a VF referencing only the video content and generating a new audio MXF.
For ease of distribution, it would however be nice if I was allowed to fix the A/V sync by referencing the audio file as well and adjusting the delay in the content audio tab.
That way the VF would only contain references to the original video and audio files, and only a new XML structure would have to be distributed.
I imagine that this could be accomplished by changing the <EntryPoint> and <Duration> of the reel specification in the CPL.
This would limit the granularity of the delay to numbers of whole frames, but I guess that this is sufficient.
I am aware that this trick probably only would be applicable to single reel DCP's to avoid loosing audio or video at reel transitions.
So is there a way to make DCP-o-matic (GUI or CLI) generate a new set of XML's referencing the original video and audio MXFs and adjust the entry point and duration specified in the CPL?
Cheers,
Christian
Currently I am making a VF referencing only the video content and generating a new audio MXF.
For ease of distribution, it would however be nice if I was allowed to fix the A/V sync by referencing the audio file as well and adjusting the delay in the content audio tab.
That way the VF would only contain references to the original video and audio files, and only a new XML structure would have to be distributed.
I imagine that this could be accomplished by changing the <EntryPoint> and <Duration> of the reel specification in the CPL.
This would limit the granularity of the delay to numbers of whole frames, but I guess that this is sufficient.
I am aware that this trick probably only would be applicable to single reel DCP's to avoid loosing audio or video at reel transitions.
So is there a way to make DCP-o-matic (GUI or CLI) generate a new set of XML's referencing the original video and audio MXFs and adjust the entry point and duration specified in the CPL?
Cheers,
Christian