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#596 Adjusting the delay when extracting MKV audio
Could the audio delay detected by MeGUI for MKVs be adjusted accordingly if there's also a video delay?
gMKVExtractGUI has done so for a while as does the current version of MKVCleaver (although I'm not sure if the way it does so is the best method).
There's possibly no way to adjust the audio delay that's correct for all scenarios, but based on the assumption the video will be re-encoded, the video delay should probably be assumed to be zero and the audio delay adjusted if necessary.
Video delay 50ms, Audio delay, 100ms, Delay written to extracted audio +50ms
Video delay 100ms, Audio delay, 50ms, Delay written to extracted audio -50ms
The "extracted audio" delay above would be the audio delay displayed by the MediaInfo.GUI.
If the extracted audio delay is negative it's a sure sign there's a video delay in the source file, but it's impossible to tell when the extracted audio delay is positive, so maybe MeGUI could add something like [V] to the file name of the extracted audio to indicate there was a video delay? When re-encoding the video it doesn't matter, but if you happen to be re-encoding just the audio and remuxing it with source video, you'd need to know to apply the original audio delay, not the "extracted" delay.
could you please provide a sample for this? this would make it easier for me to check / work on it.
Hi Zathor.
Sorry about being slow.... I forgot.... but attached is a zip file containing 4 tiny MKVs with various audio and video delays along with a text file explaining my thoughts on determining the audio delays when extracting. Hopefully I got them right.
Thanks.