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Old 05-15-2019, 06:54 AM
Leverson Leverson is offline
Join Date: Aug 2011
Location: Los Angeles
Posts: 141
Default Re: Importing 16 bit audio from video to a 24bit session is 1/4 frame early

What kinds of video codecs are you receiving? And what kind of audio with them? I find that often when I receive H.264 video encodes they are about a quarter frame off sync with the guide audio. Even if I reconvert to ProRes the offset remains. I had assumed it was a factor in the H.264 encoding process as it's an inter frame codec and things get sloppy, or part of the AAC or mp3 audio convert that tends to go along with them. I've never thought to test to see if bit rate is also a factor.

Either way, good rules of thumb are 1.) trust the sync of the AAF/OMF audio over the video reference guide track, and 2.) When head and tail pops are exactly a frame just slip the video guide audio track over until the beep boundaries are back to exactly within the frame alignment again.
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