Audio from OMF slightly out of sync with audio from MP4

Nuendo
#1

Hey all, has anybody else had this issue?

After importing the OMF (also happens with AAF), I compare the audio to see if it sync’s with the audio that comes with the MP4 (after importing the MP4). All of the audio is a couple of frames out of sync.

If this is a common thing (maybe because of e.g. FCP), then do I shift everything to try and line it up with the audio from the MP4 or do i leave it as is, final mix it and then send back to the editor who will insert back into their project and it will somehow line up again?

#2

There are only a couple of video codecs that guarantee frame-accurate sync. (Not only in Nuendo, in any application)
Avid Dndx, Apple Prores and PhotoJpeg.
Anything else is a no-go. in fact, those ti,y mp4’s are the worse of all. The more compression the worse sync is.
Ask the video editors for a properly encoded video and check again.

Fredo

#3

Fredo’s answer is spot on, MP4’s are horrible. I’m on Mac and use Compressor or QT Pro 7 to transcode to ProRes or PJpeg. john

#4

Ok cool thanks. So would you say that if the editor is unable to supply a higher quality video like the ones you mentioned, would you say its best to not shift the audio from the OMF to match up with the MP4’s audio as it will correlate once mixed and sent back to the editor?

#5

Unable to deliver anything better?
Please try to convince your monther-in-law to stick to knitting.

There are procedures in audio post, and by extention for eveybody working in Picture & sound.
Always ask for properly encoded video, BITC and at least one 2pop.
Without these minimum requirements it is a hit-and miss and no-one can guarantee anything. It’s guess-work.

The only thing you can do is tryint to sync the audio manually to the video.
Search for a doorslap, a footstep, something that is clearly visible in audio & video, and line them up.
That being said, with an mp4, you won’t be able to line them up. There will alwyas be a couple-of-frames grey area.

Fredo