Timecode out by 12 frames - Batch fix?

A

analog_addict

Well-known member
Hello,

Just worked on a project and the sound recordist forgot to sync the tentacle timecode boxes correctly on the second day.

So every clip from day 2 has the audio out by 12 frames. I used Tentacle Sync Studio to sync up.

Has this happened to anyone before and is there a batch software where I can shift all the audio forward by 12 frames without re-encoding? Like how Tentacle Sync doesn't re-encode the video/audio.

Thanks!
 
Audio clips can easily be shifted in just about any NLE. Some offer sub-frame resolution. In Vegas Pro for instance, audio can moved down to the sample level. With LTC, we used to be able to enter an offset in the reader. On the other hand SD's Wave Agent allows changing the TC stamp.
 
Rick pretty much nailed it. If you are trying to re-stamp the files to the correct time then WaveAgent can do that. To be of any use in post though you would need to be very accurate in the offset. Somehow an even 12 frames seems unlikely and 1/2 frame out is WAY out for dialog. Re-stamping is just rewriting some header info and doesn't change the audio at all. Assuming you have WAV or AIFF files there would be no encoding to redo anyway.

But if you don't have an exact offset (to the subframe level) then it's probably not a good idea to change the time stamp. At 12 frames it will be really obvious down the line and the sound post people can sync it up just send a note explaining it's about 12 frames out. If you re-stamp it you will be within a frame of dead sync and it may not be obvious to say picture editors and post sound will get a bit of a mess. This used to happen on the DX100 (the early models had a 1 1/4 frame offset over firewire). Editors would catch some clips and "fix" them and others would be off. So in sound post you get this mess where all the clips need to be nudged but all by different amounts. Trust me it is MUCH preferred to have all the production off by the same amount.

If this is not going to sound post I would still leave them off and have the editor use something like PluralEyes to sync them to the guide track. Manually re-syncing in a NLE is problematic because very few of them let you easily work at a subframe level so you end up with the same problem as re-stamping with out the subframe info.
 
Wave agent can change the time stamp, but it can't batch process a whole bunch of files. I just confirmed this with Sound Devices. I don't know of anything that can batch process new timecode stamps like that.

The few times I've had to fix an issue like that I've manually copied and pasted the time stamps from the picture files into the metadata of the audio files. I used Sound Hack for this (back before Wave Agent existed). I was doing this as a trouble shooting method for a customer and I handed the files off. I didn't hear any complaints so when I followed up to see if it worked they said it did. It was only for one day of shooting on a feature, and there weren't a ton of takes, so it didn't take me a ton of time.
 
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