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Lost audio/video sync

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Topic starter

Hi, I'm new to Cinelerra. I have been editing some live capture footage with audio and I realized that the audio of one channel got out of sync with the video and other audio channel. E.g. I see that the video clip has a StartSource of 0:01:07:28 and the audio is at 0:01:17:15. How do I restore the sync? 

I read the previous post about linking audio and video, but the damage is done and I may need to resync A/V in several clips without having to re-insert them from the source.

Thanks.

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@scossu

How do I restore the sync?

The correct solution that I know of is to redo your project.

Or else you could make a mistake and lose all of your hard work.

I will send you email on a NOT RECOMMENDED one time use workaround.  It would be at your sole risk.

UPDATE: email bounced; will try again.

 

This post was modified 1 week ago by phylsmith2004
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Is the gap the same for all the edits or different for any edits?

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Topic starter

The gap is different for many edits. For now I have been painstakingly looking at the timecode for the video track, comparing the timecode of each audio track of each clip, and adjusting via rolling and sliding. It would be immensely helpful to have a function to do this automatically, since especially with newbies or pros used to different tools, it's very easy to forget that audio and video tracks are not ganged by default and shift one by mistake (and then realizing hundreds of edits later). 

Thanks for the suggestions.

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If one Audio channel is in sync with the video correctly you could use a (my) workaround with InterView feature.
I could make a demo for you but without texts; and I don't know if it may be clear for you.
Maybe, You could see that demo tomorrow (?) and I don't know if it will be too late for you.

PS: Consider I have a lot of problem with Forum. I can see your post (with login) after 24 hours. Probably it depends by my System. I don't know.

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Topic starter

Hi, thanks for offering to demo your solution. 

I actually managed to get the tracks back in sync with the manual method I described before. It took  me half a day. I'd still be interested in seeing your  solution, however my tacks were badly misaligned both in source and timeline points. 

I found out how I got the alignment messed up: if you gang tracks of which some are  armed, some not, you will only see if the master track is armed. So, if a hidden/ganged track is armed and the master is not, or vice versa, if you make edits the tracks will fall out of sync. 

I think that the ganging function should be reviewed or at least a caveat should be added in the documentation to avoid this scenario. It would be best if when ganging, the non-master tracks are set to the same arming setting of the master, and as long as they are ganged, they follow the arm/disarm toggles applied to the master. This would make it less likely to make my mistake.

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@scossu

Uh, oh!! I think you found a bug because when I started to put your suggested caveat in the manual I found this Note already there.

When in Gang Channels or Gang Media mode, if the first audio track is not disarmed, but any of its connected channel tracks are, the disarm of those channels are ignored and all channels are treated as being armed. This is to be consistent with the purpose of using this mode; the purpose being that any edits to the first master track are automatically propagated to all other channels.

Thank you very much for following up on this forum thread so we now know how you got the unalignment problem.  I am going to check previous versions of CinGG to see where the bug creeped in and will add a Bug Tracker request to get this fixed if possible.  If it can not be fixed for some reason, the manual will have to be fixed instead to warn others.

      https://www.cinelerra-gg.org/bugtracker/view.php?id=577

@IgorBeg

Yes, please, do a demo as I had forgotten about Interview mode providing a way to more easily get things lined back up as it was not really meant for that.  But a long time ago, when testing the Interview code an easy way to make sure it was working right was to be everything back to the original media.  (I am going to add this to the manual as a usage for Interview mode !)

This post was modified 7 days ago 2 times by phylsmith2004
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Found it.

I am going to check previous versions of CinGG to see where the bug creeped in and will add a Bug Tracker request to get this fixed if possible.

The bug creeped into the code in the 10/31/2020 release when modifications were made to accommodate some needed aspects of Gang Mode.  Unfortunately, as usual it may not be easy to find and fix the problem.

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I'd still be interested in seeing your solution

Okay. My really ugly screencast (in my old way) "Using the InterView Mode to rebuild the Timeline from a lost Audio Channel" at:
https://streamable.com/695jrb
May be it was no good for your problem.

About Gang Modes bug.
Mmmh, it is strange,... it works right in the CinelerraGG_20200930 release, anymore since Cinelerra_20201031 release.

@scossu
If you want to test the CinelerraGG_20200930 release You can download it from:
https://cinelerra-gg.org/download/old_tars/

@phylsmith2004
Knowing you are a great expert (Developer) in Linux-OS, Git, Diff, and so on,
and you can read the code, could you compare the two releases, please? I hope you may find and fix the problem. Thank you!

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