[LAU] OT - syncing partially out of sync video and audio in existing files

[Renato]

On Fri, 10 Jun 2011 17:58:46 +0200
Philipp <hollunder at lavabit.com> wrote:

> Hi,
> sorry for abusing this list for a mostly video editing question, but I
> didn't find a proper list and knew that we have some video people on
> this list.
> 
> I'd like to fix some videos that have partially out of sync video and
> audio, meaning that beginning at a certain point in the video the
> audio is suddenly out of sync by a couple of seconds. There's no
> constant change, the delay seems fixed once it's there.
> 
> I wonder how to fix such a thing. The files are xvid encoded videos
> and vbr mp3 audio inside avi containers. I thought it should be
> reasonably easy to cut and move the audio (re-encode if unavoidable,
> but I know it's in principle possible without) and put it back in a
> container, but I didn't manage.
> 
> Can someone recommend a program/workflow that would allow this?
> 
> I tried:
> - Avidemux: seems like actual editing is not what this program was
>   written for, couldn't figure it out, but it seems close
> 
> - openshot: couldn't figure out how to separate video/audio
> 
> - kino: seems to only work with DV-files, apparently takes ages to
>   decode the file, doesn't seem to be what I need
> 
> - openmovieeditor: I figured it might work by dragging the file to
> both a video and an audio track, but I got extremely garbled audio
> output, no idea what's wrong
> 
> - cinelerra-cv: Doesn't start. No error message, it simply shows no
>   window, nothing. Well, it does something with the screen, but it
> shows nothing.
> 
> - pitivi: Doesn't seem like it can play back the video. I can drag the
>   video to the tracks and it starts to draw a waveform, I guess no
> video thumbnails because of: gst.ElementNotFoundError: pngenc
>   Doesn't seem to be able to play the video.
> 
> - kdenlive: would require me to install 30 additional packages, total
>   about 200MB, no thanks.
> 
> I thought it would be a simple task, really nothing fancy. Seems like
> I was wrong.
> 
> Regards,
> Philipp
> 

Hi, unfortunately can't give you a full solution, but only a hint: in
mplayer with "-" and "+" you can adjust audio/video syncronization by
multiples of 100ms (maybe you cand do finer, but I'm not sure). 

maybe you could then somehow record the output to a new file?

cheers
renato