AVI conversion, audio sync problem

[Dragonsf]

what kind of avi is this? which codec?

[guns1inger]

Use the latest g-spot to confirm the video and audio formats. If the audio is VBR mp3, try saving as an uncompressed wav file using virtualdubmod, the using this as the audio track.

Actually, at this stage I would try going the uncompressed wav route. If the audio isn't VBR MP3 then it seems to have some corruption that is through out the sync. You need to accept though that sometimes you download crap, and it can't be fixed.

[nicke1]

Hi

I've got an avi file (350mb) which I want to convert to DVD (vob) so I can watch it on my standalone DVD player.

I've previously converted avi's using NeroVision Express without any problems.

With this particular avi after about 4 minutes in, the audio becomes out-of-sync by about .75 to 1 second. This renders the DVD unwatchable. The avi plays perfectly on my PC without any sync issues.

I've tried the fix program mentioned on these forums but it didn't help.

Presumably there is some type of problem with the avi that the windows media player copes with but manifests itself when using a conversion program.

Is there any simple way to resolve the sync issue to get a working DVD copy? I don't want to spend hours on this (or with future avi's) since another option, less prefered, is to simply take my laptop through to where the TV is and play the avi and output to the TV.

Thanks
Nick

[nicke1]

I'm at the work at the moment so can't give precise details from gspot.

But from file properties (summary) the video is XVID and the audio MPEG-Layer3

I've tried using Nerovision to export the avi to a new format of avi with the audio uncompressed and I get the same problem. I've also tried exporting to MPEG2 for the video and no compression for the audio and both still have problems at exactly the same spot.

The thing I don't understand is - if there is a problem with the file then why can media player perfectly run the avi but a conversion program introduce the sync problem.

[mats.hogberg]

The thing I don't understand is - if there is a problem with the file then why can media player perfectly run the avi but a conversion program introduce the sync problem.

That's how it works. A player can gracefully "gloss over" bad spots. An encoder can't - it want each and every frame of the source, or it will go haywire. I suspect the source AVI is corrupt (has undecodable/bad frames) at the spot where you get the sync problem.
If you load it in VirtualDubMP3Freeze and scan it for errors, does it report any?

/Mats

[nicke1]

Thanks for the explanation on how the players and encoders differ.

I tried the check for errors facility in VirtualDubMP3Freeze and it didn't report any bad frames.

I think given the out of sync always occurs at the same place regardless of whether I convert to another AVI, MPEG2, DVD, etc. there must be something wrong with the file.

Are there any other encoders that may handle the assumed problem better than NVE?

[mats.hogberg]

I suspect all encoders will choke at the same spot. But regardless, I wouldn't recommend NVE at all - take a look at AVI to MPG/DVD left, and encoders under tools for a selection of other encoders to try. TMPGEnc, ManiConcept, CCE, free quEnc... There are many options.

What you could try, is:
1)As VDubMP3Freeze sees no problems, sav out a new version of the AVI, using direct stream copy for both a+v. Then try reencoding this AVI.
2)Try a newer or different codec. Update to latest version, or try another build of the same, or try using ffdshow.

/Mats