Audio gets out of sync with VirtualDub

[jeffareid]

I used DVD decrypter to transfer a VOB file from a DVD to a hard drive.

I can play the VOB file with PowerDVD, and the audio stays in sync.

When I use VirtualDub to open the VOB file it opens up a warning box with a lot of messages stating: "Anachronistic or discontinous timestamp found in audio stream 29 at byte position xxxxxxxx (may indicate improper join)."

Then when I then try to play or convert the VOB file, the audio gets out of sync, steadily getting worse as the video is played or converted. However, as mentioned, PowerDVD plays the VOB file just fine without any loss of sync between video and audio.

Am I doing something wrong?

So far the only method that works is to use fraps to capture video and sound while playing the VOB file with PowerDVD.

Different programs also report different frame rates for the save VOB file, I see 23.976 and 29.97 reported on the same VOB file.

[setarip_old]

Hi!

Once you've converted the file to (presumably) .DivX-compressed or XviD-compressed .AVI format:

A) If the difference between audio and video is constant throughout the video:

Load the file into VirtualDub, VirtualDubMod, or NanDub.
Set BOTH "Video"(VirtualDub, VirtualDubMod and NanDub) and "Audio" (VirtualDub and NanDub - VirtualDubMOD>"Streams>"Stream list") to "Direct Stream Copy".
From the "Audio" dropdown menu, select "Interleaving" (For VirtualDubMOD, rightclick on the listed audiostream and then select "Interleaving")
Under "Audio skew correction", set an appropriate number of milliseconds (positive or negative) in the box labelled "Delay audio track by"
Save with a new filename

B) If the difference increases as the movie plays:

From under the "Video" dropdown menu, select "Framerate" - and select "Change so video and audio durations match"
Save with a new filename

Let us know of your success ;>}

[jeffareid]

I'm only working with the VOB file right now. The audio gets out of sync while just playing the VOB file from VirtualDub, but does not get out of sync if I play the VOB with PowerDVD.

The variance is not constant, and I already tried matching frame rate to audio and that didn't work either.

I suspect that the VirtualDub just can't handle the "discontinous timestamp" in the audio stream. I would assume that a working program would either fill a void with silence if the timestamp was ahead of the video, or it would skip ahead on the sound if the timestamp was behind the video.

I'm guessing that "discontinous timestamps" are silent sections between scenes, or maybe just there to make sure that sound and video stay in sync.

Regardless, I have yet to find a VOB to AVI conversion utility that isn't choking on this and getting the audio out of sync.

However, PowerDVD player works just fine, and I can use fraps to capture video and sound just fine. I would like to find out what the actual frame rate is so I can set fraps to capture at the exact same frame rate. One VOB utility shows the VOB file FPS at 29.97, the other at 23.976.

[jeffareid]

I'm trying DGDecode, and it may be working, will post later on.

I'm using Adobe Premiere Pro 1.51 to finalize the clip, so .m2v and .wav files from DGDecode will work just fine.

I tried renaming a VOB file to MPG, but Adobe choked on it, probably because of encoded frames from the DVD. Anyway to create a VOB with no encoded frames?

[jeffareid]

DGDecode worked. I was able to use Adobe Premiere Pro 1.51 to produce a short clip from near the end of a VOB without any video / audio sync issues.

[niann]

What are you trying to do with the VOB files? Prep them for import to Premiere or simply to convert the VOB files to an .avi format?

Cheers!