DVD-Lab Audio Sync Problems

[evader13]

I have been working all week on this and can't figure it out. I've read so many posts and guides and nothing I try works. I have a 2-hour mpeg movie that is in perfect sync throughout the movie, but when I import it into DVD-Lab and compile it to DVD, the sound is out of sync. What happens is the audio starts off fine then gradually loses sync by the end of the movie. It doesn't matter if DVD-Lab demuxes the mpeg or if I demux myself and import the seperate audio file - it still ends up out of sync (even after seven different attempts). What is going on?

[reboot]

I have a 2-hour mpeg movie that is in perfect sync throughout the movie

What works on your computer has (almost) nothing to do with what plays in a standalone.

Is the demuxed audio the same length as video?
Is the demuxed audio at the correct frequency?
What did you use to GET the audio, from what source?
Is this an encoded audio from tmpgenc or other VIDEO encoder?
Is the source audio 48khz?
Is the source audio mp3?
Is it VBR?

Now that I've given you something to think about, download SSRC (if you're using tmpgenc) and use it to do the audio.
If you're not using tmpgenc, extract audio, full processing, to .wav in virtualdub/mod, and use that .wav during encoding...
Better yet, transcode the .wav to ac3 in ffmpeggui, and use it during authoring only, after you've encoded the video only.

[evader13]

[quote="reboot"]

Is the demuxed audio the same length as video?

I'm not sure. I'll need to check. That could be the problem.

Is the demuxed audio at the correct frequency?

Um.. not sure. How do I determine this?

What did you use to GET the audio, from what source?

Several different tools (VirtualDub, Goldwave, Tmpgenc). From the mpeg and the original avi file.

Is this an encoded audio from tmpgenc or other VIDEO encoder?

Yes and yes. I've actually tried several different options.

Is the source audio 48khz?

Yes it is.

Is the source audio mp3?

No.

Is it VBR?

As far as I know. Still not 100% sure what this means actually.

Now that I've given you something to think about, download SSRC (if you're using tmpgenc) and use it to do the audio.
If you're not using tmpgenc, extract audio, full processing, to .wav in virtualdub/mod, and use that .wav during encoding...
Better yet, transcode the .wav to ac3 in ffmpeggui, and use it during authoring only, after you've encoded the video only.

I'll try the SSRC and ffmpegGUI and see what happens. I used the VirtualDub exactly as you said and that didn't work.

Thanks.

[reboot]

48khz is correct.
If it's not mp3, what is it?

I would extract (full processing) the .wav in virtualdub. Transcode to ac3 in ffmpeggui, and then use that ac3 during authoring.
When encoding the video, what is the original framerate? What framerate are you attempting to encode it to? If NTSC film, are you applying pulldown?
What encoder are you using?

[evader13]

Maybe it was mp3, I can't remember now. I've done so many things this past week, I'm starting to get confused. I stupidly deleted the original avi file after converting it to mpg with tmpgenc. I don't remember the original framerate of the avi, but the mpg is now 29.97. It has 2:3 pulldown applied. I may have to go back and acquire the avi again and start over.

The length of the video is: 2:13:41, audio is: 2:13:50
Is that enough to make a difference?

[reboot]

The audio usually ends up longer, but still sync's in DVDLab. I have NO idea why, and never bothered to find out.
There are multiple ways to fix audio sync. Just search for a few posts on the topic.
Here's a guide for svcd that works, just change the numbers to 48000 wherever you see 44100:
http://club.cdfreaks.com/showthread.php?s=&threadid=59487