It turns out that what I really need to fix this sync problem is a way to turn a .VOB into an .avi without changing the duration of the video at all. I'll explain below, but I've tried a lot of methods for converting the video, and for an hour and a half of video, they all seem to end up about a second off from the original DVD duration (as far as I can tell).

I'm kind of a noob to all this, but I have spent some time trying to figure out how to fix this problem. I'm trying to replace the audio on a DVD with custom audio (like adding a soundtrack) with minimal reencoding of the video (I want to only reencode on DVD rip).

Here's the problem: The video duration changes when converting from VOB to a format that I can use for creating the soundtrack.

Using DVD Shrink 3.2 I rip some video to a big .VOB file. What I want to be able to do is demux the video (I've done this with VOBEDIT and REJIG), replace the audio with a custom track, and then use IFOEDIT to combine the original demuxed .m2v files. That works fine, but I need to use a program (I use Premiere) to line up the new audio with the video, and so this program needs a compatible video format, like Windows Media Video 9, or MPEG-1. I've figured out that this conversion is the source of my sync problems, because the duration of the video changes slightly when transcoded. I'll get back to that in a second, but here's the rest of the process:

Once I have my audio with soundtrack added, I save the audio to an avi with no video (it's fast and the only option I've found in Premeire for getting audio only), then I use AVI2WAV to strip the .wav file from the videoless .avi (other progs wouldn't open the .avi), then I convert the 44KHz .wav to a 48KHz .ac3 using the BeSweet AC3Machine. Using IFOEDIT, I combine this .ac3 with the .m2v file from VOBEDIT to create new VOBs that I can burn to DVD with Nero. That all works too.

Back to the video duration problem.... I've been working with a movie that is 1:41:48 and 16 frames long. When I convert this to WMV9 (I've mainly used VirtualDubMod or AVS Converter to do this step, since they both open VOBs), the video length changes to 1:41:47 and 14 frames, which is a little more than a second off, which is very noticable for the sync. If I export the audio only from the VOBs using VDubMod, the duration stays correct and is not shortened. If I encode to VCD, the total length changes to 1:41:48 and 8 frames, which is close to the original, and worked pretty well for this particular video (my custom soundtrack was barely out of sync by the end), but longer video creates a bigger problem.

So the big question is, is there a way to ensure that the duration of the video stays exactly the same when converting from .VOB to .avi?

My most recent attempt was to use the "Change so video and audio durations match" option in VirtualDubMod usder Video\Frame Rate. I also tried changing the frame rate from FILM (which is the DVD frame rate) to 29.97. At some point I messed around with the Inverse telecine settings, since this seems like it could definitely be a 3:2 pulldown removal problem, but nothing I tried helped.

Do any of you kind experts have any advice?


Thanks!
out_of_sync