Fixing / Determining Audio Sync Issues With Only Some DVDs

[TheNut]

Hey all,

I've been converting some of my DVD collection over to digital MP4 format and while some DVDs have converted over well, others not so. Thus far I've converted 2 DVDs with no problems + one with subtitles (cool that MP4 supports that). The past couple of days I've been trying to figure out why 2 other DVDs have audio sync issues. Both the audio and video are timed correctly (according to their metadata), but something somewhere is getting out of whack. With one DVD, DGIndex reports a 0ms audio delay, but there's clearly a sync issue as you play the video. It seemed to be a constant offset as you seek through the video. With the other DVD, DGIndex reports -16ms delay, but even with that correction entered (either in AVS or MeGUI), the video and audio are totally out of sync. As you seek, the audio gets more and more out of sync (audio faster than video, frame rate issue?). I'm following a typical process you could say, so I don't know or see why I should really horse around with timing and framing stuff unless that sort of thing is necessary, but I'd rather not commit that kind of manual labour.

I have my process outlined below.

1) Use DGIndex (version 1.5.6) to process the DVD vobs
- Using Forced Film and selectively demux the English surround stream.
- In the case with one DVD, I had to clip the part of the last VOB because it contained extras at the end of the credits (bizarre structuring). DGIndex seemed to demux the correct amount of audio though (metadata time matched with video).

2) I wrote an AVS script to mux the video and audio. AVS downmixes audio channels into stereo using a standard downmix calculation.

3) I use MeGUI to open the AVS script and convert audio to AAC, VBR 128bit. I compiled my own FAAC encoder (v1.28). Note that I also tried CBR for argument's sake, no luck.

4) I use MeGUI to open the AVS script and convert using 2-pass X264 with generally slow settings (first and second pass use the same settings, I'm picky). I compiled my own X264 executable (20091204-2245).


So other than that I'm not sure what else I can do. I skipped those DVDs for now, but I have a feeling more are going to crop up and unless I figure out what I'm doing wrong, I'm going to be stuck with a limited converted collection :\ IS DGIndex reliable?

[Baldrick]

Use another tool for just those dvds? Like staxrip, handbrake, xvid4psp and see how it works.

And how do you rip? What software?

[manono]

1) Use DGIndex (version 1.5.6) to process the DVD vobs

The chances are the synch is already ruined for any sort of reconversion by that point. Rather than decrypting the entire DVD, decrypt just the movie. And as Baldrick asks, what are you using to decrypt it in the first place? And is this a newish movie with one of the newer copy protections?

DGIndex reports -16ms delay, but even with that correction entered (either in AVS or MeGUI), the video and audio are totally out of sync.

That's got nothing to do with your problem. You can't even detect a -16ms asynch. Again, it's nothing to do with DGIndex. You could remux the audio and video right then (say, as an MPG), and it would be out of synch.

[TheNut]

Thanks for this tips guys. I'll give those apps a shot tonight and let you know how it works out.

I'm using the rather old DVD Decrypter to decrypt the DVD. It seems to work fine since running the DVDs in their ISO format don't have any problems. I recall only have one decrypt issue with POTC 3 a long time ago, but somehow it self-corrected itself. Not sure how that worked.

[manono]

Try getting just the movie and not the entire DVD, using the free DVDFab HD Decrypter perhaps followed by running the VOBs through FixVTS, before then beginning with DGIndex.

[TheNut]

I was in the middle of converting another DVD that had the same sync issue. I gave Handbrake a try (seems to be mentioned a lot) and the results came out perfect (much better actually with anamorphic settings saved). As manono brought up, I'm thinking manually picking VOBs instead of properly getting the main movie was the culprit here.

Needless to say, Handbrake is also quite more efficient at converting DVDs. Saves me quite a lot of hassle. Solve one issue and gain a totally more productive tool. Doubleplusgood