Demuxed audio from PGCDemux out of sync with video

[ArtOfLosingMFZB]

Hey all, I'm hoping someone will be able to help me with this in words I can understand.

So I have a DVD and I'm altering the audio. The plan was to demux the audio, alter it, and then remux it back into the DVD using MuxMan and VOBBlanker.

Here is what is happening:

Demux using PGCDemux
Mode: by PGC --> there is only one file to choose from and it's 02:41:16 in length. However, the resultant AC3 file is 02:41:24. If I mux the whole thing back together using MuxMan, without altering anything in any way, the audio is now out of sync, whereas the original DVD plays fine.
I checked for any audio delay in PGCDemux and it reports none.
The DVD has only one angle (no alternate angles or anything like that would mess with it.)
The audio actually starts out in sync, and then gradually slips more and more out of sync.
Another piece of info that could be useful is that it is an episodic DVD, and it seems that the first episode plays fine, in sync. But each subsequent episode slips further and further out of sync.

Please, I'm hoping somebody can help me out as this is becoming an increasingly frustrating process. I've searched elsewhere on the net for those with a similar problem, but I have yet to find a clear solution. It would appear as if others may have had similar problems, with the same production studio's DVDs, actually (Funimation), but I can't make heads or tails of what they are saying. So if someone could please explain to me why this is happening, I would be forever grateful.

[DarrellS]

I would re-rip the episode DVD as separate vobs. Each episode should be it's own chapter.

You can download a 30 day full function trial of DVDFAB if you don't already own it. Under DVD to Mobile, select your DVD and select your ouput folder. Click next and then click Conversion Settings. Under Device at top, choose Vob in drop down window. Under Encoding Method, choose Pass Through (should be default). Under Split, choose Split By Chapter and then click OK to close the options window. Click Start. This will let you work on each episode on it's own.

Not sure what you mean about altering the audio and putting it back in the DVD.

[manono]

The audio actually starts out in sync, and then gradually slips more and more out of sync.

I doubt that's true. Your statement that the first episode is in synch all the way through backs me up. You're getting little 'jumps' at the end of each episode with the delays piling up with each new episode.

You might tick 'By VOB ID' in PGCDemux, rather than using the default 'By PGC'. First confirm that each VOB ID is the length of each episode. If the episodes are divided by VOB IDs, demux by VOB ID and encode them all separately.

I doubt each episode is a chapter as DarrellS seems to think. They might not be VOB IDs either, but you won't know until you check.

[ArtOfLosingMFZB]

You're getting little 'jumps' at the end of each episode with the delays piling up with each new episode.

Yes, that is exactly what is happening. The audio gets more and more out of sync with each new episode.

You might tick 'By VOB ID' in PGCDemux, rather than using the default 'By PGC'. First confirm that each VOB ID is the length of each episode. If the episodes are divided by VOB IDs, demux by VOB ID and encode them all separately.

I doubt each episode is a chapter as DarrellS seems to think. They might not be VOB IDs either, but you won't know until you check.

Yes, the episodes are divided by VOB ID and I would do it that way, but the problem with that is that I would no longer be able to swap the altered audio back in to the original DVD using my Muxman/Vobblanker method. Or would I? Is there something I don't know? When I pull the DVD up in Vobblanker, it only gives me the option to swap the full PGC, there is no option for me to simply swap by VOB ID.

*Orrrr what would happen if I demuxed each episode by VOB ID, then merged all of the fixed audio together in sequential order, and then muxed that back into the original DVD. Might that be the solution?

[manono]

Yes, the episodes are divided by VOB ID and I would do it that way, but the problem with that is that I would no longer be able to swap the altered audio back in to the original DVD using my Muxman/Vobblanker method.

You're correct, and I consider that a shortcoming of VobBlanker that you can't replace by VOB ID as you can by PGC or by cell.

I think the way I'd tackle it is by first making the audio the same length as the video for each episode/VOB ID. Account for the delay in every VOB ID after the first one, and also remove the end audio that extends beyond the video (you said the total audio is longer than the length of all the episodes combined). DelayCut can do that. That longer-audio-than-video problem should even take care of itself when making the D2V project file using DGIndex.

Alternatively, remove the delay as given by PGCDemux for each episode after the first, and pad the video with black frames so that it matches the length of the original audio. You're using AviSynth scripts, aren't you?

Then encode all the videos (either separately or joined together) and join the videos and all the audios by using the 'Add' button when muxing with Muxman.

Or keep the episodes separate and redo the menus in something like DVDAuthorGUI (perhaps even using the same menu backgrounds from the original DVD) so that each episode becomes a separate title/PGC within the same VTS. That way, except for removing the opening delay, nothing else has to be done with the audio.

[ArtOfLosingMFZB]

I think the way I'd tackle it is by first making the audio the same length as the video for each episode/VOB ID. Account for the delay in every VOB ID after the first one, and also remove the end audio that extends beyond the video (you said the total audio is longer than the length of all the episodes combined). DelayCut can do that. That longer-audio-than-video problem should even take care of itself when making the D2V project file using DGIndex.

Then encode all the videos (either separately or joined together) and join the videos and all the audios by using the 'Add' button when muxing with Muxman.

Thanks for the suggestions, I'm going to go ahead and give this one a try. And if it doesn't work, I'll try some of the other methods you've mentioned. Either way, I'll let you know what happens. I'm not using AVISynth scripts, actually, as I'm not very familiar with them.

[ArtOfLosingMFZB]

This DVD is immensely frustrating. I would really like to find out what the problem is. I really don't understand why this is happening.

I've been trying to remedy this problem to no avail. I just can't make any sense of it.

I think the way I'd tackle it is by first making the audio the same length as the video for each episode/VOB ID. Account for the delay in every VOB ID after the first one, and also remove the end audio that extends beyond the video (you said the total audio is longer than the length of all the episodes combined). DelayCut can do that. That longer-audio-than-video problem should even take care of itself when making the D2V project file using DGIndex.

Alternatively, remove the delay as given by PGCDemux for each episode after the first, and pad the video with black frames so that it matches the length of the original audio. You're using AviSynth scripts, aren't you?

Then encode all the videos (either separately or joined together) and join the videos and all the audios by using the 'Add' button when muxing with Muxman.

Here's the thing: up until I mux the files back together with MuxMan, there is no delay. Anywhere. The original DVD plays fine and PGCDemux doesn't report any delays. I've tried everything. I've:

-Demuxed by episode/VOB ID and everything is in sync.
--After that, I join all of the correctly synced video and audio by using the 'Add' button in MuxMan. Then I get the same sync problem.
--I also tried joining all of the synced audio from the VOB IDs together and comparing it to the AC3 file I get when I demux the entire PGC and they're the exact same.

-Then I had PGCDemux create a PGCVOB which I figured would give me correctly synced video and audio which, of course, it did. My plan was to sync up my altered audio to the correctly synced PGCVOB. Problem was, when I tried to sync the two audio tracks up, I discovered, again, that they were exactly the same.

-I also thought it might be a PGCDemux problem, so I tried using DGIndex for my demuxing process instead. But that just gave me the exact same files with the exact same re-muxing problems.

-Then I thought it might be a MuxMan problem so I used a different program to re-multiplex the VOB but I got the same problem.

*I don't think that DelayCut will help me, given that there is no delay to be found anywhere, up until I re-multiplex the VOB back together.

*Something weird to note: I'm doing this with two different language tracks, that is, I'm altering both of them. However, the two language tracks that I get also don't sync up to each other entirely. The first couple episodes are fine but then they are off by about 1 to 1.5 seconds for the rest of the time. I don't know if that is yet another problem that is occurring after I de-mux, but they both seem fine in the original DVD.

*Another odd thing is that, even though the resulting AC3 file seems to be longer than the video length (as reported by PGCDemux), when I re-mux the VOB back together, the audio is actually ahead of the video.

So what the hell is going on here?! Where is this problem occurring and how do I stop it?? I don't want to re-encode the video, and I'd prefer to avoid keeping the VOB IDs separate and re-authoring because, not only is that an arduous task, but then the Play All feature wouldn't really work correctly. And anyway, this should be a simple thing to do, I shouldn't have to do anything else. This should be working!! Why isn't it??!

I've read elsewhere about unreferenced cells. Could that have something to do with what is happening? I tried using FixVTS but that crap didn't work either.

So the problem seems to be occurring when I re-mux the VOB back together. Or maybe it's happening when I demux in the first place, but that wouldn't make sense because I tested all of the individual VOB IDs which were correctly synced and I still got the same problem.
Or could it have something to do with the way I rip the DVD? I used DVDFab Decrypter, if that helps at all.

[manono]

*I don't think that DelayCut will help me, given that there is no delay to be found anywhere, up until I re-multiplex the VOB back together.

I do, if what you said about the audio being longer than the video is true. You say there's no opening delay for any of the episodes, correct? But if the audio is longer than the video then it extends beyond the end of at least some of the episodes. So my earlier suggestion was to find out how long the audio is as compared to the video, and remove that extra bit. Delaycut can chop off the end.

There's also a chance not all the copyright protections were removed if this has advanced copy protection needing something more robust than DVDDecrypter to decrypt it to the hard drive. Sometimes FixVTS can be used on such DVDs to remove any unreferenced cells.

But, if this thing is so frustrating, and you have several reencoded episodes in synch, I think I might be tempted just to create a new DVD with these episodes as separate titles/PGCs, rather than the way it was originally with multiple episodes all in the same PGC.

[ArtOfLosingMFZB]

*I don't think that DelayCut will help me, given that there is no delay to be found anywhere, up until I re-multiplex the VOB back together.

I do, if what you said about the audio being longer than the video is true. You say there's no opening delay for any of the episodes, correct? But if the audio is longer than the video then it extends beyond the end of at least some of the episodes. So my earlier suggestion was to find out how long the audio is as compared to the video, and remove that extra bit. Delaycut can chop off the end.

Yes, the audio file is longer than the video for some reason and there is no opening delay for any of the episodes. However, as I said earlier, the audio actually seems to be ahead of the video. If what you are saying were true, than wouldn't it be the other way around?

There's also a chance not all the copyright protections were removed if this has advanced copy protection needing something more robust than DVDDecrypter to decrypt it to the hard drive. Sometimes FixVTS can be used on such DVDs to remove any unreferenced cells.

I used DVDFab Decrypter, not DVDDecrypter. I also tried FixVTS already and it didn't help.

[manono]

When you have a look at the cells in VobBlanker or PGCEdit or even PGCDemux, you don't see any tiny cells listed?

[ArtOfLosingMFZB]

When you have a look at the cells in VobBlanker or PGCEdit or even PGCDemux, you don't see any tiny cells listed?

Nope. The only tiny cell I see is at the very end of the PGC, but those tiny cells at the end seem to be pretty standard based on previous experience.

The problems I am having with this PGC make no sense.

[manono]

Yes, a short last cell is common. But I suspect there's something very unusual about this one. Because it's there that the audio becomes longer than the video. Do you agree? Because the VOB is in synch all the way through, but when the VOBs are joined for reencoding all of a sudden the audio is longer than is the video and the subsequent episodes are out of synch..

That last cell can be a single frame but it will be instructed to play for however long the audio is. When demuxed for encoding as part of the episode all you get is the single frame. You might try demuxing that last cell and comparing the video length with the audio length (even if the audio is silent). The video might be a single frame or two, but the audio might be maybe a second or so.

Or, failing that, just make a new DVD with the episodes becoming separate titles/PGCs this time, as I suggested earlier. Any authoring program can do it. Or get rid of that last cell from each episode before working on the DVD. VobBlanker can blank it. PGCEdit can completely remove it (but that may require redoing the chapter commands).

[ArtOfLosingMFZB]

Holy crap, I fixed it.

It was something that I probably should have tried much earlier, but I didn't think it was necessary, nor did I think that I should have to do it because I didn't understand why the problem was occurring in the first place (still don't, actually.)

Basically, I calculated the delay after the first episode using MediaPlayerClassic, and then adjusted the entire PGC's audio in Audacity to reflect that. Sure enough, it worked like a charm and now everything is in sync and I'm able to swap with VobBlanker, like I originally intended.

(Turns out, by the way, that the audio didn't actually get more and more out of sync after every episode, but rather it went out-of-sync after the first episode and stayed that way for the remainder of the PGC. Heh..., I guess I should have made sure of just what was happening with the sync before opening my mouth. Sorry about that. )

Thanks for all of your help, manono, I really appreciate you trying to figure out this problem with me.

Furthermore, your handy menu replacement guide helped me out when it came to replacing the music for the menus, so thank you for that as well!

I just have one more question for ya.

I'm following the guide on replacing the menu, but for some reason, my buttons keep coming out looking wrong.

Basically, instead of looking like this:


they end up looking like this:


Any idea why that's happening? I tried hitting yes and no when it asked me if I wanted to create buttons for both 4:3 and 16:9, but both times I got the same problem.

[manono]

Basically, I calculated the delay after the first episode using MediaPlayerClassic, and then adjusted the entire PGC's audio in Audacity to reflect that. Sure enough, it worked like a charm and now everything is in sync and I'm able to swap with VobBlanker, like I originally intended.

(Turns out, by the way, that the audio didn't actually get more and more out of sync after every episode, but rather it went out-of-sync after the first episode and stayed that way for the remainder of the PGC.

Audacity? So you reencoded the audio? For future reference, split the audio at the place where it goes out of synch all of a sudden. For this I use HeadAC3he. You'll have to do the splitting twice. Then, when all done, you'll have (for example) Part1.ac3 and Part2.ac3. Open one of them (probably Part2.ac3) in DelayCut and remove the delay. Rejoin during muxing using the 'Add' button in Muxman when adding in the audio. No reencoding of the audio. Unless you want to. Then, yes, it's easy to both add and remove audio in Audacity. Had you mentioned earlier that the audio went out of synch all of a sudden and only at a single place, I'd have suggested this because I've had the same problem in the past and used that method.

As for the menu problem, what changes or additions have you made? It looks to me like you added something new that also needs a new button and subpic made. That is, you also need to modify the underlying subpic, something the guide doesn't address because it was written for stuff that doesn't need new buttons. Some of the later comments do address it.

You can open the menu in DVDSubEdit and extract the subpic to have a look.

[ArtOfLosingMFZB]

Audacity[/URL]? So you reencoded the audio? For future reference, split the audio at the place where it goes out of synch all of a sudden. For this I use HeadAC3he. You'll have to do the splitting twice. Then, when all done, you'll have (for example) Part1.ac3 and Part2.ac3. Open one of them (probably Part2.ac3) in DelayCut and remove the delay. Rejoin during muxing using the 'Add' button in Muxman when adding in the audio. No reencoding of the audio. Unless you want to. Then, yes, it's easy to both add and remove audio in Audacity. Had you mentioned earlier that the audio went out of synch all of a sudden and only at a single place, I'd have suggested this because I've had the same problem in the past and used that method.

I actually had to re-encode the audio, regardless, so it wasn't a big deal. But I'll keep that method in mind for future reference.

And, again, my apologies for not realizing that it only went out of sync at a single place, I should have caught that.

As for the menu problem, what changes or additions have you made? It looks to me like you added something new that also needs a new button and subpic made. That is, you also need to modify the underlying subpic, something the guide doesn't address because it was written for stuff that doesn't need new buttons. Some of the later comments do address it.

Actually, the only thing I changed was the audio that plays during the menus, nothing else.

However, when I muxed the menu back together using MuxMan, I included the .sup files (two of them) that were extracted with PGCDemux. Could that be the problem? Perhaps I don't have to include the .sup files when re-muxing because that is something that PGCEdit takes care of when re-importing the menu, and that's why it's screwing up?

[manono]

You only changed the audio and got that result? Then perhaps you added in the SUP files incorrectly.. The first one (Subpictures_20.sup) is for Wide and the second (Subpictures_21.sup) for LB. That assumes that was how it was done originally, but it almost always is.

[ArtOfLosingMFZB]

You only changed the audio and got that result? Then perhaps you added in the SUP files incorrectly.. The first one (Subpictures_20.sup) is for Wide and the second (Subpictures_21.sup) for LB. That assumes that was how it was done originally, but it almost always is.

That... is exactly what happened. Actually, when I was first muxing the menus back together with MuxMan, I didn't know what to do with the SUP files as I didn't know what they were, so I panicked and didn't click anything for PS, LB, or Wide. Heh...

Of course, now that I go back and read your post, I guess I had misread it earlier, as I labeled the first one (Subpictures_20.sup) PS and LB and the second (Subpictures_21.sup) Wide, as opposed to the other way around. They seem to be showing up fine in VLC, though, so I wonder if I just got lucky? Though VLC is probably not a good indicator, so I'll have to try it on a 4:3 TV to know for sure, I guess.

[manono]

Wide and LB are the most common. Wide and PS is sometimes used. If it was Wide and LB and PS, then there would be a third SUP file. You can check if yours is supposed to be Wide and LB or Wide and P&S in PGCEdit. Open the original DVD. Right-click on the menu in question and hit 'Domain Streams Attributes' and it'll tell you in the new 'Streams attributes' screen that opens up..

[ArtOfLosingMFZB]

Hmm... in the 'Streams Attributes' window on the original DVD, the box marked 'Automatic Pan&Scan' is ticked. Also, when I right click on 'Menu Buttons', 'Group 1' shows the 16:9 menu, while 'Group 2' shows the Pan&Scan menu; 'Group 3' is grayed out. Does that mean that my SUP files should be marked Wide and PS?

If that's the case, then I have them flip-flopped while also labeling the first as LB in addition to PS. It still plays fine in VLC, but that may just be VLC's tendency to play anything you throw at it.

[manono]

Does that mean that my SUP files should be marked Wide and PS?

Yes, that's exactly what it means. I should have explained how to check first, but based on my experience Wide and LB is far and away the more common. Sorry for wasting your time there.

It still plays fine in VLC, but that may just be VLC's tendency to play anything you throw at it.

Or it could be that you have the Wide one correct and it's playing it as 16:9. When all done, you should test on both widescreen and old 'square' TV sets.

[ArtOfLosingMFZB]

Yes, that's exactly what it means. I should have explained how to check first, but based on my experience Wide and LB is far and away the more common. Sorry for wasting your time there.

Don't worry about it, no time was wasted: learning happened.

Or it could be that you have the Wide one correct and it's playing it as 16:9. When all done, you should test on both widescreen and old 'square' TV sets.

I tried it on an old 'square' 4:3 set and the menu still functioned correctly. I wasn't able to test out the 'Letterbox' function, though, as my Xbox 360 didn't let me view the menus that way. So... I guess I'm good?

[manono]

I tried it on an old 'square' 4:3 set and the menu still functioned correctly. I wasn't able to test out the 'Letterbox' function, though, as my Xbox 360 didn't let me view the menus that way. So... I guess I'm good?

Assuming you have the XBox360 hooked up to the 4:3 TV correctly and it plays DVDs in the correct aspect ratio, the Pan And Scan (which is how you finally did it, right?) should kick in automatically and show you the menu cropped from the left and right sides as compared to the menu you'd see on a 16:9 TV set where you'd see it widescreen. Same menu, widescreen on a widescreen TV and cropped on an old 'fullscreen' TV set. If it's Wide and P&S, you shouldn't ever see any letterboxing (black bars above and below) on the 4:3 TV set.

So, yes, I guess it's working the way it's supposed to. Good going!