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desta
3rd December 2006, 06:45
I recently finished a rip and encode of Pirates of the Caribbean: The Curse of the Black Pearl. It's a disney dvd, so I ripped it with RipIt4Me in Movie-Only mode, and then processed with FixVTS. I then created the d2v and demuxed the AC3 with dgindex, and went on to encode it with MeGUI.

After successfully encoding to x264, I muxed the new encode along with the ripped AC3. All going well so far. So I then started to watch the encode, only to find the audio was pretty noticably out of sync. I fiddled with the A/V sync in AC3Filter and it seemed it was almost exactly 500ms off.

I remuxed it again, thinking it may just have been a glitch, but again the same thing. I checked back to see if I had overlooked some audio delay on the ripped AC3, but the file name indeed stated "DELAY 0ms".

At this point I was thinking it had to be something to do with the ripguard protection generally found on Disney dvd's, so I ripped the DVD again, but this time after processing with FixVTS, I immediately told it to process [with FixVTS] again - I only actually expected it to check through the vobs, and not actually process anything the 2nd time, but it did... it started processing again with the "Found VCID.." etc etc messages.

As soon as it had finished, I let FixVTS go again for a 3rd time... again it started processing, and was picking up on the same LBA pointers that it supposedly processed the 2nd time.

I eventually decided to do the whole encode again, from the newly 3-times-over processed vobs. So, new d2v, demuxed ac3 again, encode etc.

Having now finished this 2nd encode, I muxed again with the AC3, played back, and there again the audio was out of sync.

I'm now a bit clueless as to what's gone wrong. The strangest part is I actually did a rip/encode from the very same dvd earlier this year, with no sync problems whatsoever. The only reason I've revisited it, is because I was never too happy with the final quality of the video. That time however, I re-encoded the AC3 to AAC... otherwise I'd just rip the audio from that and use it for this one.

I should probably point out that I did give the dvd a clean before reripping it this time, but it didn't seem to make much difference. Obviously the quickest solution would be to just set a delay of 500ms when muxing the video and audio (which I did try, and it worked), but the fact that it's out of sync anyway when it shouldn't be has got me slightly concerned. The only fairly major difference is that when I did the rip months ago that was in sync, I didn't use RipIt4Me, and therefore didn't process with FixVTS or remove the unreferenced video that I found present this time.

blutach
3rd December 2006, 07:14
1st question - despite all your FixVTS processing, does the rip play OK on a software player? If so, the rip is fine and we can eliminate that - it becomes a muxing, audio delay issue.

As an aside, and people can correct me if I am wrong, but I think POTC1 was not protected by Ripguard.

Regards

desta
3rd December 2006, 07:42
Do you mean do the ripped vobs actually play back fine? If so, then yeah they play ok.

From checking the RipIt4Me logs, it does seem there were no protected cells, but as I said earlier, using RipIt4Me (and FixVTS) was the only difference in the ripping/encoding procedure this time, so I'd be more inclined to think that it's not down to incorrect muxing...

setarip_old
3rd December 2006, 07:47
@desta

Hi!That time however, I re-encoded the AC3 to AACAnd if you repeat this procedure with your current rip, is the AAC audiostream in synch with the video or not?

desta
3rd December 2006, 07:50
Hi setarip...

No, it's still out of sync if I encode to AAC.

At the moment, I'm actually just thinking of using DVDDecrypter directly, not removing unreferenced video and/or processing with FixVTS, and doing the encode again, to see if it makes any difference.


Edit: I just ripped the dvd again using only DVDDecrypter, and compared the vobs to those ripped via RipIt4Me. Turns out the rip done with RipIt4Me is 11 frames behind the one done without it.

While I was there I checked the encode from earlier this year (that was ripped with only DVDD) against the encode done recently (RI4M)... the recent one was also 11 frames behind.

11 frames @ 25 fps = 440ms worth of difference. Bit of a coincidence. Oddly though they all report the same total amount of frames.

setarip_old
3rd December 2006, 09:28
You might want to carefully review and experiment with the various "Remove" settings in the "Advanced Options" section of the "RipIt4me" "Preferences"...

desta
3rd December 2006, 20:22
Yeah, well I just finished the new encode, having only used DVDD at the start, and it all works fine. No sync problems.

You're most likely right.. it's probably one of the remove functions, but what puzzles me slightly is that when using RI4M for this particular encode, the end result is that the video lags behind - the audio has to be actually given a delay to put it back in sync.. so it's almost as if RI4M has taken 11 blank frames from the end and put them at the beginning.

Unfortunately I usually have all the remove options ticked before processing, and till now it doesn't seem to have been a problem. There was unreferenced video (or at least DVDShrink found some in the check part of the procedure), so I removed that... whether or not that was the cause I'm not sure, but I was under the impression that if it wasn't referenced, it wasn't needed.

blutach
3rd December 2006, 21:27
There should normally be no unreferenced video in a movie only rip.

Sometimes, you get very small unreferenced video in the other modes. This is because the studios purposely author the DVD to start part way into the cell (if you open the ripped DVD in VobBlanker (http://jsoto.posunplugged.com/vobblanker.htm), you may get warnings about this). This is usually on a tiny cell or even an unplayed title.

However, in movie only mode, all tiny cells and unplayed titles are stripped away and this warning should not appear.

Strange occurrence.

Regards

setarip_old
3rd December 2006, 21:34
@desta

Things seem to get more complicated with virtually every new release and, apparently in this case with an older release that pre-dates the ripping/compressing software being used ;>}

For what it's worth, with releases that are other-than SONY related (SONY, Columbia-Tristar, etc.), I always try ripping directly with DVD Decrypter v.3.5.4 (In "File" mode, selecting "All files", NOT just "movie files")

If the rip is done completely, without having to create any dummy sectors, I know I'm "home free" with a good rip.

If the rip is done and does create dummy sectors, I know it's a simplistic version of "RipGuard" copy protection - and I load the rip into VOBBlanker, set a new output directory/folder, select "Process all" and then press the "Process" radiobutton.

If, and only if, DVD Decrypter v.3.5.4 generates an error message and cannot complete the rip, do I then use the "RipIt4Me" package.

Occasionally, I also just use DVD95Copy, which has never created any out-of-synch situations for me...

desta
3rd December 2006, 21:56
Ok, thanks for the advice. I'll keep it in mind.

blutach, I've actually had a few movies that have had unreferenced material left over from a movie-only rip. Brotherhood of the Wolf was another just recently, as was Superman: The Movie. The unreferenced material was small, only a few mb's, and removing it didn't create a problem.

setarip, when you've successfully ripped in File mode, do you then go back and do the rip again in Ifo mode, or just use the required vobs from the file mode rip? Just out of curiosity.

setarip_old
3rd December 2006, 23:32
I just use the required vobs...