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beara
09-08-2005, 04:36 AM
I've just made a bit of a basic error in not checking sync before burning to DVD and have got one DVD with awful audio sync problems. I use tystudio to extract then tyeditor to multiplex and this has always worked fine. I can't use either on their own because they both crach on my PC if I use them in any other combo.

Anyway, I've made a DVD of two important TV programmes and the sync is out. It out about 3 seconds on the first chapter and about 10 seconds on the second. I've deleted the shows off the TiVo and also deleted the ty files from my PC. Both are unrecoverable. (How stupid am I!!) :(

IS there any way I can recover this DVD and reauthor it?

Regards

Jules

captain_video
09-08-2005, 08:15 AM
Unless the physical space on your Tivo has been recorded over with new programs then you should still be able to recover any deleted recordings using EditTitle or TivoWebPlus, among others. You might try using TyTools with the "Patch Audio Holes" option selected. I use it exclusively for extraction and muxing and haven't had an audio synch error in years. I also prefer VideoReDo for editing as it has more features than TyTools and has a much easier interface to use.

I have one other suggestion for you - don't delete any shows until after you've authored them and checked the final results. If you don't have room to store them on your Tivo then extract and archive the raw ty file to DVD-RW disc until you need it. I've still got several decommissioned S1 DTivos sitting around that have recordings on them because I haven't authored all of the shows to DVD yet. They're mostly compilations of TV series that may be missing a sequential episode to complete a particular DVD and I can't author the DVD until the missing show has been aired. I've still got a couple dozen Simpsons episodes sitting in limbo because I'm missing just two episodes to complete the entire series of over 350 episodes aired to date.

beara
09-08-2005, 11:12 AM
Ta - that's a good tip about the ty files - should have done that!! I've looked at the TiVo using Tivowebplus but the shows have gone from my deleted shows list which makes me suspect they've gone for good. I'm now wondering if I can create mpegs from the DVD and re-sync the sound once they are as mpegs....

BustedSony
09-08-2005, 01:15 PM
As long as you have a good DVD you're in good shape. Rip the DVD in IFO mode with DVDdecrypter, this will provide a vob for each title or film on the disc. These vobs will be the same at the mpegs used to author the DVD. For the next step I prefer DVDlab; demultiplex with DVDlab, put the video and audio on the movie timeline, adjust offset. This wll give a new .mpa with the corrected sync. Then remux the .mpv and .mpa with Mplex. Instead of using DVDlab to adjust the sync the offset can also be adjusted in Mplex while remuxing. Once you have the vobs from DVDdecypter you can also split them with VirtualDubMod but this will render the mpeg audio to .wav, requiring rerendering to mp2. There is also a splitter in TyTool. It's true that the tystream should have been handled by TyTool in the first place with "fill audio holes" enabled, but sometimes audio sync is bad during broadcast, particularly from TCM, also an error can creep in during editing that adds or subtracts a GOP without cutting the audio to match, thus giving up to 15 frames, or half a second sync error.

captain_video
09-08-2005, 03:05 PM
Wow, that's a long and totally unnecessary process, IMHO. Try just copying the VOB files directly from the DVD. There's no need to rip the files (no CSS encryption involved) although DVD Decryptor may actually copy the files a bit faster than a straight file copy but it will copy everything in addition to the VOB files. You should be able to remux the files with TyTool but select the "fill audio holes" option as described previously. The result will be another mpg file that you can author with DVD-Lab or other tool or create VOBs with TyTool and author it there. If that doesn't work you could use MPEG2VCR and fix the GOP headers or use VideoReDo and perform a Quickstream fix. Either method should correct the audio offset.

BustedSony
09-09-2005, 04:38 AM
Try just copying the VOB files directly from the DVD.

Yes but that just copies the vob set, split into one gig sections that in no way represent the actual movie mpegs. MAYBE if it's a TyTool DVDauthor project then each odd-sized vob may be one movie, but they will still be cut after one gigabyte, thus splitting up the movie. How does one apply adjustment to one movie but not another if one ends and the next begins in the same vob? DVDdecrypter takes each movie to its own vob, even if it's 2 gigs or more in size. And ripping with DVDdecrypter is easy, very easy. The rest of the process for adjusting sync is the only way to do it. I have had to do this many times after finding sync was not to my satisfaction on just one out of three or four films on a Dtivo-DVD project. To correct the sync on one title in a finished DVD you HAVE to recover each title first! - in effect to decompile the DVD.

BustedSony
09-09-2005, 04:50 AM
I forgot to address this, sorry :o


You should be able to remux the files with TyTool but select the "fill audio holes" option as described previously. The result will be another mpg file that you can author with DVD-Lab or other tool or create VOBs with TyTool and author it there.

If the vob has been extracted from the tystream then it is too late to fill in the holes since the audio uses the video stream as its clock. ask JDliner. The audio will advance against the video at the hole or the video will glitch.


If that doesn't work you could use MPEG2VCR and fix the GOP headers or use VideoReDo and perform a Quickstream fix. Either method should correct the audio offset.

Yes these work well, and sync offset can be adjusted etc. BUT the problem can't be the result of audio holes in the first place, AND you do still have to work on each movie, not the whole DVD, which apparently has different problems with different movies in this case. I suspect the audio offset is nothing to do with extraction but is just something that happened during authoring. If the sync offset CHANGES during the title, then there is no easy fix. I've solved this by taking the audio to .wav, then adding black audio to counter the sync shift while looking at the video using the plugin in Sound Forge. Again not easy, but I'm open to suggestions... ;)

captain_video
09-09-2005, 08:23 AM
There are many ways to rejoin VOBs into one large file. IFOEdit (VOB Extras) and VideoReDo (joiner option) are just two that come to mind. I think there's even a way you can do it with TyTools. Doing a simple copy using a command prompt will also join the files (I forget the exact syntax but it's been posted here many times). Unless there's an option in DVD Decryptor I'm not aware of, which is always possible, you still get 1GB VOBs when ripping DVDs. IIRC, IFO mode just creates an ISO image of the entire DVD and doesn't join the individual movies into a single large VOB file. You can then use Daemon Tools to mount the image and access the files as you would a normal DVD. I think I've only used that method of extraction one time and found that I prefered my extractions in file mode so I never explored all the options with it.

I can't argue with your other points about your methodology because I've always extracted and muxed with the fill audio holes option selected. I haven't followed the TyTools thread in ages because it's always the same 2 or 3 individuals posting there all the time (with topics that are of little or no interest to me), except for the newbies asking the same redundant questions. I used to screw around with trying to repair out-of-sync ty files in my early days of extraction until I finally realized that most of the time it was leading to a dead end, at least with the tools we had available at the time. The best method is simply to set things up correctly the first time and you'll never have to deal with this kind of problem. I know it's nothing more than hindsight but consider it a lesson learned. There's no video that you absolutely can't live without nor is it likely that any particular program will never be rebroadcast. I always found that if the original recording was out of sync then the best thing to do was just record it again.

Now that I've got HDTV I rarely archive anything from my DTivos anymore, with a few exceptions. In fact, all of the series' I originally archived from DTV have been replaced with copies of DVDs that I rented from NetFlix. The audio and video are much better quality and easier to watch on my 60" HDTV than the original TyDVDs I created.

BustedSony
09-09-2005, 12:47 PM
Doing a simple copy using a command prompt will also join the files (I forget the exact syntax but it's been posted here many times).

No joining is needed.


Unless there's an option in DVD Decryptor I'm not aware of, which is always possible, you still get 1GB VOBs when ripping DVDs. IIRC, IFO mode just creates an ISO image of the entire DVD and doesn't join the individual movies into a single large VOB file.

Nope, sorry. when you select IFO mode the "input" tab shows each movie as VTS-01, VTS-02 etc. Select the "+" sign below each VTS and it will show that particular movie and its chapters. You can check running time to identify the movie. In options under IFO mode you set the movies to be complete on one Vob. ("Automatic" I believe) If one movie is 3 gigs you will get a 3 gig Vob, if another movie in the DVD is 1.2 gigs you will get a 1.2 gig vob, etc. -no joining is needed and no need to cut the DVD's vobs to separate out the movie that's wanted. DVDdecypter's Vobs in this mode are exact copies of the original mpegs used to to create the tracks when the DVD was authored. The OP can do his manipulation on just the movie with the problems then those VTS vobs can be renamed back to the original Mpeg filenames, and reused in the original project (if the project file was saved) to recompile the DVD - with the corrections.. (I always save the DVDlab .dal files for this purpose) I do this procedure so often that it's become second nature, I may have left out a step or two that I consider obvious. :o

You can use DVDdecypter in IFO mode for the movies, plus IFOedit for the Menus and graphics, to completely and accurately decompile all the assets of a homebrew or commercial DVD. Take a commercial DVD and just change the menu background or add your logo or edit the chaps, etc... DVDdecrypter is SO much more than just a CSS ripper!

BustedSony
09-09-2005, 12:54 PM
The best method is simply to set things up correctly the first time and you'll never have to deal with this kind of problem. I know it's nothing more than hindsight but consider it a lesson learned. There's no video that you absolutely can't live without nor is it likely that any particular program will never be rebroadcast. I always found that if the original recording was out of sync then the best thing to do was just record it again.

Hehe, I wish! My passion is Precode films on TCM and occasionally Fox, and those things DON'T get repeated very often. And they tend to air at lower bitrates which seems to more likely contribute to poor sync. So each DVD I make has the sync adjusted right to begin with. And if down the road I'm not happy with it I use the method described above to adjust it. HDTV is nice, but "Zoo in Budapest" is not, and never will be, broadcast in HD. :D

beara
09-10-2005, 04:23 PM
Thanks both, I've spent the day trying this with dvdlab and ended up with a wav file to re-encode. I've now swithced to videoredo which has given me a working mpeg in one pass for the first chapter, but is going to take several passes for the second as it's so far out. I like videoredo, it seems to cope with those issues very easily.

Thanks again :)

Regards

Jules

BustedSony
09-10-2005, 04:48 PM
Thanks both, I've spent the day trying this with dvdlab and ended up with a wav file to re-encode. I've now swithced to videoredo which has given me a working mpeg in one pass for the first chapter, but is going to take several passes for the second as it's so far out. I like videoredo, it seems to cope with those issues very easily.

Erm, if you have DVDlab you don't need anything else (except DVDdecypter.) The audio remains as MP2, nothing is rerendered at all from start to finish. Once you have the mpeg from DVDdecypter (the vts_oX.vob) drag it into the Assets window in DVDlab. It will ask you if you want to separate the video and audio, say "yes." Once the video and audio are in assets then drag them to the movie timeline. select then Right-Click on the audio track and select "Audio Delay" Enter the value you want, 41ms equals one film frame, 33ms one video frame. To correct audio lagging video you use a negative value. This creates a "delay.mpa" in the working directory. Remux the video and audio using mplex and that's it, you have an mpeg with corrected audio sync. 5 minutes work total. Here's a sample command line for Mplex

mplex -f9 -o copyout.vob "The Sea Bat-RAQUEL_TORRES-MGM-1930_0.mpv" "The Sea Bat-RAQUEL_TORRES-MGM-1930_1_delay.mpa"

If you use video redo then you're rerendering the whole mpeg and it takes hours.

captain_video
09-10-2005, 10:03 PM
If you use video redo then you're rerendering the whole mpeg and it takes hours.
Actually, VideReDo takes very little time to remux mpeg files. I can usually do a 1GB file in well under 10 minutes.

BustedSony
09-11-2005, 10:21 AM
Actually, VideReDo takes very little time to remux mpeg files.

Ah ok. The main point is that to simply adjust audio offset one doesn't have to go outside of DVDlab, which will even demux the file. And it wasn't necessary to make a .wav (through VirtualDubMod I assume) if one has the demuxing tool available on DVDlab. Also GOP timecode can be repaired in DVDlab. What I HAVE used ReDo or Womble for is to "fix" GOP headers if needed to make 480 X 480 DVB fully compliant with DVD specs. But that adds to the file size and is not needed when using TyTool DVDauthor or the regular DVDlab.

captain_video
09-11-2005, 04:44 PM
Just out of curiousity, which version of DVD Lab are you using?

BustedSony
09-12-2005, 12:48 AM
Just out of curiousity, which version of DVD Lab are you using?

If I remember, (they're not at hand,) 1.33 at home and 1.51x Pro at work. The latter is fussy about GOP length and often doesn't like Dtivo vobs unless they've been adjusted in Redo or womble, the regular DVDlab will work with practically anything that's Mpeg2 as long as the "alternative' engine is used, with "Force Audio on all tracks." DVdlab Pro beta also didn't mind Dtivo vobs but would sometimes make a DVD that would freeeze or show block artifacts.