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dirtfloorcracker
2008-04-05, 11:23 AM
OK so I'm trying to do a re-author of a concert DVD and add new audio. From my research here I know I need to demux to get back to seperate video & audio files, then use editing software to synch new audio.

Im using DVD decrypter. I used a guide from videohelp found here: http://forum.videohelp.com/topic224833.html#dvddecrypterdemultiplex

What I ended up with are two mpeg2 files and an ac3 audio file. I am using Vegas to edit the video. Problem is, Vegas only recognizes one of the mpeg2 files, and its only a short section of the video, it doesnt recognize the other mpeg2 file at all, and does not recognize the ac3 audio track. I tried to open the ac3 audio track in several audio editors (audition, wavelab) with not much luck. The only app that would open it (wavelab) gave me just static when I played it back. Oh and you could see by the waves something wasnt right.

Here is the stream info from decrypter:
0x80 - Audio - AC3 / 2ch / 48kHz / DRC / LBA: 1265 / PTS: 00:00:00.455 / Delay: 232ms
0xE0 - Video - MPEG-2 / 720x480 (NTSC) / 4:3 / LBA: 1201 / PTS: 00:00:00.222 / Delay: 0ms

Attached is a screenshot showing you what the files look like.

Any suggestions? Anyone ever run across problems like this when demuxing? Why can't I open the files in Vegas?

Any help is greatly appreciated!

pawel
2008-04-05, 05:25 PM
Download free AC3 import plugin for Audition http://www.vuplayer.com/audition.php or this http://ac3filter.net/projects/audition

You don't need to sync with Vegas, Audition is more precise, imo.

dirtfloorcracker
2008-04-05, 06:06 PM
OK... that helps, thanks! So after a little more research, I found that Vegas doesnt read mpeg2 files? But, I realized I dont need vegas anyway, since that would require re-rendering. So I just need to synch my new audio with the old (ac3) audio in Audition, export as wav and it should line up in architect for the re-author, being sure not to re-render when creating the dvd files...

Let me know if I'm on the right track...

stantheman1976
2008-04-05, 07:23 PM
You do not have to re-render you're whole project with Vegas. Use it to sync your new source and render just the new audio track that you've adjusted. Then when you author use the original MPEG-2 and import your new audio track. Vegas can read MPEG-2 files but you may need to MPEG-2 plug in.

Tubular
2008-04-06, 01:19 AM
here's one way to get large unsegmented .m2v & .ac3 (or .wav, etc.) files from your DVD consisting of the whole show:

rip with DVD Decrypter in file mode, rip the .VOB, .IFO, and .BUP files. do not demux with DVD Decrypter. you can also use windows drag and drop because you're not demuxing yet.

use VOBMerge to merge the large .VOB files (the show footage, not the menu files) into one large .VOB. get it here free:
http://download.videohelp.com/download/vobm250.zip

use ProjectX to Demux the large merged .VOB into .m2v and .ac3 or whatever your audio is. get it here free:
http://download.videohelp.com/download/ProjectX_090.4.00.zip

pawel
2008-04-06, 06:31 AM
Tubular, it's nonsense to follow all these steps as you may insert (in right order) all VOBs into ProjecX and demux them at once. The result will be a single m2v and audio file(s).

dirtfloorcracker
2008-04-06, 10:40 AM
Thanks guys, I'll give the proectX method a try. Here's what I've done so far, and I got really close, but Im still hung up.

First, as suggested, I grabbed an ac3 plug-in for audition. That worked great. Now I can work with the original audio...

Then I found a program called Smart Ripper, which gave me the best results yet for demuxing the video to mpeg2.

Here's a little wrinkle in this project. The show was actually authored kinda jacked up in that it was done on a stand-alone burner, and each song is broken into a different "movie" on the dvd. (instead of one big movie with multiple chapters.)

Now Smart Ripper gave me the option to do what I thought was a great thing by appending each movie's demuxed mpeg2 file to the previous one, creating one big mpeg2, and did the same thing with the ac3 files. HOWEVER, before I spent time re-synching the new audio to the old "merged" ac3 file, I wanted to make sure the original files were all still synched after this smart ripper "merge" of files. I dropped those two files into architect and at the end the synch was OFF by like 5 seconds. WTF???

So this brings me back to my original problem. It would be IDEAL if I could just bring the mpeg2 files into VEGAS, so I could re-synch the damn audio with this "merged" video file... That way when I re-render the NEW audio out of vegas, I know it would line up with the mpeg2 file. I tried to find an mpeg2 plugin for vegas (im running v.6) but no luck. All I could find was the main concept plugin for rendering mpeg2 OUT of vegas, not bringing one INTO...

Thanks guys, I hope all that makes sense. Let me know what you think.

Tubular
2008-04-06, 10:43 AM
Tubular, it's nonsense to follow all these steps as you may insert (in right order) all VOBs into ProjecX and demux them at once. The result will be a single m2v and audio file(s).

OK, thanks, I didn't know that.

pawel
2008-04-06, 11:34 AM
Standalone recorders very often output AC3 audio which has missing frames or is not exactly synched with video after demuxing. ProjectX is excellent application but it doesn't corrects AC3 errors.

I used TMPGEnc DVD Author 1.6 to overcome these issues - author or just mux again to DVD and then demux in ProjectX. Also VideoReDo is very good, if not better. Unfortunately both programs are not free.

dirtfloorcracker
2008-04-18, 12:52 PM
Just wanted to say KUDOS to Pawel, your info was the key that finally opened the lock. I got ahold of VideoRedo and that solved the issues. As you suggested, I opened the standalone authored DVD files in VideoRedo, muxed that to new DVD files, then demuxed those in ProjectX and the audio sync matched up with the video perfectly. I was even able to edit out a few unwanted glitchy clips from the start of the video, which VideoRedo does WITHOUT rerendering the m2v (which is a godsend).

Now, I still wasnt able to bring the m2v into vegas, but I didn't need to. I converted the ac3 audio to WAV using Audition (had to get an ac3 plugin to open the demuxed ac3), brought the converted WAV into Vegas, synched my new (pristine SBD) audio with the converted WAV, then rendered the SBD audio to a new WAV file. I was then able to bring the demuxed m2v and new audio into Architect, and it was perfectly synched! Now I just gotta create some menu pages and I've got an awesome re-author job complete!

Wow, what a learning process! This was baptism by fire. If I got through this, I feel confident I can handle any future re-author jobs.

One question though. Is the ac3 synch problem only existent when demuxing from a standalone authored DVD? I assume if I demux a dvd authored in vegas or tmpgenc or other app, that uses ac3, or LPCM for that matter, the synch should stay intact?

Again, THANKS for the guidance. As always this board is an amazing learning tool. I will be uploading the show soon, but I have a feeling some other folks have been working on this same project. We'll see who gets done first. I won't say here what it is, but Brownie points to anyone who can guess by the context clues in this thread:-)

pawel
2008-04-19, 09:19 AM
Just wanted to say KUDOS to Pawel, your info was the key that finally opened the lock.
Cool that I could help :wave:

I opened the standalone authored DVD files in VideoRedo, muxed that to new DVD files, then demuxed those in ProjectX
LOL: you can demux directly from VideoRedo, so no need to go again with ProjectX. However, both applications are great, it's better to avoid unnecessary multiple steps as there is bigger chance for an error.

VideoRedo: if there is only one audio stream, you may demux by selecting File > Save Video As... or File > Ad Edits To Batch Queue... , and run batch manager after then.

Unfortunately VideoRedo doesn't handle multi audio streams at once. If you have marked edit points, and you select other audio stream then all marks are gone. To overcome this shortage, you need to save project, and then edit manually Vprj project file - it's in text format - to change audio PID. Open changed project file, and run the process again. You will get second audio stream and again demuxed video.

One question though. Is the ac3 synch problem only existent when demuxing from a standalone authored DVD?
From some standalone recorders, not all. If I re-author a standalone DVD, I check these errors in ProjectX. It will save them in a log file stating discontinuity found in (frame number). They will appear in form of very short audio drop outs, jumps or so.

I assume if I demux a dvd authored in vegas or tmpgenc or other app, that uses ac3, or LPCM for that matter, the synch should stay intact?
Hopefully yes ;-) People report syncing issues with authoring programs. I didn't have any problem with these I use (Maestro, DLP, TDA, Vegas, AfterFX) but I believe that most problems are caused but erroneous source material rather than by rendering or muxing process.

AC3 is the only format used by DVD which should/has built-in time code, like video, so any demuxing program may use it for reference when syncing and determining potential audio delay. I don't remember if AC3 always has the time code but at least there is such option.

Cheers,
Pawel

dirtfloorcracker
2008-04-19, 02:47 PM
Thanks again Pawel for the follow up info!:clap:

LOL: you can demux directly from VideoRedo, so no need to go again with ProjectX. However, both applications are great, it's better to avoid unnecessary multiple steps as there is bigger chance for an error.

Thats cool, good to know. Just a FYI, I was going from your advice here:

author or just mux again to DVD and then demux in ProjectX. Also VideoReDo is very good, if not better. Unfortunately both programs are not free.

Which made me think I needed to use ProjectX AFTER muxing from VideoRedo.


Unfortunately VideoRedo doesn't handle multi audio streams at once. If you have marked edit points, and you select other audio stream then all marks are gone. To overcome this shortage, you need to save project, and then edit manually Vprj project file - it's in text format - to change audio PID. Open changed project file, and run the process again. You will get second audio stream and again demuxed video.

:hmm:Ok you lost me there, a bit over my head me thinks. Thank god I only had one audio stream.


From some standalone recorders, not all. If I re-author a standalone DVD, I check these errors in ProjectX. It will save them in a log file stating discontinuity found in (frame number). They will appear in form of very short audio drop outs, jumps or so.

OK, I assume you get this log AFTER doing the demux?


Thanks again for your help. You and Saltman get my MVP technobabble awards. Oh, and I should add AAR.oner to that list. You guys single handedly have taught me how to create DVDs. Oh, tubular too, in this thread. You're AC3 plugin advice was a key part of this as well. I wish this board had some type of reward points system ala taperssection.com, I would be giving out +'s all around.

NOW, next up in my dvd education, multicams. I don't have a project to experiment with yet, but should soon as I just aquired a second miniDV cam. I'm sure I'll be posting here for advice when I cross that bridge. So far I know I need to upgrade to Vegas 8, as they have made it much easier in that version. I've got it sittin on the HD, just need to install...

Keep an eye out folks, I've got some hellafied vids to seed soon. Oh, but it will probably be under my other user name, skotdee.

:wave:Later
SD

pawel
2008-04-19, 06:06 PM
Thats cool, good to know. Just a FYI, I was going from your advice here: [...] Which made me think I needed to use ProjectX AFTER muxing from VideoRedo.
There is something like a manual aka help file ;)

:hmm:Ok you lost me there, a bit over my head me thinks. Thank god I only had one audio stream.
It's not complicated - just insert the right number for the audio stream PID in the VideoRedo project file. The procedure:
1. Open a video / DVD
2. Make cut points
3. Save a project file
4. Demux video
5. Select second audio stream Tools > Select Stream - cut points are gone
6. Save the project file under new name
7. Open both *.Vprj project files in the Notepad and get numer of the audio stream PID from section <AudioStreamPID>xxx</AudioStreamPID>
8. Copy audio PID from the second to the first project file which has defined cut points.
9. Open changed *.Vprj and once again demux the video.

Annoying as hell but such this program works :lmao: The author promised to improve it in a future release.

If you want to demux only without any cut points then you don't need to follow the above steps. Just demux twice, selecting each time audio stream you want to get.

OK, I assume you get this log AFTER doing the demux?
Yes.

You and Saltman get my MVP technobabble awards.
Thanks :D