Video/Audio Sync Problems Using VDubMod

[DFF]

Here are a couple of examples of issues I've been experiencing regarding the audio/video being out of sync in VDubMod when opening VOB's I'd ripped with DVD Decrypter.

(Found in VDubMod underneath Streams --> Report)

Ed Wood Chapter 8

---== Video stream ==---

Source :
Description: MPEG video stream
Length : 00:07:23.151

---== Other stream ==---

Source : [Input MPEG file]
Description : MPEG audio stream (AC3)
Length : 00:07:23.264

Sid And Nancy Chapter 20

---== Video stream ==---

Source : [Input MPEG file]
Description: MPEG video stream
Length : 00:03:16:405

---== Other stream ==---

Source : [Input MPEG file]
Description : MPEG audio stream (AC3)
Length : 00:03:14:880

As you can see, the audio from Ed Wood is [I]slightly longer than the video, whereas with Sid and Nancy, it's wildly off.

Any suggestions on how to sync them precisely?

Oh, and a couple of other things.

1)In VDubMod, when I open a VOB and press Input Playback, I can hear audio along with the video. It's just a tad out of sync with most files (like Ed Wood).

2)Someone suggested I convert to a WAV file when I open the converted AVI in VirtualDub; but in order to retain maximum audio quality, I don't wish to compress my audio. Just the video.

Thanks.

- J

EDIT: I just checked and rechecked this report from the next chapter Of Sid And Nancy and oddly enough, the sync is almost perfect.

---== Video stream ==---

Source : [Input MPEG file]
Description: MPEG video stream
Length : 00:03:39:094

---== Other stream ==---

Source : [Input MPEG file]
Description : MPEG audio stream (AC3)
Length : 00:03:39.072

What the hell???

[tebasuna51]

VDubMod don't report the Delay.

You can use DGIndex to extract the audio from the VOB and you can see the Delay needed.

[DFF]

Thanks.:)

In terms of converting VOB's to AVI's, I'm a novice, so it would very helpful if you, or someone else, could explain to me how to perform this process step-by-step.

[neuron2]

You can't use the delay value from DGIndex in VirtualDubMod if you open the VOB in VirtualDubMod. It will be correct only if you serve the video through DGDecode.

@DFF

Get DGMPGDec and read the quick start guide. When you've demuxed the audio you'll get the delay value in the audio filename. Then you can use that in your script via DelayAudio() or in VirtualDub's audio skew correction edit box. Get started with the guide I mentioned and then post again if you need to.

http://neuron2.net/dgmpgdec/dgmpgdec.html
http://neuron2.net/dgmpgdec/QuickStart.html

[DFF]

Thanks a lot man. You've saved me a LOT of time. I appreciate the help. :)

[neuron2]

We aim to please. :)

And welcome to the forum!

[DFF]

K, I've encountered a problem.

When I wrote the first Avisynth script verbatim from the quickstart guide you referred me to (for just the video) it opened fine in VDubMod.

But, when I wrote the second script (for both audio and video), and attempted opening it in VDubMod, I got this error prompt:

Avisynth open failure:
Script error: there is no function named "AC3Source"
(C:\Documents and Settings\user1\My Documents\DVD Decrypter ISO IFO VOB Files\myvob.avs,line 3

What went wrong?

EDIT: BTW, I highly doubt you'll need these; but I'll add them anyway in the event I made a script typo.

Script 1

LoadPlugin("C:\Documents and Settings\user1\Desktop\dgmpgdec149\DGDecode.dll")
MPEG2Source("myvob.d2v")

Script 2

LoadPlugin("C:\Documents and Settings\user1\Desktop\dgmpgdec149\DGDecode.dll")
video=MPEG2Source("myvob.d2v")
audio=AC3Source("myvob.ac3")
AudioDub(video,audio)

[neuron2]

Get NicAudio here:

http://nic.dnsalias.com/nixaudiostuff.html

Then you will be able to use:

video=MPEG2Source("myvob.d2v")
audio=NicAC3Source("myvob.ac3",2)
AudioDub(video,audio)

Say thanks to Nic. :)

[DFF]

I downloaded/extracted the files but it's still doesn't want to work.

Now I'm getting:

Avisynth open failure:
Script error: there is no function named "NicAC3Source"
(C:\Documents and Settings\user1\My Documents\DVD Decrypter ISO IFO VOB Files\myvob.avs, line 3)

[neuron2]

Did you load the DLL?

LoadPlugin("NicAudio.dll")

Or did you place it in your Avisynth plugins directory?

[DFF]

I looked over that 'read me' guide and am still at a loss.

I'm green with regards to writing scripts and the lingo that goes with them.

As such, I don't know where to add what.

So, if you could please show me how this template of yours would look with the Nic modifications tacked on, then I would understand, since, we do know how to copy n' paste. lol

LoadPlugin("...\DGDecode.dll")
video=MPEG2Source("myvob.d2v")
audio=WAVSource("myvob.wav")
AudioDub(video,audio)

[neuron2]

Here's the basic idea:

LoadPlugin("...\DGDecode.dll")
LoadPlugin("...\NicAudio.dll")
video=MPEG2Source("myvob.d2v")
audio=NicAC3Source("myvob.ac3",2)
AudioDub(video,audio) And here is the same thing but with a delay correction of -128 milliseconds (you get the delay from the audio filename):

LoadPlugin("...\DGDecode.dll")
LoadPlugin("...\NicAudio.dll")
video=MPEG2Source("myvob.d2v")
audio=NicAC3Source("myvob.ac3",2).DelayAudio(-0.128)
AudioDub(video,audio)

[DFF]

I tried using NicAudio, both with, and without the delay, and neither worked.

I got this error prompt when I tried loading my Avisynth file into VDubMod:

Avisynth open failure:
m2AudioAC@Source: unable to open file "myvob1.ac3"
(C:\Documents and Settings\user1\My Documents\DVD Decrypter ISO IFO VOB Files\myvob1.avs, line 4

Then I went back to DGIndex, reloaded my VOB, checked 'decode AC3 track to WAV', then tried opening this second Avsynth script and VDubMod gave me this:

Avisynth open failure:
AVIFileSource: couldn't open file 'myvob.wav'
(C:\Documents and Settings\user1\DVD Decrypter ISO IFO VOB Files\myvob.avs,line 3)

[neuron2]

You've got some kind of path problem. Give us your exact scripts.

[DFF]

NicAudio:

LoadPlugin("C:\Documents and Settings\user1\Desktop\dgmpgdec149\DGDecode.dll")
LoadPlugin("C:\Documents and Settings\user1\Desktop\NicAudio\NicAudio.dll")
video=MPEG2Source("myvob1.d2v")
audio=NicAC3Source("myvob1.ac3",2)
AudioDub(video,audio)

WAV:

LoadPlugin("C:\Documents and Settings\user1\Desktop\dgmpgdec149\DGDecode.dll")
video=MPEG2Source("myvob.d2v")
audio=WAVSource("myvob.wav")
AudioDub(video,audio)

[neuron2]

Try using full paths for your D2V and AC3 files if they are not in the same directory as the AVS script file.

[DFF]

All are in the same directory. I tried adding the paths anyway to see if helped. No dice. I'm still getting the same error prompts.

[neuron2]

It works for thousands so I'd have to guess it's pilot error. Since I'm not sitting right there to see what you're doing, it's difficult to help you. Recheck everything, being very careful about file names, paths, etc.

[DFF]

Well, I've tried multiple times and keep getting the same errors. Everthing's kosher in terms of directory's and paths. They're right where they should be.

When loading only the video in VDubMod (after being processed through DGIndex), I noticed there was an odd blurring effect going on at times. When objects moved, there were these line like tracers left behind and on them. It appeared the frame rate was off, although I didn't tinker with any of the frame rate settings on DGIndex.

Perhaps this could be a clue as to what's causing my audio woes?

Anyway, if I can't resolve these issues using DGIndex/DGEncode/Avisynth is there another way to demux then sync inside VDub?

Thanks.

[foxyshadis]

"same directory" is pretty meaningless in avisynth, where any number of things can change the current folder out from under your script - the host application, plugins, and so on. Always specifying full paths is much simpler.

There might be some kind of weird corruption going on with the audio. I can't help there.

[DFF]

When I open the VOB in VDubMod, both video and audio play. The audio's great...cept' for that little 'sync' issue of course.

Anyway, this stuff's about to drive me out of my mind. I know I'm like this [-] close to getting it right but just can't seem to get over the hump.

As such, I've come to the realization I need a break. A long break. I'll see you guys tommorow. lol

[DFF]

M'kay...I'm ready to take another crack at this so here goes.

Since I was having difficulties with the DGIndex/DGDecode/Avisynth amalgam, I was going to to attempt a different route -- demuxing my VOB in DGIndex then in lieu of writing an Avisynth script for both video and audio, just doing one for video, then opening my WAV into VModDub, and there, syncing it together with the video.

So my question is: how do I sync them both inside VDub?

BTW -- two things 1)the framerates from the DGIndex videos I'd created before looked 'off' once inside VDub; there was a lot of what appeared to be tracing going on 2)whenever I open a VOB fresh from DVD Decrypter directly into VDub; I
have both video and audio.

From what I've gathered, I shouldn't have audio though, just video. Therefore, if this is true, will it conflict with what I'm now attempting to do? Thanks.

[neuron2]

So my question is: how do I sync them both inside VDub? Audio/Interleaving/Audio skew correction.

BTW -- two things 1)the framerates from the DGIndex videos I'd created before looked 'off' once inside VDub; there was a lot of what appeared to be tracing going on What do you mean by "tracing"? Get the frame rate from File/File information. It can't be 'off' unless you change it in your Avisynth script, or unless you use Forced Film in DGIndex.

2)whenever I open a VOB fresh from DVD Decrypter directly into VDub; You can't open a VOB in VirtualDub. Do you mean VirtuaDubMod or VirtualDub MPEG2? Be precise; it can make a difference.

I have both video and audio.

From what I've gathered, I shouldn't have audio though, just video. Therefore, if this is true, will it conflict with what I'm now attempting to do? Maybe you used VirtualDubMod? Use VirtualDub MPEG2 and I believe you won't have that issue.

You need to be aware of pulldown (RFF) flags and how the VirtualDub variants handle them. If you have irregular pulldown (e.g., your stream is hybrid film/video) and you use VirtualDubMod, you are almost guaranteed to have sync problems.

In VirtualDub MPEG2, you can control how RFFs are handled using Options/Preferences/MPEG.

So to continue guiding you properly, we need to know if the stream has soft pulldown. Load the VOB in DGIndex, set Honor Pulldown Flags, and do a preview. Does the count in the Field repeats box of the Information dialog increment? If so, you have pulldown. If the pulldown is regular 3:2 then you should do IVTC. That will not be a fun thing to do in VirtualDub.

IMHO, you gave up too soon on your earlier approach. You need to be persistent and get to the bottom of things.

[DFF]

What do you mean by "tracing"?

I didn't check force film or make any other changes.

I just opened a VOB in DGIndex, pressed play; and the film looks crisp and sharp. When objects make sudden movements though, there's this tracer like effect left behind them with lines around the edges.

The best way I can describe it, think a 'hippie' waving a lit cigarrete lighter around. Sort've a hallucinogenic type effect.