Audio out of synch using convertx to dvd.

[trueman]

Ive just used convertx to dvd to convert a avi file to vobs for burning to dvd. However the audio is way out of synch by a few seconds. The original file is fine but not the dvd Ive created.

Here is what gspot tells me about the original avi file.


4cc=XVID

Audio

0x0055(MP3) ID'd as MPEG-1 Layer 3

Bitrate 151 kb/s (75/ch, stereo) VBR Fs 48,000hz

Ive used convertx to dvd before wthout any problems.
Any suggestions.

[guns1inger]

VBR MP3 is the worst format for audio conversion. Even ConvertXtoDVD occassionally can't do it nicely, and it is one of the few than can do it most of the time. The only way is to strip the audio off using VDUB, saving it as an uncompressed wav file, then using this to replace the VBR MP3 audio in your AVI. ConvertXtoDVD can then process the video OK. You can also use CBR MP3, but this entails an extra compression of the audio - not recommended

[trueman]

I tried to strip out the audio using teh guide here.

https://www.videohelp.com/virtualdubaudio.htm

But I get an error message saying "ACM reported error on audio decompress (b)"

When I click okay a crash window is shown and then vdub shuts down.

Any ideas whats going wrong here?

[guns1inger]

I use Virtualdubmod. I answer yes to the error that VBR mp3 produces when the video loads. I then go Streams -> Stream List -> Right-click -> Full Processing Mode -> Right-click -> Compression -> Uncompressed PCM -> OK -> Save Wav. It never crashes on me.

Try Virtualdubmod. If it crashes, you have a codec problem.

[trueman]

That seems to be working.

Thanks for that.

[trueman]

Okay so now I have an avi file and a wav file.

What do I do next??? How do I replace the audio in the avi file with the wav file and then convert it to vobs with convertx to dvd??

Also for next time how do I know when I need to do all this or wehn I can just go directly to convertx to dvd? Isa it just a trial and error thing?

[guns1inger]

OPen the avi in virtualdub again. Streams -> Stream List -> add. Browse and select your wav file. In the Streams list, select the VBR MP3 audio track and select disable.

Make sure both video and audio are set to direct stream copy, and go File -> Save AVI. This should give you a new avi with the wav audio. It will be 600 - 800 mb bigger because wav take up more space. Run it through ConvertXtoDVD.

There is no way to predict what will and wont work. ConvertXtoDVD works 9 time out of 10. I usually do most of this manually, so I strip out the audio as a matter of course.

[redwudz]

To check a AVI for MP3 VBR audio quickly, I just drop them into the latest version of Gspot. Look below the audio window and there is a CBR - VBR indicator. Or drop them into VirtualDub. It will tell you immediately if it's VBR, then you can convert to WAV.

[guns1inger]

Virtualdub does the same job, but again, this won't tell you if ConvertXtoDVD will have a problem or not. Mostly it doesn't, and VBR audio remains in sync. Sometimes it chokes.

[DarrellS]

There is no way to predict what will and wont work.

Exactly!
Sometimes, all you have to do is put the uncompressed wave back into VDub and the audio is the same length as the video and perfectly in sync. Most of the time, for me though, the audio length is different and has to either be warped in Goldwave or silence added to the beginning of the audio.
I had a two part VBR XviD last week that took forever to get the first part in sync, the second part was fine, when I joined them, the first half was fine and the second half was out of sync.
It's enough to drive you crazy and cuss everyone that uses VBR audio. It's almost as bad as a computer virus that is spread across the internet like wildfire.

[guns1inger]

I have never found a VBR MP3 I couldn't fix by decompressing in vitualdub. Never had to stretch or compress the length. Must just be lucky.

[DarrellS]

I have never found a VBR MP3 I couldn't fix by decompressing in vitualdub. Never had to stretch or compress the length. Must just be lucky.

I've never seen one that I couldn't fix but some are easy and some are almost impossible.
I might not have to fix all of them, I don't know but I would rather find out before I spent 1 1/2 to four hours running them through DivXToDVD or burning them to a data disc which is what I usually do.

Like you said, it's hit and miss whether they'll work or not. I was able to fix 8 out of 10 files the last two weeks and the two I didn't fix were not worth fixing. If the files were encoded correctly, I would not have had to spent any time working on them at all and could have just burnt them to a data disc with Nero.

Editing programs like virtualdub, although not the cause are part of the problem since they are not capable of opening a VBR AVI correctly. Correctly isn't the right word since VBR audio is not meant to be in an AVI container. The files play fine in mediaplayer until you try to do anything with them so people who create them don't see a problem with them. They work fine on their computer but once they've gone out of their computer onto the internet, their is no telling how bad the file will get corrupted along the way.

[trueman]

To check a AVI for MP3 VBR audio quickly, I just drop them into the latest version of Gspot. Look below the audio window and there is a CBR - VBR indicator. Or drop them into VirtualDub. It will tell you immediately if it's VBR, then you can convert to WAV.

Okay Im stucka little bit here where you say "In the Streams list, select the VBR MP3 audio track and select disable"

In the "available streams window" I have Source input: avi file and Source input: my wav file
So I dont really have the mp3 audio track listed seperately.

What have I done wrong?

[guns1inger]

I use Virtualdubmod. Streams -> Stream List shows you all the audio streams in the avi file. One of these will be the original MP3 audio, which you don't want.

If you have managed to replace the mp3 file with the wav file some other way, don't sweat it, just move on.

[redwudz]

That's just some confusion about VD Mod and the regular VD versions. They have the menus set up differently. guns1inger was talking about VDM and I mentioned VD earlier. I would recommend VDM as it's a little easier to work with the audio. In VDM it's Streams>Stream list. Rclick on the MP3 audio and select 'Full Processing'. Then go to the lower right of the main window, click 'Save WAV'.

To put a audio back in, open the same 'Stream List' window. Select your new WAV or other modified audio by using 'Add'. Then Rclick the new audio to select and 'Move up' the new audio. Rclick the old audio and click 'Delete' that now shows to the lower right. Click 'OK' and close the audio window. Under 'Video', select 'Direct stream copy', and save the file. DivxToDVD will accept the new version with the WAV audio muxed in. If you deal with those kind of Xvids, you will run into this problem fairly often. It's not really that hard after you do it a couple of times.

EDIT: I see guns1inger typed faster than me.

[trueman]

Okay well I finally got the hang of how to do it...But That made it wors.

In the original avi file the audio is in synch, and only went out of synch when I converted it uisnf convertxto dvd and burnt to disc.

However the avi file I just created by stripping out the audio to avi and then putting it back in is actually worse than the dvd and the audio is even further out of synch than my dvd.

The audio is about 2 seconds in front of the video.

Did I do something wrong?

[trueman]

oh BTW Thanks for all the help you guys are giving.
Much appreciated.

[guns1inger]

Did I do something wrong?

Probably, but it should be easy to fix. Assuming, that is, that the movie is out of sync by a continuous amount the whole way through.

First, can you provide the following information

1. Running time of the video (File -> File Information)
2. Running time of the audio (File -> File Information)
3. File size of the wav file

Assuming they numbers in 1. and 2. are close (if not exactly the same), do the following

Streams -> Streams List -> Right-click on the wav stream and select Interleaving (if you are in Direct Stream Copy mode, it will be the only available choice). A dialogue will open with a section called Audio Skew Correction (lower half). In the field you can enter a delay in milliseconds to adjust the start point of the audio. Using negative numbers makes it start sooner, posative numbers make it start later. Put in a number, click OK, OK. You can now listen to the change you made by playing back the video. If it is still out, go back and change the number again. Do this until it matches, then save the avi again (video and audio in Direct Stream Copy mode). Everything should now be in sync.

[trueman]

Okay one question, am I supposed to be doing all this to the original avi file or to the avi file I created when I added the wav file?

Also when I check it bypressing play I get the following error message "Error decompressing video frame 0:

An unkonw error ocured, (may be corrupt data)(error code-100)

What am I stuffing up now???

[trueman]

Oh and yes the video and audio were different lenghts.

[guns1inger]

What were the lengths ?

Use the version with the wav audio, not the VBR MP3 audio

[trueman]

Video was 1:23:05.23

Audio 1:20:53.06

[guns1inger]

And the file size of the wav file you created ?

[trueman]

Oops...The wav is 888mbs.

Im still getting the same error when trying to play the video clip.

[guns1inger]

The numbers look OK. Try scanning for errors (under the Video menu in Vdubmod). Do you get this problem opening the original avi ?

[trueman]

I get the same problem trying to open the original avi as well and a few other avi's Ive downloaded from the net.

However I can play avis ive created myself with my video camera or my tv capture card.

When I scan for errors it doesnt find any.

[guns1inger]

I would try installing a newer version of the codec, or switch to avisynth and ffdshow, and open the files as DirectShowSource. Only catch - ConvertXtoDVD cannot open avisynth files yet.

[trueman]

Which codec? Im not sure which one?
xvid or divx or ffdshow codec? They are all the latest verisons anyway.

[trueman]

Here is a list of codecs I have installed.

http://www.trumanlive.com/images/Codecs.txt

[guns1inger]

Virtualdub doesn't use ffdshow. Your list doesn't seem to include Xvid, so it must be using Divx to decode them. Is this message appearing as the first frame, or as a pop-up dialogue that prevents you from playing ?