DV AVI to MPEG2 -- Audio Sync problems: PLEASE HELP!

[pandeyrajiv]

Hi All,

I have this nagging problem that I cannot seem to resolve...It has to do with audio sync, but it is not your average type of problem -- here are the details:

I have captured a 28 min video to DV via my camcorder to a approx 6 GB file(this file has NO audio sync problems whatsoever!).

When I take this DV AVI file directly and convert to MPEG2 for SVCD, It all looks fine(NO Audio sync problems)...

HOWEVER,

Because the audio is not that great and gets worse when the uncompressed audio gets converted to MP2 quaility, I decided to save the audio from the DV file to a seperate audio WAV file...So now here is what I have:
1 6GB DV AVI file(complete with audio and video, all synched)
1 280-290 MB file WAV file *extracted* from the AVI, which I have cleaned up -- NR, Equalization, Normalization etc.

When I used TSunami MPEG encoder and specify the video to be the DV AVI and the audio source to be the cleaned up WAV file and convert it to a MPEG2 for SVCD, I get an audio sync problem that starts out OK, but midway it starts to detriorate to the point where around the 25th min, I have aboue a 1 second lag in audio vs video...

Please note, I have compared the length of the DV AVI file and he WAV file and there is no difference right up to the hundreths of a second...so one cannot account for the length of the two files to be the cause!

My question is:

Why is it that all is fine when I use the DV AVI file as the audio and video source, BUT I get audio sync problems when I use the DV AVI as the video source and the extracted and remastered WAV file as the audio source...

Any thoughts would be very much appreciated!

Thanks

[Tommyknocker]

I wish I knew what causes this problem too, but being a newbie, it is not for me to know at this juncture (hehe). That being said, the problem is call "audio drift" or "gradual audio synch"(sic), and is a well-known problem, with a well-known solution:

http://forum.vcdhelp.com/userguides/78944.php

Good luck!

[yg1968]

I have a similar problem. I am capturing from DV. The avi (DV) file is in sync but when I encode to mpeg-2, the sound gradually becomes out of sync. I was under the impression that this was not possible when capturing from DV. I am a bit surprised. I will try different settings. For example, I will try capturing a type 2 DV avi file (instead of a type 1). I will also try setting my audio at 32khz. I will try uninstalling the mainconcept DV codec. I am not sure why this would help but I can't think of anything else I can do. Changing encoders doesn't help.

[Mxjshaf69]

Try converting the first half, then the second half and then merge them together.

[yg1968]

There must be an easier way to avoid this problem.

[yg1968]

I solved my audio sync problems by using TMPGEnc. I also used the settings suggested by Decepticon in this thread.

http://www.vcdhelp.com/forum/viewtopic.php?t=104713&highlight=sync+encoding