Will DVD2AVI extracted PCM from AC3 solve my audio sync probems?

[rapjp2001]

Hi All,

Been researching this for a while now and cannot find a definite solution...

I have several standalone DVD recorder VOB's that I want to reauthor in DVDLab...I have noticed that if I demux the audio using DVD2AVI, I see in virtually ALL the cases an audio delay of some negative amount.

Now, before you stop right here and point me to that large thread on audio sync problems that points you to AC3Delay Corrector, please don't, I have read it a few times already...

What I have seen is that if you want to use the AC3 file, you can do some editing in AC3Delay corrector that can fix the problem, but it is NEVER exact...

Also, my reasearch has shown that DVD2AVI apparently "compensates" for the audio delay of the AC3 in the VOB PTS, so one does not need to worry about it in the PCM WAV file...

My question is -- I have not tried this a few times to be absolutely certain...

CAN I use DVD2AVI and decode the AC3 file from the VOB directly into a PCM WAV file
*and most importantly*
WILL this demuxed PCM WAV file solve all my audio sync issues of the original AC3 in my authoring program (like DVDLab)???

Last point: I am very fine with using PCM WAV in the final authored disc over AC3, so don't worry about the high bitrate issues (1536 kBps)...I am cool with ALL that if my audio sync problem is resolved by using the DVD2AVI decoded WAV file...

Please help!

[oddyseus]

There is someone that have done it already by now and eventually he will show up and confirm your thoughts ... or not. :) In the mean time wouldn't be a more logical step to try this out and report to the community your findings?

Just a thought ;)

[rapjp2001]

Well, so far I have tried a few samples and it looks ok, but that could also be because the audio delay in the AC3 was quite small and hence incomprehensible to the eye...

I was hoping for someone else to confirm this at a mathematical level that DVD2AVI *does* in fact compensate always for the delay in the PTS and so it is a safe method...rather than the eyeballing approach...

I am just trying to substantsiate what I have read and seen a few times by someone...Perhaps at the level of Mpucoder or the likes...

[auenf]

or you can use besweet to decode the ac3, adjust based on a delay, and encode back to ac3 in the one step (altho ac3 files created by besweet/azid can sometimes not be accepted by authoring software, you can output to wav and encode in a different program later)

Enf...