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aldaco12
29th November 2005, 10:03
Hi. I have this simple problem. I want to substitute the MP3 audio in have om my AVI with an AC3 audio stream I can rip from the same DVD I used when I made it. I think to use VirtualDubMod (Stream____Stream List; Add the AC3 + Desable the old one; [OK], set Video on Direct Stream Copy , Save as [F7]).

I can demux the audio traces in many ways from a VOB set (DVD2AVI if there's also the video), VOBEdit in any case...

My problem is this:
the file VTS_01 - Stream Information.txt shows that on the AC3 audio streams there's a delay of -80 ms.

[A strange thing: when I 'decode to WAV' the sound with DVD2AVI I never observed a delay (why?). I'm afraid now that I will]

So, the questions are:

1) how can you fix the A/V delay you know exists, when you want to make an AVI (on DVD authoring you simply add a 'delay' number, but here you can't)? If you have 'delay -80 ms' what do you have to set, and where?
Please note: I don't want to make again the AC3 file. I just want to tell VirtualDubMod to take the delay into account, if there's a delay (will it exist , such a delay?), Or , if there is not such a possibility, can I extact , from a VOB set, an AC3 stream which has 0 delay, I don't know, with ReJig or something else...

2) why, when you simply 'decode to WAV' an audio stream with DVD2AVI, you don't notice a delay? Is the 'zero delay' a feature which exists always on DVD2AVI or only when you 'decode' (and , when you 'demux' is noticed)?

frank
29th November 2005, 10:57
First, use DVDAVIdg or DVDIndex by neuron2. The old DVD2AVI has a bug that caused the -80ms delay.

If you rip from start then there are usually no audio delays.

DVD2AVI automatically cuts out the audio delay if you decode to wav.

jsoto
29th November 2005, 23:12
pgcDemux is also able to demux and gives you the right delay info (as frank said, usually zero. 80 msecs is the typical wrong data coming from the old DVD2AVI)
But, if you need to add a delay (i.e if your avi is a cut of the original DVD, taking away some intros) you can manipulate the ac3 stream with delaycut or with BeSweet, or with ac3delaycorrector. There are many free tools able to add/cut frames in an ac3 stream

jsoto

dialysis1
6th December 2005, 22:39
I found out the easiest way (for me) was to rip the dvd and let AutoGK do the rest.

setarip_old
7th December 2005, 03:53
I just want to tell VirtualDubMod to take the delay into account, if there's a delay
Hi!

After loading in your .AC3 audiostream, click on "Streams". Then rightclick on the .AC3 stream. Then click on "Interleaving". Then set "Audio skew correction" to the appropriate delay...