ac3 desynchro with DVD2AVIdg

[freelock7]

I encode MPEG2 with the excellent QuEnc0.51 and the DVD2AVIdg mpeg2dec3dg.
First, I have some problem with Ac3 demuxing with DVD2AVIdg:Ac3 is corrupted with many desynchro DTS.
HAKO504 says in his thread:
"Demuxing can be done in DVD2AVI, but this will generate a number of files called Track01 DELAYxxxms.ac3 NOTE:This delay value has changed when you use DVD2AVIdg compared to older versions. Always use DVD2AVI to demux audio if you use DVD2AVIdg".
Is it right that DVD2AVIdg create bad AC3 data file?


Second,I have two .d2v (one created by smartripper; the other by DVD2AVI1.77) from the same movie but with two different sizes.
What does it mean?
Thanks for help.

[Guest]

Originally posted by freelock7
First, I have some problem with Ac3 demuxing with DVD2AVIdg:Ac3 is corrupted with many desynchro DTS. We need a better problem description. What do you mean by "many desynchro DTS". Let's stick with one file. What exactly is the nature of the desync you see? Can it be repaired by shifting the entire audio? Does the async get increasingly larger as the file plays? Or what?

Have you tried it with the latest software, i.e., DGMPGDec 1.0.12?

Second,I have two .d2v (one created by smartripper; the other by DVD2AVI1.77) from the same movie but with two different sizes. What does it mean? It means they use different D2V file formats.

[freelock7]

Thanks for answer.
i'll try dgmpegdec.
Follow up soon.

[Guest]

Why didn't you answer my questions regarding the nature of the desync?

[freelock7]

The problem appeared after demuxing complete VOB DVD files (STAR WARS 1&2).
DVD2AVI mentionned a delay-80ms (but there was really about -3000ms to correct).
After that <IfoEdit> refused to mux the encoded m2v and Ac3 ('corrupted audio data').
<Delay cut> from DRPenc was able to fix the errors (multiple A/V desynchro) when I choose
the option 'fix CRC errors'.
Muxing released, I saw the movie with no audio problem excepted at the end of the movie generic (many audio repetition).
Hope it can help you to find out.

[freelock7]

More details...



1)AC3 extraction by DGIndex.
Remuxing AC3/M2v create this in IFOEdit at the beginning:
STREAM EO: data will arrive too late. Current SCR3941958, stream DTS:0
STREAM EO: data will arrive too late. Current SCR5147954, stream DTS:0
STREAM EO: data will arrive too late. Current SCR6329651, stream DTS:0
STREAM EO: data will arrive too late. Current SCR6467958, stream DTS:0
STREAM EO: data will arrive too late. Current SCR7947457, stream DTS:0
----
Until that point A/V have a correct delay and IFO created can be listened.
But at 84% IFOEdit says:
INTERNAL ERROR:ADDITIONAL DATA REQUIRED BUT NO FREE SPACE IN INPUT BUFFER!
TOO MANY FRAMES DROPT!
--------------------------------------
2)AC3Cut after correction:
Time 00:11:38.464; Frame#= 21828. Crc1 error FIXED: read = C9A7; calculated=3E0D
Time 00:11:38.464; Frame#= 21828. Crc2 error FIXED: read = BBE4; calculated=9BF9
Time 00:11:38.496; Frame#= 21829. Unsynchronized frame...SKIPPED 1568 bytes. Found new synch word
Number of written frames = 210903
Number of Errors= 3
Even with this fix, unable to mux more than 85%.
So, I Have to demux the lastVob (VTS_01_4) and encode with QuEnc once again. My surprise when I see the AC3 file from this Vob with a DELAY -40ms.
No problem to mux this one with IFOEdit at Oms.
My conclusion:
Why each Vob has a different delay compared to the entire Vobs demuxed (no delay)?
Why each vob AC3 works properly with IFOEdit muxing and the entire Vob AC3 not?
It will be more easy to demux each vob AC3 and encode each one separately -but won't be practice.

[RB]

Originally posted by freelock7
The problem appeared after demuxing complete VOB DVD files (STAR WARS 1&2).
Did you rip these VOBs in File or ISO mode? If so, in most cases you can't just load these VOBs into DVD2AVI and expect the extracted audio and video to be "usable". Most of the time the VTS contains multiple PGCs, Angles and playback discontinuities etc.

For instance there may be two PGCs, originally composed from two different A/V tracks in the authoring software. When you load this multi-PGC VOB into DVD2AVI, the extracted audio will be "corrupt" (missing sync word) at the place where PGC1 ends and PGC2 starts.

I'd suggest you use something like the Big3, DVD-Rebuilder or DVD2SVCD for your DVD backups or make sure you rip in IFO mode when all you want is a movie-only backup.

[freelock7]

the VTS contains multiple PGCs
Thanks RB for this suggestion.
DVDdecrypter shows that in the <stream processing> option.
I'll always use it!:)

[Grafdude]

In my case, I have a movie which has 2 PGCs, and when I demux the audio it will generate 2 ac3 files, how can I join them together and have a perfect sync?

I noticed that my movie will get out of sync immediately after the 2nd PGC kicks in, so that means when DGIndex extracted the ac3, it did not properly synchronize the 2nd PGC with the first one.

Any suggestions?

[Guest]

DGIndex does not support multi-PGC or multi-angle VOBs. It is unlikely to do so in our lifetime. Please follow RB's advice.