Add audio track to DVD = introduce delay?

[andru123]

Hi,

I wanted to create a backup copy of a Jungle book DVD, but with extra language track, so my daughter could learn another language.

I demuxed a DVD, prepared extra language track as ac3, started a muxman, entered all information, remuxed - and ... the resulting DVD has audio about a second earlier that the original :(

The PgcDemux said there is 0 audio delay.

Now, I can understand the physics (I think) - the video and audio data is split into cells - so each cell contain a piece of video and audio streams. When I add extra audio, each cell will contain a little less of each stream - but apparently muxman doesn not do it proportionally - so the delay is introduced.
Am I right? Is there a way to figure oout the new delay, so i can fix it?

[blutach]

It depends on the timings in your newly prepared audio track. Are you sure they match exactly? The other audio tracks should remux perfectly but if your new track is not quite right, there may need to be a delay introduced (note - it can not be more than 300ms).

When I add extra audio, each cell will contain a little less of each stream - but apparently muxman doesn not do it proportionally - so the delay is introduced.
This is incorrect - the VOB container doesn't have a fixed space. The demuxedf bits will remux to the same size and your new track will add to the size. But each track has its own timing.

Regards

[andru123]

unfortunately, even if i just mix the original video and audio tracks back (no new stuff), there is still a delay. :(
I checked the length of the audio and video, and audio appears 1.02 sec. shorter. Unfortunately, muxman, does not allow for delays fore than +-300 ms. Otherwise I would just try that. Is there any other way to mux stuff?

Also, there are like 23 frames of blackness in the begin. (for ~224 ms, according to DGIndex). I tried to muxman it with both -224 and +224 delay of audio track, but both times it was still noticable off.

I tried to look into the VOB files to figure out where the sound begins in the original vob, but I could not interpret System reference time in seconds. I could see that in the original and new VOB the audio appears at different times, but, again, I could not convert it into ms. of delay that I need.

[r0lZ]

Use DelayCut (http://jsoto.posunplugged.com/audiotools.htm) on your new audio track before muxing it.

[blutach]

And how did you demux? Use PGCDemux to get the streams. I am puzzled how remuxing the original streams can itntroduce delay where one was not present before (unless the demux was no good).

Regards

[andru123]

I did use pgcdemux following these steps: http://forum.doom9.org/showthread.php?t=140026&highlight=add+audio+track+dvd It produced a nice set of A/V streams and celltimes.txt.
i also used that button to check the delay, and it showed 0 ms for everything.
I also tried delaycut, but ... I dont know what delay to put there :p I tried +1000, -1000, +400, -400, waiting for muxman to re-encode everytime, but none of the combination was good - audio was either too soon or too late. Again i tried only with the original english track of the original dvd - no extra audio track

[blutach]

The original streams shouild require no delay. Dunno what's wrong.

Regards

[r0lZ]

Being a Disney DVD, Jungle Book is probably protected by RipGuard. I suppose that there are bad timecodes in the protected cells at the beginning of the PGC., and perhaps dummy cells with no time codes at all Try to remove the first short black cells with PgcEdit, then remove them from the VOBs with FixVTS or VobBlanker.

[manono]

Being a Disney DVD, Jungle Book is probably protected by RipGuard. I suppose that there are bad timecodes in the protected cells at the beginning of the PGC., and perhaps dummy cells with no time codes at all Try to remove the first short black cells with PgcEdit, then remove them from the VOBs with FixVTS or VobBlanker.
Yep, that's almost certainly the reason - an improper decrypt. If you just want to fix the delay and remux, play the out-of-synch VOB in Media Player Classic Home Cinema and use the +/- keys on the keyboard to adjust the delay in real time. It'll say how much of a delay you've set in the bottom left of the player. Once you've got it figured out then use that figure in DelayCut.

[Ghitulescu]

The original streams shouild require no delay. Dunno what's wrong.

Regards

There are DVD I own (I don't remember now their names) that do have audio offsets (delays). And I always wondered how to input negative delays in IFOedit :scared:

[Ghitulescu]

Hi,

I wanted to create a backup copy of a Jungle book DVD, but with extra language track, so my daughter could learn another language.

I demuxed a DVD, prepared extra language track as ac3, started a muxman, entered all information, remuxed - and ... the resulting DVD has audio about a second earlier that the original :(


Just a remark:
Are you sure that the newly introduced audio track (which according to the red paragraph seems not to come from the same DVD) matches the DVD you have?
I think there are many editions of Jungle Book, at least here in Germany. And there are the NTSC variations too.

The DVD do not match may be because:
one has more introductions (logos, warnings)
is in a different tv-standard
the ripper picked a different starting point

[r0lZ]

Plus:
- the movie is ARccOS/Ripguard protected and contains additional dummy cells at the beginning.