BUG with audio delay and bit redistribution ?

[fjhdavid]

Dear all,

I tested two films with HC (profile best) and bit redistribution with AVS filters.

The two movies VOB's showed 0ms of audio delay (measured with DGindex 1.49 (last one)) before re-encoding.

After re-encoding, the VOB's show audio delay of +300ms and more which is a lot and start to be annoying.

Tomorrow I will try encoding with bit redistribution off (just to see it it is not an AVS filters consequencies) but I don't think so.

Did you notice the same problem?
thanks
Francois

[jdobbs]

The is no adjustment to the audio in DVD-RB -- it keeps the timing. I have received no other reports of anything even remotely sounding like this. The audio delays you see in DGIndex have absolutely nothing to do with DVD-RB (it doesn't use DGIndex).

If you are talking about the "Mobile Encoding" feature, the answer may be different -- but since you didn't mention that, I assume you are talking about standard DVD encoding. I noticed in other posts that you have been extracting audio and trying to reintegrate -- is that the case here? If so, that's probably the source of the problem.


I'm confident it isn't related to DVD-RB. Are you preprocessing or using filters

[fjhdavid]

in fact I just use DGindex like a tool in order to read the audio delay (which is, in the VOB, the difference between the PTS of the first audio packet and the PTS of the first video frame).

so my process is the following:

first: I take a film and I read with DGindex the audio delay.

second: without any work or demultiplexing on the audio track, I go with a dvd-RB re-encoding with HC encoder in "the best" setting.

third:after the re-encoding process I read the delay audio (with the same tools DGindex), and the audio delay has changed!

to be precise I also took a look into the VOB itself with VOBedit and the PTS has really changed. Is it a bug?

(during the re-encoding process I used AVS filters like ColorYUV to change the offset and Gain of Y, and a lanczosresize, that's all)

[jdobbs]

Nowhere have I received any reports of audio being out of sync except this one case (in fact, I'm not even sure whether you are saying so -- or that only the clock signatures are different)... so something different is happening. The fact that you get different values really doesn't mean anything -- it all depends on the multiplexing. They will keep the same relative values, however, because the audio/video follow the same clock.

The fact that you've indicated that you're trying to adjust the audio in other posts seems to indicate that you are manipulating something (maybe conversion in framerate?).