Audio offset issues

[phelix]

First off, excellent program.

I use SVCD2DVD to make DVDs of videos ripped from a PVR. Each video has a different offset. So, I have been trying to find ways to preserve that offset in the final DVD. To that end, I have been manually remixing my mpegs with mplex before feeding them to SVCD2DVD. Unfortunately, I have descovered that SVCD2DVD is screwing up the offsets.

Before I begin, I should say that I'm using pvastrumento to read the offsets of mpeg files, and Vobedit to read the offsets in VOBs.

I've discovered two problems. First, the version of mplex that ships with SVCD2DVD has a bug with audio offsets. On some files it is off by a frame or two. I have compiled my own mplex from the latest stable release of mjepg-tools (1.6.1.90). This version did not exhibit problems. A recent thread on the mjpeg-users mailing list confirmed that this is a known bug with older versions of mplex.

Second, after running some tests, I have discovered that SVCD2DVD itself is adding an additional offset (up to 100 ms) beyond what mplex is doing. This occurrs regardless of what program is used to mux the files. For me, it is affecting about 50% of the videos I'm processing. I have no idea why some files are affected and others aren't.

I'll PM you with a location where you can download the sample files and my test results, including offset measurements and SVCD2DVD log files. Here's one set of test results as a teaser. The numbers are how much the audio offsets are off by:

        sample1 sample2 sample3 sample4
test2         0     100      50       0
test3       -33       0     -16     -33
test4       -33       0     -16     -33
test5         0     100      50       0

[phelix]

Bump!

Any progress on this issue?

[ChrissyBoy]

I will look into it as soon as i can.

[phelix]

AN update...

The new mplexwin32 works fine. It now produces correct offsets. However, svcd2dvd is still adding additional offsets to the final vobs the same as before.

You got this problem 50% fixed. Good work.