Xvid append problem: "...opaque codec data byte 14..."

[shae]

Trying to append two AVIs in VirtualDub I get an error message saying "Mismatch detected in opaque codec data at byte 14 of the format data".

I can play with the encoding parameters of one of the files, but not the other. Any idea what might this byte 14 be? It's not a packed bitstream problem, and I hex edited the frame rate to match (one was 23.976, the other 23.97621...).

[unskinnyboy]

http://forum.doom9.org/showthread.php?t=119181

Also, this is a VirtualDubMoD problem, not an XviD problem. Wrong forum.

[shae]

I read that thread before posting, but changing the colorspace didn't help. I now tried again with more colorspace types, and this time worked; YV12 was needed. Strangely, this is the very first colorspace I tried before... I suppose something got reset along the way.

As for posting under XVID, I wanted to know what byte 14 might mean, which is XVID (/MPEG4 ASP) specific. After getting it to work, I don't see any "byte 14" that is different, starting the count from various sensible positions, but I guess that might be a VD question. :)

Now that it stitches, is it certain that the stream is a valid XVID/MPEG4 ASP?

[shae]

Byte 14 is not XVID related after all. Turns out it's an offset beginning at a BITMAPINFOHEADER. 14 is biBitCount.

But now I'm getting complaints about byte 40, which is just after the size of a minimal BITMAPINFOHEADER, so this might be XVID... :) And now I'm stuck.

[shae]

In case anyone stumbles into this in the future, as I now understand, all these complains from VirtualDub are most likely not related to the actual video stream but to AVI headers (and possibly other junk?).

[Zep]

In case anyone stumbles into this in the future, as I now understand, all these complains from VirtualDub are most likely not related to the actual video stream but to AVI headers (and possibly other junk?).

well it is related to xvid in the sense that certain xvid settings seem to cause vdub to change avi header/index info. (as far as i can tell in my quick look into this) no i do not remember which settings but i ran into this when i encoded a 2 part encode and only changed a few settings in part 2 based on what i saw in part 1 encode to improve part 2 quality and when i later tried to append i received an error (error 14 also IIRC)

i set the settings exactly the same as part1 and re did part2 and then it worked fine.

good luck :)