Weird decoding using 17022003

[sungey]

i have a clip

http://www.rpi.edu/~ismael/clip/weird-xvid.avi

I'm not pretty sure which build was used to encode this clip, but _most_ likely it is xvid stable.

Using 17022003, i open in vdub... play the clip slowly (using right arrow button) i can see horizontal lines slowly appearing on the
woman's yellow hair.

It doesnt happen with Koepi's xvid stable.

Anyone has any idea about this problem ?

[cult]

the lines dont show with the latest nic's decoder,but they are there with ffdshow

[AS]

Originally posted by cult
the lines dont show with the latest nic's decoder,but they are there with ffdshow

Indeed, I can reproduce the same thing on ffdshow. I am decoding with umanias'c 12/2/2003 build and no problems there.

[Blueseb]

Originally posted by cult
the lines dont show with the latest nic's decoder,but they are there with ffdshow
i confirm that, but i selected idtc xvid in ffdshow properties and lines disappeared. thre's a little description in miscellaneous tab, maybe it's a known issue

[cult]

with which idct they didnt show in ffdshow?

[CruNcher]

Xvid and Normal - no artifacts
Simple and Reference - artifacts

A description for that problem stands under the dropbox

Quote from FFDSHOW

IDCT
If you see periodically appearing faint horizontal lines in the movie or colors are slightly changing, try to select different IDCT routine
Following descriptions are based only on some users experiences, you may obtain different results.
Simple 16383 - this is preferred routine, it's fast and quite accurate, but may produce some artifacts with DIVX 4,5 and XVID movies
Normal - slightly slower than above and may produce horizontal stripes with DIVX 3
Reference - most precise, but very slow - it is usable only for testing
Simple 16384 - older version of Simple 16383, it's deprecated now
XviD - IDCT routine from XviD decoder, good for DIVX 4, DIVX 5 and XVID movies

[sungey]

hmm could it be 17022003 build doesnt use Xvid IDCT ?

[CruNcher]

So the problem is with what IDCT you encode its best to decode or you might get errors like the one mentioned above

CVS (Umaniacs) = Xvid IDCT <- probably gets changed in the future to Simple

Koepis = Simple IDCT

and there the problem beginns if you get a XviD from someone else and you don't know with wich IDCT it was encoded you hve to trail and error first and don't say XviD is buggy ;)

[sungey]

nah .. that's not a bug .... but now i know koepi's dev build doesnt use the same decoding routine as the stable build .. that's news for me :)