Bad video playback

[BarnyGeroellheimer]

Hi,

I have a problem with a ATI Rage 128 Pro.
When playing divx-movies, I have big blocking artefacts in dark areas of the video.

Is this a general problem of this gpu?

Running:
windows 98se
ATI driver V6.65
DirectX 8.1
512 MB RAM
P4 1600
ms media player 6.4
media player 6.4 classic

desktop resolution 800x600 16Bit
video resolution is multiple of 16.

movie as codes with divx 5.02 pro (only bframes activated, no other pro features). Same codec used for playback.

Cheers,
Barny

[avih]

probably it's NOT a problem with the display card.

you could try changing the desktop resolution or changing the color depth of the desktop (i.e. move to 32 bpp).

of course, it could also be a poorly compressed clip. compression DOES introduce atrefacts, as it's NOT lossless.

[BarnyGeroellheimer]

Changing resolution or colordepth has not effect.
The movie is in perfect quality. I coded it myself, and if I run it on my PC or any other, the video looks really great. Only the machine with the ATI board has that problems.

I also tried a PIII 450 MHz with an integrated Intel 820 graphic-chip, which is not very powerfull at all, but even this gpu does perfect and smooth playback.

It's not only one movie that has that bad playback on the ATI chip, it's a general problem. All movies have that blocking effects in dark areas on this PC.

[Kb_cruncher]

I Wouldn't overlook trying a different video card.I have an ati rage mobility(4mb,64bit).@ 32bit colour it plays back video less than adequitly,@ 16 bit colour its a little better but not much.The computer i just upgraded from had a voodoo3 2000 onboard with 8mb memory and it played everything i thru at it flawlessly and very crisp(artifact free).before the ati i have had a GF2 and a matrox G450.i encode mostly mpeg2 svcd and all cards bar the voodoo have very bad combing artifacts @ 352*576 and less(pc monitor only,not tv).I never had this problem with the voodoo so i bought a v3 3000 to test if i get the same artifacts.if i don't then i would say a voodoo is the card to get,especially for monitor playback.the old voodoo was on an intel bx440 mobo,i am know running an ALI chipset but i got the sane artifacts on a VIA aswell.so the chipset could be a factor too.i will let you know the results once i have tested the voodoo.

sorry for the rant,hope this helps

[Kb_cruncher]

Installed the v3 3000 and my theory was correct.I encoded a vcd and it is absolutly cristal clear and sharp as a tac,no combing artifacts what so ever.if you can get hold a a voodoo3 i would highly recomend it,especially if you are running an AMD cpu,as they have brilliant support for 3DNOW.

[Zhnujm]

are you sure these artifacts are not only caused by different brightness/gamma settings of your overlay ?
you wouldnt believe how much more artifacts you see in dark scenes if you only increase the brightness a little.

[Kb_cruncher]

definatly not.as i said before i have tried a number of cards and infinate settings(including powerstrip tweaks)and all the cards bar the voodoo gave me these arifacts.once i put another voodoo3 in my machine all my problems went away.