Strange aliased lines, maybe bad decoding

[Lefungus]

Hello, not sure if it's the right forum to post this

I'm using avisynth 2.5 to encode movies. Recently i experienced aliased output when i watch movies through avisynth. I've made two screenshots, one under media player classic using wmr9 (same output with overlay mixer), an other under virtualdubMod

I've made two PNG screenshots to show this behaviour ( nearly 300KB each)

VirtualdubMod output (http://perso.wanadoo.fr/reservoir/dl/Virtualdubmod.png)
Media player classic output (http://perso.wanadoo.fr/reservoir/dl/Media%20player%20classic.png)

Look at the windows borders on the background or at left bilbo's arm. The source is from a PAL progressive DVD, so i expect no interlacing artifact. I've no idea what could cause this?
I used a minimal avisynth script for the screenshots.

Mpeg2source("J:\Test.d2v",IDCT=5,CPU=0)
Is this bad decoding ? I tried different outputs like wmr7 and 9, overlay mixer. I tried others players like tcmp4.
These artifacts are even worse when playing. I'll be glad if someone can help me. Have i overlooked something ?

[sh0dan]

Perhaps your graphic card overlay is not support YV12, and therefore converts the video to RGB. You could try enabling "Raw Video" under codecs, and see which colorspace it is reporting as input/output.

[Lefungus]

My graphic card is a common geforce 4 ti 4200. In media player classic, the video renderer reports that it have hardware capability for YV12.

I don't know where i should seek "You could try enabling "Raw Video" under codecs"

i've tried to add ConvertToYuv2() and ConvertToRgb() at the end of the script, but artefacts are still there

[sh0dan]

Sorry - I meant "You could try enabling "Raw Video" under codecs in ffdshow."

[Lefungus]

Checking Raw Video under ffdshow have indeed solved my problems. No more artefacts. Info box tells it's YV12.

But i still don't know why it doesn't if Raw video isn't checked.

[Aktan]

unfortuantly, your "common" card from nvidia has overlay problems. Its due to nvidia's drivers in which well they didn't do a too good job on overlay, or so I hear. I think its especially bad with Windows XP too.