Try the 05.2003 version and the 09.2003, the 10/11 have a spline/lanczos resize bug with media files. Or u can simple download all and test all
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What filter setting u use and in wich direction? Wich render overlay or VMR9 and if u use zoomplayer did u try disable color settings?
U can also save cpu time by using the right decoder's and postprocessing filters.
some chart fastest decoder first (all with overlay and yvu modes, vmr9 is always more cpu intensive)
mpeg1/2 (aka dvd):
1: elecard moonlight decoder V2.1 or V2.2 Beta with disabled double precission IDTC
2: sonic cineplayer or TheaterTek decoder (newest release)
3: cyberlink PowerDvD (latest patch)
4: WinDvD (latest patch)
*note the elecard moonlight decoder also has there own postprocessor in the decoder
divx3/4/5:
1: ffdshow libavcodec and 3ivx decoder*
2: xvid decoder (Nic's last release ICL7 or xvid 1.0 beta3 ICL10)
3: elecard moonlight "nice pheratou" decoder V2.2 beta
4: org. divx 5.1.1 decoder -> has macroblocking decode bugs so better use 5.04/5 but those version have crappy slow postprocessor's
xvid:
1: ffdshow libavcodec and the latest xvid ICL7/10 releases both perform nice, also 3ivx has good speed.
For pure decoding the ffdshow libavcodec is the fastest, the xvid decoder also have the same speed.
If u take postprocessor speed into account 3ivx 4.5 has a very optimized postprocessor wich is superior to divx 5.04/5 and also 5.1.1.
FFdshow postprocessor just work in mplayer+dering settinsg since Nic's dering or mplayer deblock smooths/washes the hell out of the movie and u will loose lotsa details.
The deblock postprocessor included in Nic's 07/2003 or 1.0 Beta3 xvid decoder work very nice without loosing any details but the dering suck arse.
3ivx dering+deblock is oki but u loose some little details, for dering best is mplayer set to 150 in ffdshow but just dering, leave the deblock settings off, also dont use nic's dering in ffdshow!