BTW, today I try ffavisinth at first time and found that "option" parameter does not work with examples provided with avisynth offline doc. I discover that small problem was a space around of comma delimiter. ffdshow(options="isLevels=1, levelsMode=0, levelsGamma=1500") # does not work ffdshow(options="isLevels=1,levelsMode=0,levelsGamma=1500") # works fine