BicubicResize (b=0, c=something>0.75)

A long time before it was discussed by Steady. You have to set: b + 2*c = 1 !!! That gives the most numerically accurate filter. Default setting b=1/3, c=1/3 satisfies this formula. Catmull-Rom spline b=0, c=0.5 is my suggestion for sharpness. In general: Select c for sharpness, then use b = 1 - 2c From c>0.6 the filter starts to "ring". You won't get real sharpness, what you'll get is crispening like on a TV set!

So, If c = 5, I must set b to -9 (1-2*5) in order to get accurate filter effect, is that right? I'll try it later. Thanks for your explaination. By the way, I don't care about ringing that much since it's not that noticable when watching from an appropriate distance. Have you encoded a movie using 100% quality-based method at full resolution, along with Vdub's sharp filter at maximum strengh (64)? I was totally shocked when I first saw the result. Someone may say "those details are fake", but at least they fake it beautifully. It's like you're watching a 3-D movie.

Oh NOO. No negative values: Then stay on B=0. You can cripple your pictures as you want. There are more nice filters to do such things like smoothing, sharpening... :) But BicubicResize has basicly to maintain the picture quality without visual effects. From bad sources you'll never get best results.