Quick tests of the over/under shooted kernel in real processing in avisynth (built-in sincresize to size*4):
T=2.7, downscaled 3 times to fit 0..255 range (without negative values illegal to integer 8-bit coding of typical video/images). Samples put by hand in ms-paint into image array. (16),1,31,89,31,1,(16) (in the right side of image, at the left is sort of sin^2 or gauss pulse without over/undershoots (16),46,89,46,(16). 800% screenshot of ms-paint.
Later loaded in avisynth with imagereader, scaled with sincresize to size*4 with max available taps=20 and displayed in virtualdub as 50% and 100% size. The undershooted pulse shows very good conditioned against ringing with visually sharper view. Ofcourse vertically it is unconditioned against any Nyquist limits becaue it is 1-dimentional test, so it do shows ringing vertically.
Last edited by DTL; 10th July 2020 at 10:21.
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