...from the great open source tool : GIMP. Avery lee explain how it works on his website (vdub's website). Donald made after a second version, optimised for avs. for technical information, read the source code :p
donald > Avery Lee did, i know ^^ i use your version into avs, thks you ^^ do you make a new version in the future or wait avery's new version ? 1000 thks for your new decomb :) :) :)
i did implement warp-sharp some time ago (xvid postprocessing) with avree's help. it's a genious filter (i also got a pdf explaining it, don't know if i still have it). what it does is morph the image such that it 'condense' the areas of luminance transitions. this way the transition area becomes thinner, and hence sharper. but it doesn't introduce noise in the process, since it's not convolution, it just 'rearrange' the [sub]pixels such that the edges are shrinked -> sharpened. pretty amazing imho ;)
@avih Thanks for the links, I hope I'll understand ;) ;) @MarcFD Don't know of I'll code it, I was just curious about the algo. And I'm sure I got no time to do it in the next 2 weeks. If milan add it in ffdshow (in YUV2) it'll be easy to port it in avisynth. I'll check that with milan.