On Fri, Nov 20, 2015 at 2:46 PM, Nikolaus Waxweiler <madig...@gmail.com> wrote: >> The filter is color-balanced, but not normalized. Values above 0x100 >> will have to be clamped and this non-linearity causes distortion and >> adds to color fringing. Stem darkening is the better way to increase >> contrast. > > > So I tried to find two values that sum to 0x100: > >>>> def f(a,c): > ... return [a - c, a + c, 2 * a, a + c, a - c]
I did some experimentation with my crazy patterns. I firmly believe now that simple box filter aka FT_LCD_FILTER_LIGHT is not just good but in fact the best in reducing color fringes IFF used with correct gamma. All color-balances filters with gamma eliminate color fringes completely, but the box filter is obviously the least blurry of them all. So I reached the same conclusion as this paper: http://scien.stanford.edu/jfsite/Papers/ImageRendering/Displays/Xu_Farrell_Matskewich_Wandell_final.pdf . Some day soon I will write a blog about the details of my experiments. _______________________________________________ Freetype-devel mailing list Freetype-devel@nongnu.org https://lists.nongnu.org/mailman/listinfo/freetype-devel
