On date Sunday 2014-11-02 13:28:05 +0100, Michael Niedermayer encoded: > On Sun, Nov 02, 2014 at 09:09:51AM +0530, arwa arif wrote: [...] > > The reference code I used was "https://github.com/carlosascari/2xBR-Filter". > > I see, and i understand now where the abs bug in your code came from > i dont think this was a good choice as reference > Its readme even says: > Research: Hyllian mentions a few optional implementations besides level 2 > interpolation, but i can't find any documentation on the filter other than > the byuu forum, where he only mentions them: > Font Enhancement > Using LVL2 Interpolation in regions plagued by shades of colors > Using linear equation of the Straight Line to interpolate in odd > scale factors > > so it seems to me the reference used was not a complete implementation > of xBR > > does anyone have the actual sources of the original xbr filter ? > i did find some links but they all just redirect to some spy/add/crap > ware download-manager > > also i found an example on how one of the reference pics should > look with 2x xbr on: > http://forums.getpaint.net/index.php?/topic/23601-2d-image-scaling-algorithms/page-2
This is the link mentioned by ubitux: http://filthypants.blogspot.it/2012/03/xbr-vs-hqx-interpolation-filter.html in ticket: https://trac.ffmpeg.org/ticket/3404 This blog mentions Hyllian xBR algorithm: http://board.byuu.org/viewtopic.php?f=10&t=2248 but the link above is dead. Googling for Hyllian and xBR I found this Hyallian's repository: https://github.com/libretro/common-shaders The forum mentioned by Michael: http://forums.getpaint.net/index.php?/topic/23601-2d-image-scaling-algorithms/ is about a Paint.NET Plugin: http://code.google.com/p/2dimagefilter/ A short description of xBR is here: https://code.google.com/p/2dimagefilter/wiki/ImageScaling#xBR Since Hyllian code seems to be mentioned for the first time in relation to byuu (a SNES emulation project), I looked for: http://byuu.org/ I downloaded the higan (name of the SNES emulator) code, and grepped for xBR but with no luck. So at the end I was not able to find a C reference for xBR. Probably we should contact Hyllian himself to get advice about a (possibly C-language) reference implementation. Comments/insight are welcome. -- FFmpeg = Faithful Furious MultiPurpose Enhanced Geek _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel