On 7/19/20, Steinar H. Gunderson <steinar+ffm...@gunderson.no> wrote: > On Sun, Jul 19, 2020 at 08:20:40PM +0200, Paul B Mahol wrote: >>> If you can explain what you mean the difference between radial and zoom >>> blur >>> is, it would probably be possible to adapt the idea. >> That algorithm is very slow for big lengths, it takes ages to process >> single small image. > > Yes, this is the non-recursive version, which is O(n) in the number of > samples. This is why I recommended the recursive version, which is O(log n) > in the number of samples and thus avoids the problem with big lengths. > It is fairly straightforward to convert one to the other.
Really? How so? > >>> It also has a somewhat more efficient implementation of bilinear >>> filtering >>> than in your patch (three multiplies instead of eight, and also fewer >>> add/sub), although it's likely that a fixed-point implementation would >>> save >>> yet more time if you're interested in trying that. >> Such micro-optimizations could be added any time later. > > Sure. > > /* Steinar */ > -- > Homepage: https://www.sesse.net/ > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > https://ffmpeg.org/mailman/listinfo/ffmpeg-devel > > To unsubscribe, visit link above, or email > ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe". _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
