[FFmpeg-devel] swscale : add bitexact conv for grayf32 and gray16 to f32 conv

Martin Vignali martin.vignali at gmail.com
Mon Sep 10 20:57:42 EEST 2018

> does the LUT generation code produce different results on platforms ?
> if so i would suggest to try to use double and to add a small offset if
> needed
> a 8bit table has 256 entries, a 16bit table 65536
> a difference would occur if a source value from 64bit floats gets rounded
> differently to 32bit floats. If this occurs a small offset could be added
> so that none of the 65536 cases end up close to being between 2 32bit
> floats
> This would avoid teh rather complex code if it works

Can't test on other platform than x86_32 and x86_64, so i can't really
answer to this question.
It's the reason why, i write a code, which doesn't use float calc.


More information about the ffmpeg-devel mailing list