From 3bef1dab6e881bf593037f831e66ed87c6167e3c Mon Sep 17 00:00:00 2001 From: Gyan Doshi Date: Sat, 13 Apr 2019 17:01:09 +0530 Subject: [PATCH] avutil/colorspace: add macros for RGB->YUV BT.709 --- libavutil/colorspace.h | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/libavutil/colorspace.h b/libavutil/colorspace.h index d0be8cb99a..ef6f6107d6 100644 --- a/libavutil/colorspace.h +++ b/libavutil/colorspace.h @@ -119,4 +119,32 @@ static inline int C_JPEG_TO_CCIR(int y) { (((FIX(0.50000) * r1 - FIX(0.41869) * g1 - \ FIX(0.08131) * b1 + (ONE_HALF) - 1) >> (SCALEBITS)) + 128) +// Conversion macros for 8-bit RGB to YUV +// Derived from ITU-R BT.709-6 (06/2015) Item 3.5 +// https://www.itu.int/rec/R-REC-BT.709-6-201506-I/en + +#define RGB_TO_Y_BT709(r, g, b) \ +((FIX(0.21260*219.0/255.0) * (r) + FIX(0.71520*219.0/255.0) * (g) + \ + FIX(0.07220*219.0/255.0) * (b) + (ONE_HALF + (16 << SCALEBITS))) >> SCALEBITS) + +#define RGB_TO_U_BT709(r1, g1, b1, shift)\ +(((- FIX(0.11457*224.0/255.0) * r1 - FIX(0.38543*224.0/255.0) * g1 + \ + FIX(0.50000*224.0/255.0) * b1 + (ONE_HALF << shift) - 1) >> (SCALEBITS + shift)) + 128) + +#define RGB_TO_V_BT709(r1, g1, b1, shift)\ +(((FIX(0.50000*224.0/255.0) * r1 - FIX(0.45415*224.0/255.0) * g1 - \ + FIX(0.04585*224.0/255.0) * b1 + (ONE_HALF << shift) - 1) >> (SCALEBITS + shift)) + 128) + +#define RGB_TO_Y_BT709_FULL(r, g, b) \ +(FFMIN((FIX(0.21260) * (r) + FIX(0.71520) * (g) + \ + FIX(0.07220) * (b) + (ONE_HALF)) >> SCALEBITS, 255)) + +#define RGB_TO_U_BT709_FULL(r1, g1, b1)\ +(((- FIX(0.11457) * r1 - FIX(0.38543) * g1 + \ + FIX(0.50000) * b1 + (ONE_HALF) - 1) >> (SCALEBITS)) + 128) + +#define RGB_TO_V_BT709_FULL(r1, g1, b1)\ +(((FIX(0.50000) * r1 - FIX(0.45415) * g1 - \ + FIX(0.04585) * b1 + (ONE_HALF) - 1) >> (SCALEBITS)) + 128) + #endif /* AVUTIL_COLORSPACE_H */