libavcodec/colorspace.h

   1 /*
   2  * Colorspace conversion defines
   3  * Copyright (c) 2001, 2002, 2003 Fabrice Bellard.
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 /**
  23  * @file colorspace.h
  24  * Various defines for YUV<->RGB conversion
  25  */
  26
  27 #ifndef AVCODEC_COLORSPACE_H
  28 #define AVCODEC_COLORSPACE_H
  29
  30 #define SCALEBITS 10
  31 #define ONE_HALF  (1 << (SCALEBITS - 1))
  32 #define FIX(x)    ((int) ((x) * (1<<SCALEBITS) + 0.5))
  33
  34 #define YUV_TO_RGB1_CCIR(cb1, cr1)\
  35 {\
  36     cb = (cb1) - 128;\
  37     cr = (cr1) - 128;\
  38     r_add = FIX(1.40200*255.0/224.0) * cr + ONE_HALF;\
  39     g_add = - FIX(0.34414*255.0/224.0) * cb - FIX(0.71414*255.0/224.0) * cr + \
  40             ONE_HALF;\
  41     b_add = FIX(1.77200*255.0/224.0) * cb + ONE_HALF;\
  42 }
  43
  44 #define YUV_TO_RGB2_CCIR(r, g, b, y1)\
  45 {\
  46     y = ((y1) - 16) * FIX(255.0/219.0);\
  47     r = cm[(y + r_add) >> SCALEBITS];\
  48     g = cm[(y + g_add) >> SCALEBITS];\
  49     b = cm[(y + b_add) >> SCALEBITS];\
  50 }
  51
  52 #define YUV_TO_RGB1(cb1, cr1)\
  53 {\
  54     cb = (cb1) - 128;\
  55     cr = (cr1) - 128;\
  56     r_add = FIX(1.40200) * cr + ONE_HALF;\
  57     g_add = - FIX(0.34414) * cb - FIX(0.71414) * cr + ONE_HALF;\
  58     b_add = FIX(1.77200) * cb + ONE_HALF;\
  59 }
  60
  61 #define YUV_TO_RGB2(r, g, b, y1)\
  62 {\
  63     y = (y1) << SCALEBITS;\
  64     r = cm[(y + r_add) >> SCALEBITS];\
  65     g = cm[(y + g_add) >> SCALEBITS];\
  66     b = cm[(y + b_add) >> SCALEBITS];\
  67 }
  68
  69 #define Y_CCIR_TO_JPEG(y)\
  70  cm[((y) * FIX(255.0/219.0) + (ONE_HALF - 16 * FIX(255.0/219.0))) >> SCALEBITS]
  71
  72 #define Y_JPEG_TO_CCIR(y)\
  73  (((y) * FIX(219.0/255.0) + (ONE_HALF + (16 << SCALEBITS))) >> SCALEBITS)
  74
  75 #define C_CCIR_TO_JPEG(y)\
  76  cm[(((y) - 128) * FIX(127.0/112.0) + (ONE_HALF + (128 << SCALEBITS))) >> SCALEBITS]
  77
  78 /* NOTE: the clamp is really necessary! */
  79 static inline int C_JPEG_TO_CCIR(int y) {
  80     y = (((y - 128) * FIX(112.0/127.0) + (ONE_HALF + (128 << SCALEBITS))) >> SCALEBITS);
  81     if (y < 16)
  82         y = 16;
  83     return y;
  84 }
  85
  86
  87 #define RGB_TO_Y(r, g, b) \
  88 ((FIX(0.29900) * (r) + FIX(0.58700) * (g) + \
  89   FIX(0.11400) * (b) + ONE_HALF) >> SCALEBITS)
  90
  91 #define RGB_TO_U(r1, g1, b1, shift)\
  92 (((- FIX(0.16874) * r1 - FIX(0.33126) * g1 +         \
  93      FIX(0.50000) * b1 + (ONE_HALF << shift) - 1) >> (SCALEBITS + shift)) + 128)
  94
  95 #define RGB_TO_V(r1, g1, b1, shift)\
  96 (((FIX(0.50000) * r1 - FIX(0.41869) * g1 -           \
  97    FIX(0.08131) * b1 + (ONE_HALF << shift) - 1) >> (SCALEBITS + shift)) + 128)
  98
  99 #define RGB_TO_Y_CCIR(r, g, b) \
 100 ((FIX(0.29900*219.0/255.0) * (r) + FIX(0.58700*219.0/255.0) * (g) + \
 101   FIX(0.11400*219.0/255.0) * (b) + (ONE_HALF + (16 << SCALEBITS))) >> SCALEBITS)
 102
 103 #define RGB_TO_U_CCIR(r1, g1, b1, shift)\
 104 (((- FIX(0.16874*224.0/255.0) * r1 - FIX(0.33126*224.0/255.0) * g1 +         \
 105      FIX(0.50000*224.0/255.0) * b1 + (ONE_HALF << shift) - 1) >> (SCALEBITS + shift)) + 128)
 106
 107 #define RGB_TO_V_CCIR(r1, g1, b1, shift)\
 108 (((FIX(0.50000*224.0/255.0) * r1 - FIX(0.41869*224.0/255.0) * g1 -           \
 109    FIX(0.08131*224.0/255.0) * b1 + (ONE_HALF << shift) - 1) >> (SCALEBITS + shift)) + 128)
 110
 111 #endif /* AVCODEC_COLORSPACE_H */