media/base/simd/convert_rgb_to_yuv_c.cc

   1 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "media/base/simd/convert_rgb_to_yuv.h"
   6
   7 namespace media {
   8
   9 static int clip_byte(int x) {
  10   if (x > 255)
  11     return 255;
  12   else if (x < 0)
  13     return 0;
  14   else
  15     return x;
  16 }
  17
  18 void ConvertRGB32ToYUV_C(const uint8* rgbframe,
  19                          uint8* yplane,
  20                          uint8* uplane,
  21                          uint8* vplane,
  22                          int width,
  23                          int height,
  24                          int rgbstride,
  25                          int ystride,
  26                          int uvstride) {
  27 #if defined(OS_ANDROID)
  28   const int r = 0;
  29   const int g = 1;
  30   const int b = 2;
  31 #else
  32   const int r = 2;
  33   const int g = 1;
  34   const int b = 0;
  35 #endif
  36
  37   for (int i = 0; i < height; ++i) {
  38     for (int j = 0; j < width; ++j) {
  39       // Since the input pixel format is RGB32, there are 4 bytes per pixel.
  40       const uint8* pixel = rgbframe + 4 * j;
  41       yplane[j] = clip_byte(((pixel[r] * 66 + pixel[g] * 129 +
  42                              pixel[b] * 25 + 128) >> 8) + 16);
  43       if (i % 2 == 0 && j % 2 == 0) {
  44         uplane[j / 2] = clip_byte(((pixel[r] * -38 + pixel[g] * -74 +
  45                                    pixel[b] * 112 + 128) >> 8) + 128);
  46         vplane[j / 2] = clip_byte(((pixel[r] * 112 + pixel[g] * -94 +
  47                                     pixel[b] * -18 + 128) >> 8) + 128);
  48       }
  49     }
  50     rgbframe += rgbstride;
  51     yplane += ystride;
  52     if (i % 2 == 0) {
  53       uplane += uvstride;
  54       vplane += uvstride;
  55     }
  56   }
  57 }
  58
  59 void ConvertRGB24ToYUV_C(const uint8* rgbframe,
  60                          uint8* yplane,
  61                          uint8* uplane,
  62                          uint8* vplane,
  63                          int width,
  64                          int height,
  65                          int rgbstride,
  66                          int ystride,
  67                          int uvstride) {
  68   for (int i = 0; i < height; ++i) {
  69     for (int j = 0; j < width; ++j) {
  70       // Since the input pixel format is RGB24, there are 3 bytes per pixel.
  71       const uint8* pixel = rgbframe + 3 * j;
  72       yplane[j] = clip_byte(((pixel[2] * 66 + pixel[1] * 129 +
  73                               pixel[0] * 25 + 128) >> 8) + 16);
  74       if (i % 2 == 0 && j % 2 == 0) {
  75         uplane[j / 2] = clip_byte(((pixel[2] * -38 + pixel[1] * -74 +
  76                                     pixel[0] * 112 + 128) >> 8) + 128);
  77         vplane[j / 2] = clip_byte(((pixel[2] * 112 + pixel[1] * -94 +
  78                                     pixel[0] * -18 + 128) >> 8) + 128);
  79       }
  80     }
  81
  82     rgbframe += rgbstride;
  83     yplane += ystride;
  84     if (i % 2 == 0) {
  85       uplane += uvstride;
  86       vplane += uvstride;
  87     }
  88   }
  89 }
  90
  91 }  // namespace media