media/cast/test/video_utility.cc

   1 // Copyright 2013 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 <math.h>
   6
   7 #include "media/cast/test/video_utility.h"
   8
   9 namespace media {
  10 namespace cast {
  11
  12 double I420PSNR(const I420VideoFrame& frame1, const I420VideoFrame& frame2) {
  13   // Frames should have equal resolution.
  14   if (frame1.width != frame2.width || frame1.height != frame2.height) return -1;
  15
  16   double y_mse = 0.0;
  17   // Y.
  18   uint8* data1 = frame1.y_plane.data;
  19   uint8* data2 = frame2.y_plane.data;
  20   for (int i = 0; i < frame1.height; ++i) {
  21     for (int j = 0; j < frame1.width; ++j) {
  22       y_mse += (data1[j] - data2[j]) * (data1[j] - data2[j]);
  23     }
  24     // Account for stride.
  25     data1 += frame1.y_plane.stride;
  26     data2 += frame2.y_plane.stride;
  27   }
  28   y_mse /= (frame1.width * frame1.height);
  29
  30   int half_width = (frame1.width + 1) / 2;
  31   int half_height = (frame1.height + 1) / 2;
  32   // U.
  33   double u_mse = 0.0;
  34   data1 = frame1.u_plane.data;
  35   data2 = frame2.u_plane.data;
  36   for (int i = 0; i < half_height; ++i) {
  37     for (int j = 0; j < half_width; ++j) {
  38       u_mse += (data1[j] - data2[j]) * (data1[j] - data2[j]);
  39     }
  40     // Account for stride.
  41     data1 += frame1.u_plane.stride;
  42     data2 += frame2.u_plane.stride;
  43   }
  44   u_mse /= half_width * half_height;
  45
  46   // V.
  47   double v_mse = 0.0;
  48   data1 = frame1.v_plane.data;
  49   data2 = frame2.v_plane.data;
  50   for (int i = 0; i < half_height; ++i) {
  51     for (int j = 0; j < half_width; ++j) {
  52       v_mse += (data1[j] - data2[j]) * (data1[j] - data2[j]);
  53     }
  54     // Account for stride.
  55     data1 += frame1.v_plane.stride;
  56     data2 += frame2.v_plane.stride;
  57   }
  58   v_mse /= half_width * half_height;
  59
  60   // Combine to one psnr value.
  61   static const double kVideoBitRange = 255.0;
  62   return 20.0 * log10(kVideoBitRange) -
  63       10.0 * log10((y_mse + u_mse + v_mse) / 3.0);
  64 }
  65
  66 void PopulateVideoFrame(I420VideoFrame* frame, int start_value) {
  67   int half_width = (frame->width + 1) / 2;
  68   int half_height = (frame->height + 1) / 2;
  69   frame->y_plane.stride = frame->width;
  70   frame->y_plane.length = frame->width * frame->height;
  71   frame->y_plane.data = new uint8[frame->y_plane.length];
  72
  73   frame->u_plane.stride = half_width;
  74   frame->u_plane.length = half_width * half_height;
  75   frame->u_plane.data = new uint8[frame->u_plane.length];
  76
  77   frame->v_plane.stride = half_width;
  78   frame->v_plane.length = half_width * half_height;
  79   frame->v_plane.data = new uint8[frame->v_plane.length];
  80
  81   // Set Y.
  82   for (int i = 0; i < frame->y_plane.length; ++i) {
  83     frame->y_plane.data[i] = static_cast<uint8>(start_value + i);
  84   }
  85
  86   // Set U.
  87   for (int i = 0; i < frame->u_plane.length; ++i) {
  88     frame->u_plane.data[i] = static_cast<uint8>(start_value + i);
  89   }
  90
  91   // Set V.
  92   for (int i = 0; i < frame->v_plane.length; ++i) {
  93     frame->v_plane.data[i] = static_cast<uint8>(start_value + i);
  94   }
  95 }
  96
  97 }  // namespace cast
  98 }  // namespace media