Dead code elimination: scythe.chrome_functions:segment.path %media% edition, round 1.

media/base/simd/convert_rgb_to_yuv_unittest.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/cpu.h"
 #include "base/memory/scoped_ptr.h"
 #include "media/base/simd/convert_rgb_to_yuv.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace {
 
 // Reference code that converts RGB pixels to YUV pixels.
 int ConvertRGBToY(const uint8* rgb) {
   int y = 25 * rgb[0] + 129 * rgb[1] + 66 * rgb[2];
   y = ((y + 128) >> 8) + 16;
   return std::max(0, std::min(255, y));
 }
 
-int ConvertRGBToU(const uint8* rgb, int size, bool subsampling) {
-  int u = 0;
-  if (!subsampling) {
-    u = 112 * rgb[0] - 74 * rgb[1] - 38 * rgb[2];
-  } else {
-    int u0 = 112 * rgb[0] - 74 * rgb[1] - 38 * rgb[2];
-    int u1 = 112 * rgb[size] - 74 * rgb[size + 1] - 38 * rgb[size + 2];
-    u = (u0 + u1 + 1) / 2;
-  }
+int ConvertRGBToU(const uint8* rgb, int size) {
+  int u = 112 * rgb[0] - 74 * rgb[1] - 38 * rgb[2];
   u = ((u + 128) >> 8) + 128;
   return std::max(0, std::min(255, u));
 }
 
-int ConvertRGBToV(const uint8* rgb, int size, bool subsampling) {
-  int v = 0;
-  if (!subsampling) {
-    v = -18 * rgb[0] - 94 * rgb[1] + 112 * rgb[2];
-  } else {
-    int v0 = -18 * rgb[0] - 94 * rgb[1] + 112 * rgb[2];
-    int v1 = -18 * rgb[size] - 94 * rgb[size + 1] + 112 * rgb[size + 2];
-    v = (v0 + v1 + 1) / 2;
-  }
+int ConvertRGBToV(const uint8* rgb, int size) {
+  int v = -18 * rgb[0] - 94 * rgb[1] + 112 * rgb[2];
   v = ((v + 128) >> 8) + 128;
   return std::max(0, std::min(255, v));
 }
 
 }  // namespace
 
 // A side-by-side test that verifies our ASM functions that convert RGB pixels
 // to YUV pixels can output the expected results. This test converts RGB pixels
 // to YUV pixels with our ASM functions (which use SSE, SSE2, SSE3, and SSSE3)
 // and compare the output YUV pixels with the ones calculated with out reference
 // functions implemented in C++.
 TEST(YUVConvertTest, SideBySideRGB) {
   // We skip this test on PCs which does not support SSE3 because this test
   // needs it.
   base::CPU cpu;
   if (!cpu.has_ssse3())
     return;
 
   // This test checks a subset of all RGB values so this test does not take so
   // long time.
   const int kStep = 8;
   const int kWidth = 256 / kStep;
 
-#ifdef ENABLE_SUBSAMPLING
-  const bool kSubsampling = true;
-#else
-  const bool kSubsampling = false;
-#endif
-
   for (int size = 3; size <= 4; ++size) {
     // Create the output buffers.
     scoped_array<uint8> rgb(new uint8[kWidth * size]);
     scoped_array<uint8> y(new uint8[kWidth]);
     scoped_array<uint8> u(new uint8[kWidth / 2]);
     scoped_array<uint8> v(new uint8[kWidth / 2]);
 
     // Choose the function that converts from RGB pixels to YUV ones.
     void (*convert)(const uint8*, uint8*, uint8*, uint8*,
                     int, int, int, int, int) = NULL;
@@ skipping 22 matching lines @@
         // Check the output Y pixels.
         for (int i = 0; i < kWidth; ++i) {
           const uint8* p = &rgb[i * size];
           int error = ConvertRGBToY(p) - y[i];
           total_error += error > 0 ? error : -error;
         }
 
         // Check the output U pixels.
         for (int i = 0; i < kWidth / 2; ++i) {
           const uint8* p = &rgb[i * 2 * size];
-          int error = ConvertRGBToU(p, size, kSubsampling) - u[i];
+          int error = ConvertRGBToU(p, size) - u[i];
           total_error += error > 0 ? error : -error;
         }
 
         // Check the output V pixels.
         for (int i = 0; i < kWidth / 2; ++i) {
           const uint8* p = &rgb[i * 2 * size];
-          int error = ConvertRGBToV(p, size, kSubsampling) - v[i];
+          int error = ConvertRGBToV(p, size) - v[i];
           total_error += error > 0 ? error : -error;
         }
       }
     }
 
     EXPECT_EQ(0, total_error);
   }
 }