Test color space against a reference function.

BUG=none
TESTED=TestYUV
R=tpsiaki@google.com

Review URL: https://webrtc-codereview.appspot.com/35789004

git-svn-id: http://libyuv.googlecode.com/svn/trunk@1229 16f28f9a-4ce2-e073-06de-1de4eb20be90

unit_test/color_test.cc

@@ -114,4 +114,77 @@ TESTCS(TestI422, I422ToARGB, ARGBToI422, 0, 1, 0, 7)
 TESTCS(TestJ420, J420ToARGB, ARGBToJ420, 1, 2, benchmark_width_, 3)
 TESTCS(TestJ422, J422ToARGB, ARGBToJ422, 0, 1, 0, 3)
 
+int Clamp(double f) {
+  int i = static_cast<int>(round(f));
+  if (i < 0) {
+    i = 0;
+  }
+  if (i > 255) {
+    i = 255;
+  }
+  return i;
+}
+
+void TestYUVToRGBReference(int y, int u, int v, int &r, int &g, int &b) {
+  r = Clamp((y - 16) * 1.164 + (v - 128) * 1.596);
+  g = Clamp((y - 16) * 1.164 + (u - 128) * -0.391 + (v - 128) * -0.813);
+  b = Clamp((y - 16) * 1.164 + (u - 128) * 2.018);
+}
+
+void TestYUVToRGB(int y, int u, int v, int &r, int &g, int &b,
+                  int benchmark_width_, int benchmark_height_) {
+  const int kPixels = benchmark_width_ * benchmark_height_;
+  const int kHalfPixels = ((benchmark_width_ + 1) / 2) *
+      ((benchmark_height_ + 1) / 2);
+  align_buffer_64(orig_y, kPixels);
+  align_buffer_64(orig_u, kHalfPixels);
+  align_buffer_64(orig_v, kHalfPixels);
+  align_buffer_64(orig_pixels, kPixels * 4);
+
+  memset(orig_y, y, kPixels);
+  memset(orig_u, u, kHalfPixels);
+  memset(orig_v, v, kHalfPixels);
+  MemRandomize(orig_pixels, kPixels * 4);
+
+  /* YUV converted to ARGB. */
+  I420ToARGB(orig_y, benchmark_width_,
+             orig_u, (benchmark_width_ + 1) / 2,
+             orig_v, (benchmark_width_ + 1) / 2,
+             orig_pixels, benchmark_width_ * 4,
+             benchmark_width_, benchmark_height_);
+
+  b = orig_pixels[0];
+  g = orig_pixels[1];
+  r = orig_pixels[2];
+
+  free_aligned_buffer_64(orig_pixels);
+  free_aligned_buffer_64(orig_y);
+  free_aligned_buffer_64(orig_u);
+  free_aligned_buffer_64(orig_v);
+}
+
+TEST_F(libyuvTest, TestYUV) {
+  int r0, g0, b0;
+  TestYUVToRGBReference(16, 128, 128, r0, g0, b0);
+  EXPECT_EQ(0, r0);
+  EXPECT_EQ(0, g0);
+  EXPECT_EQ(0, b0);
+
+  int r1, g1, b1;
+  TestYUVToRGB(16, 128, 128, r1, g1, b1, benchmark_width_, benchmark_height_);
+  EXPECT_EQ(0, r1);
+  EXPECT_EQ(0, g1);
+  EXPECT_EQ(0, b1);
+
+  TestYUVToRGBReference(240, 128, 128, r0, g0, b0);
+  EXPECT_EQ(255, r0);
+  EXPECT_EQ(255, g0);
+  EXPECT_EQ(255, b0);
+
+  TestYUVToRGB(240, 128, 128, r1, g1, b1, benchmark_width_, benchmark_height_);
+  EXPECT_EQ(255, r1);
+  EXPECT_EQ(254, g1);
+  EXPECT_EQ(255, b1);
+}
+
 }  // namespace libyuv