Add a unit test for 4:2:0 YCbCr input.
authorSteinar H. Gunderson <sgunderson@bigfoot.com>
Mon, 15 Oct 2012 18:04:42 +0000 (20:04 +0200)
committerSteinar H. Gunderson <sgunderson@bigfoot.com>
Mon, 15 Oct 2012 18:04:42 +0000 (20:04 +0200)
ycbcr_input_test.cpp

index 53b8289..70cbc12 100644 (file)
@@ -107,3 +107,121 @@ TEST(YCbCrInput, FullRangeRec601) {
        // so we need some leeway.
        expect_equal(expected_data, out_data, 4 * width, height, 0.025, 0.002);
 }
+
+TEST(YCbCrInput, Subsampling420) {
+       const int width = 4;
+       const int height = 4;
+
+       unsigned char y[width * height] = {
+               126, 126, 126, 126,
+               126, 126, 126, 126,
+               126, 126, 126, 126,
+               126, 126, 126, 126,
+       };
+       unsigned char cb[(width/2) * (height/2)] = {
+               64, 128,
+               128, 192,
+       };
+       unsigned char cr[(width/2) * (height/2)] = {
+               128, 128,
+               128, 128,
+       };
+
+       // Note: This is only the blue channel. The chroma samples (with associated
+       // values for blue) are marked off in comments.
+       float expected_data[width * height] = {
+               0.000, 0.125, 0.375, 0.500, 
+                /* 0.0 */      /* 0.5 */
+               0.125, 0.250, 0.500, 0.625,
+
+               0.375, 0.500, 0.750, 0.875,
+                /* 0.5 */      /* 1.0 */
+               0.500, 0.625, 0.875, 1.000,
+       };
+       float out_data[width * height];
+
+       EffectChainTester tester(NULL, width, height);
+
+       ImageFormat format;
+       format.color_space = COLORSPACE_sRGB;
+       format.gamma_curve = GAMMA_sRGB;
+
+       YCbCrFormat ycbcr_format;
+       ycbcr_format.luma_coefficients = YCBCR_REC_601;
+       ycbcr_format.full_range = false;
+       ycbcr_format.chroma_subsampling_x = 2;
+       ycbcr_format.chroma_subsampling_y = 2;
+       ycbcr_format.chroma_x_position = 0.5f;
+       ycbcr_format.chroma_y_position = 0.5f;
+
+       YCbCrInput *input = new YCbCrInput(format, ycbcr_format, width, height);
+       input->set_pixel_data(0, y);
+       input->set_pixel_data(1, cb);
+       input->set_pixel_data(2, cr);
+       tester.get_chain()->add_input(input);
+
+       tester.run(out_data, GL_BLUE, COLORSPACE_sRGB, GAMMA_sRGB);
+
+       // Y'CbCr isn't 100% accurate (the input values are rounded),
+       // so we need some leeway.
+       expect_equal(expected_data, out_data, width, height, 0.01, 0.001);
+}
+
+TEST(YCbCrInput, Subsampling420WithNonCenteredSamples) {
+       const int width = 4;
+       const int height = 4;
+
+       unsigned char y[width * height] = {
+               126, 126, 126, 126,
+               126, 126, 126, 126,
+               126, 126, 126, 126,
+               126, 126, 126, 126,
+       };
+       unsigned char cb[(width/2) * (height/2)] = {
+               64, 128,
+               128, 192,
+       };
+       unsigned char cr[(width/2) * (height/2)] = {
+               128, 128,
+               128, 128,
+       };
+
+       // Note: This is only the blue channel. The chroma samples (with associated
+       // values for blue) are marked off in comments.
+       float expected_data[width * height] = {
+                  0.000, 0.250, 0.500, 0.500, 
+               /* 0.0 */     /* 0.5 */
+                  0.125, 0.375, 0.625, 0.625,
+
+                  0.375, 0.625, 0.875, 0.875,
+               /* 0.5 */     /* 1.0 */
+                  0.500, 0.750, 1.000, 1.000,
+       };
+       float out_data[width * height];
+
+       EffectChainTester tester(NULL, width, height);
+
+       ImageFormat format;
+       format.color_space = COLORSPACE_sRGB;
+       format.gamma_curve = GAMMA_sRGB;
+
+       YCbCrFormat ycbcr_format;
+       ycbcr_format.luma_coefficients = YCBCR_REC_601;
+       ycbcr_format.full_range = false;
+       ycbcr_format.chroma_subsampling_x = 2;
+       ycbcr_format.chroma_subsampling_y = 2;
+       ycbcr_format.chroma_x_position = 0.0f;
+       ycbcr_format.chroma_y_position = 0.5f;
+
+       YCbCrInput *input = new YCbCrInput(format, ycbcr_format, width, height);
+       input->set_pixel_data(0, y);
+       input->set_pixel_data(1, cb);
+       input->set_pixel_data(2, cr);
+       tester.get_chain()->add_input(input);
+
+       tester.run(out_data, GL_BLUE, COLORSPACE_sRGB, GAMMA_sRGB);
+
+       // Y'CbCr isn't 100% accurate (the input values are rounded),
+       // so we need some leeway.
+       expect_equal(expected_data, out_data, width, height, 0.01, 0.001);
+}