From: Steinar H. Gunderson <sgunderson@bigfoot.com>
Date: Mon, 15 Oct 2012 18:04:42 +0000 (+0200)
Subject: Add a unit test for 4:2:0 YCbCr input.
X-Git-Tag: 1.0~231
X-Git-Url: https://git.sesse.net/?p=movit;a=commitdiff_plain;h=6f0ec2d7c127b139ed7cc42348bf518236e12dbd

Add a unit test for 4:2:0 YCbCr input.
---

diff --git a/ycbcr_input_test.cpp b/ycbcr_input_test.cpp
index 53b8289..70cbc12 100644
--- a/ycbcr_input_test.cpp
+++ b/ycbcr_input_test.cpp
@@ -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);
+}