X-Git-Url: https://git.sesse.net/?p=movit;a=blobdiff_plain;f=resample_effect_test.cpp;h=02d9d74d1102ace6a956331bac2280f8a368060f;hp=95c2bcfb9aec95693653ea65572cfdca76f79699;hb=34776d3ed2565ee834405e575bf3bfc7f7933e36;hpb=c5b9c3df43caa7a88f2f729a5c52359ca8ca537f

diff --git a/resample_effect_test.cpp b/resample_effect_test.cpp
index 95c2bcf..02d9d74 100644
--- a/resample_effect_test.cpp
+++ b/resample_effect_test.cpp
@@ -96,11 +96,11 @@ TEST(ResampleEffectTest, DownscaleByTwoGetsCorrectPixelCenters) {
 	// the texel center right (everything is nicely symmetric).
 	// The approximate magnitudes have been checked against ImageMagick.
 	float expected_data[size * size] = {
-		 0.0045, -0.0067, -0.0598, -0.0067,  0.0045, 
-		-0.0067,  0.0099,  0.0886,  0.0099, -0.0067, 
-		-0.0598,  0.0886,  0.7930,  0.0886, -0.0598, 
-		-0.0067,  0.0099,  0.0886,  0.0099, -0.0067, 
-		 0.0045, -0.0067, -0.0598, -0.0067,  0.0045, 
+		 0.0045, -0.0067, -0.0599, -0.0067,  0.0045,
+		-0.0067,  0.0100,  0.0892,  0.0100, -0.0067,
+		-0.0599,  0.0890,  0.7925,  0.0892, -0.0599,
+		-0.0067,  0.0100,  0.0890,  0.0100, -0.0067,
+		 0.0045, -0.0067, -0.0599, -0.0067,  0.0045,
 	};
 	float data[size * size * 4], out_data[size * size];
 
@@ -162,8 +162,8 @@ TEST(ResampleEffectTest, UpscaleByThreeGetsCorrectPixelCenters) {
 	EXPECT_FLOAT_EQ(1.0, out_data[7 * (size * 3) + 7]);
 	for (unsigned y = 0; y < size * 3; ++y) {
 		for (unsigned x = 0; x < size * 3; ++x) {
-			EXPECT_FLOAT_EQ(out_data[y * (size * 3) + x], out_data[(size * 3 - y - 1) * (size * 3) + x]);
-			EXPECT_FLOAT_EQ(out_data[y * (size * 3) + x], out_data[y * (size * 3) + (size * 3 - x - 1)]);
+			EXPECT_NEAR(out_data[y * (size * 3) + x], out_data[(size * 3 - y - 1) * (size * 3) + x], 1e-6);
+			EXPECT_NEAR(out_data[y * (size * 3) + x], out_data[y * (size * 3) + (size * 3 - x - 1)], 1e-6);
 		}
 	}
 }
@@ -205,7 +205,224 @@ TEST(ResampleEffectTest, HeavyResampleGetsSumRight) {
 	// Require that we are within 10-bit accuracy. Note that this limit is for
 	// one pass only, but the limit is tight enough that it should be good enough
 	// for 10-bit accuracy even after two passes.
-	expect_equal(expected_data, out_data, dwidth, dheight, 0.1 / 1023.0);
+	expect_equal(expected_data, out_data, dwidth, dheight, 0.12 / 1023.0);
+}
+
+TEST(ResampleEffectTest, ReadWholePixelFromLeft) {
+	const int size = 5;
+
+	float data[size * size] = {
+		0.0, 0.0, 0.0, 0.0, 0.0,
+		0.0, 0.0, 0.0, 0.0, 0.0,
+		0.0, 0.0, 1.0, 0.0, 0.0,
+		0.0, 0.0, 0.0, 0.0, 0.0,
+		0.0, 0.0, 0.0, 0.0, 0.0,
+	};
+	float expected_data[size * size] = {
+		0.0, 0.0, 0.0, 0.0, 0.0,
+		0.0, 0.0, 0.0, 0.0, 0.0,
+		0.0, 1.0, 0.0, 0.0, 0.0,
+		0.0, 0.0, 0.0, 0.0, 0.0,
+		0.0, 0.0, 0.0, 0.0, 0.0,
+	};
+	float out_data[size * size];
+
+	EffectChainTester tester(data, size, size, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_LINEAR);
+	Effect *resample_effect = tester.get_chain()->add_effect(new ResampleEffect());
+	ASSERT_TRUE(resample_effect->set_int("width", size));
+	ASSERT_TRUE(resample_effect->set_int("height", size));
+	ASSERT_TRUE(resample_effect->set_float("left", 1.0f));
+	tester.run(out_data, GL_RED, COLORSPACE_sRGB, GAMMA_LINEAR);
+
+	expect_equal(expected_data, out_data, size, size);
+}
+
+TEST(ResampleEffectTest, ReadQuarterPixelFromLeft) {
+	const int size = 5;
+
+	float data[size * size] = {
+		0.0, 0.0, 0.0, 0.0, 0.0,
+		0.0, 0.0, 0.0, 0.0, 0.0,
+		0.0, 0.0, 1.0, 0.0, 0.0,
+		0.0, 0.0, 0.0, 0.0, 0.0,
+		0.0, 0.0, 0.0, 0.0, 0.0,
+	};
+
+	float expected_data[size * size] = {
+		0.0, 0.0, 0.0, 0.0, 0.0,
+		0.0, 0.0, 0.0, 0.0, 0.0,
+
+		// sin(x*pi)/(x*pi) * sin(x*pi/3)/(x*pi/3) for
+		// x = -1.75, -0.75, 0.25, 1.25, 2.25.
+		// Note that the weight is mostly on the left side.
+		-0.06779, 0.27019, 0.89007, -0.13287, 0.03002,
+
+		0.0, 0.0, 0.0, 0.0, 0.0,
+		0.0, 0.0, 0.0, 0.0, 0.0,
+	};
+	float out_data[size * size];
+
+	EffectChainTester tester(data, size, size, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_LINEAR);
+	Effect *resample_effect = tester.get_chain()->add_effect(new ResampleEffect());
+	ASSERT_TRUE(resample_effect->set_int("width", size));
+	ASSERT_TRUE(resample_effect->set_int("height", size));
+	ASSERT_TRUE(resample_effect->set_float("left", 0.25f));
+	tester.run(out_data, GL_RED, COLORSPACE_sRGB, GAMMA_LINEAR);
+
+	expect_equal(expected_data, out_data, size, size);
+}
+
+TEST(ResampleEffectTest, ReadQuarterPixelFromTop) {
+	const int width = 3;
+	const int height = 5;
+
+	float data[width * height] = {
+		0.0, 0.0, 0.0,
+		0.0, 0.0, 0.0,
+		1.0, 0.0, 0.0,
+		0.0, 0.0, 0.0,
+		0.0, 0.0, 0.0,
+	};
+
+	// See ReadQuarterPixelFromLeft for explanation of the data.
+	float expected_data[width * height] = {
+		-0.06779, 0.0, 0.0,
+		 0.27019, 0.0, 0.0,
+		 0.89007, 0.0, 0.0,
+		-0.13287, 0.0, 0.0,
+		 0.03002, 0.0, 0.0,
+	};
+	float out_data[width * height];
+
+	EffectChainTester tester(data, width, height, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_LINEAR);
+	Effect *resample_effect = tester.get_chain()->add_effect(new ResampleEffect());
+	ASSERT_TRUE(resample_effect->set_int("width", width));
+	ASSERT_TRUE(resample_effect->set_int("height", height));
+	ASSERT_TRUE(resample_effect->set_float("top", 0.25f));
+	tester.run(out_data, GL_RED, COLORSPACE_sRGB, GAMMA_LINEAR);
+
+	expect_equal(expected_data, out_data, width, height);
+}
+
+TEST(ResampleEffectTest, ReadHalfPixelFromLeftAndScale) {
+	const int src_width = 4;
+	const int dst_width = 8;
+
+	float data[src_width * 1] = {
+		1.0, 2.0, 3.0, 4.0,
+	};
+	float expected_data[dst_width * 1] = {
+		// Empirical; the real test is that we are the same for 0.499 and 0.501.
+		1.1553, 1.7158, 2.2500, 2.7461, 3.2812, 3.8418, 4.0703, 4.0508
+	};
+	float out_data[dst_width * 1];
+
+	EffectChainTester tester(NULL, dst_width, 1, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_LINEAR);
+
+	ImageFormat format;
+	format.color_space = COLORSPACE_sRGB;
+	format.gamma_curve = GAMMA_LINEAR;
+
+	FlatInput *input = new FlatInput(format, FORMAT_GRAYSCALE, GL_FLOAT, src_width, 1);
+	input->set_pixel_data(data);
+	tester.get_chain()->add_input(input);
+
+	Effect *resample_effect = tester.get_chain()->add_effect(new ResampleEffect());
+	ASSERT_TRUE(resample_effect->set_int("width", dst_width));
+	ASSERT_TRUE(resample_effect->set_int("height", 1));
+
+	// Check that we are (almost) the same no matter the rounding.
+	ASSERT_TRUE(resample_effect->set_float("left", 0.499f));
+	tester.run(out_data, GL_RED, COLORSPACE_sRGB, GAMMA_LINEAR);
+	expect_equal(expected_data, out_data, dst_width, 1, 1.5f / 255.0f, 0.4f / 255.0f);
+
+	ASSERT_TRUE(resample_effect->set_float("left", 0.501f));
+	tester.run(out_data, GL_RED, COLORSPACE_sRGB, GAMMA_LINEAR);
+	expect_equal(expected_data, out_data, dst_width, 1, 1.5f / 255.0f, 0.4f / 255.0f);
+}
+
+TEST(ResampleEffectTest, Zoom) {
+	const int width = 5;
+	const int height = 3;
+
+	float data[width * height] = {
+		0.0, 0.0, 0.0, 0.0, 0.0,
+		0.2, 0.4, 0.6, 0.4, 0.2,
+		0.0, 0.0, 0.0, 0.0, 0.0,
+	};
+	float expected_data[width * height] = {
+		0.0, 0.0,    0.0, 0.0,    0.0,
+		0.4, 0.5396, 0.6, 0.5396, 0.4,
+		0.0, 0.0,    0.0, 0.0,    0.0,
+	};
+	float out_data[width * height];
+
+	EffectChainTester tester(data, width, height, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_LINEAR);
+	Effect *resample_effect = tester.get_chain()->add_effect(new ResampleEffect());
+	ASSERT_TRUE(resample_effect->set_int("width", width));
+	ASSERT_TRUE(resample_effect->set_int("height", height));
+	ASSERT_TRUE(resample_effect->set_float("zoom_x", 2.0f));
+	tester.run(out_data, GL_RED, COLORSPACE_sRGB, GAMMA_LINEAR);
+
+	expect_equal(expected_data, out_data, width, height);
+}
+
+TEST(ResampleEffectTest, VerticalZoomFromTop) {
+	const int width = 5;
+	const int height = 5;
+
+	float data[width * height] = {
+		0.2, 0.4, 0.6, 0.4, 0.2,
+		0.0, 0.0, 0.0, 0.0, 0.0,
+		0.0, 0.0, 0.0, 0.0, 0.0,
+		0.0, 0.0, 0.0, 0.0, 0.0,
+		0.0, 0.0, 0.0, 0.0, 0.0,
+	};
+
+	// Largely empirical data; the main point is that the top line
+	// is unchanged, since that's our zooming point.
+	float expected_data[width * height] = {
+		 0.2000,  0.4000,  0.6000,  0.4000,  0.2000,
+		 0.1389,  0.2778,  0.4167,  0.2778,  0.1389,
+		 0.0600,  0.1199,  0.1798,  0.1199,  0.0600,
+		 0.0000,  0.0000,  0.0000,  0.0000,  0.0000,
+		-0.0229, -0.0459, -0.0688, -0.0459, -0.0229,
+	};
+	float out_data[width * height];
+
+	EffectChainTester tester(data, width, height, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_LINEAR);
+	Effect *resample_effect = tester.get_chain()->add_effect(new ResampleEffect());
+	ASSERT_TRUE(resample_effect->set_int("width", width));
+	ASSERT_TRUE(resample_effect->set_int("height", height));
+	ASSERT_TRUE(resample_effect->set_float("zoom_y", 3.0f));
+	ASSERT_TRUE(resample_effect->set_float("zoom_center_y", 0.5f / height));
+	tester.run(out_data, GL_RED, COLORSPACE_sRGB, GAMMA_LINEAR);
+
+	expect_equal(expected_data, out_data, width, height);
+}
+
+TEST(ResampleEffectTest, Precision) {
+	const int size = 1920;  // Difficult non-power-of-two size.
+	const int offset = 5;
+
+	// Deliberately put the data of interest very close to the right,
+	// where texture coordinates are farther from 0 and thus less precise.
+	float data[size * 2] = {0};
+	data[size - offset] = 1.0f;
+	float expected_data[size * 2] = {0};
+	for (int x = 0; x < size * 2; ++x) {
+		expected_data[x] = lanczos((x - (size - 2 * offset + 1) + 0.5f) * 0.5f, 3.0f);
+	}
+	float out_data[size * 2];
+
+	EffectChainTester tester(data, size * 2, 1, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_LINEAR);
+	Effect *resample_effect = tester.get_chain()->add_effect(new ResampleEffect());
+	ASSERT_TRUE(resample_effect->set_int("width", size * 2));
+	ASSERT_TRUE(resample_effect->set_int("height", 1));
+	ASSERT_TRUE(resample_effect->set_float("zoom_x", 2.0f));
+	tester.run(out_data, GL_RED, COLORSPACE_sRGB, GAMMA_LINEAR);
+
+	expect_equal(expected_data, out_data, size, 1);
 }
 
 }  // namespace movit