Merge "Several fixes to recovery map math." (e6d0e201) · Commits · e / os / platform_frameworks_native

libs/jpegrecoverymap/include/jpegrecoverymap/recoverymapmath.h

+133 −13

Original line number	Diff line number	Diff line
		@@ -23,6 +23,9 @@

		namespace android::recoverymap {

		////////////////////////////////////////////////////////////////////////////////
		// Framework

		const float kSdrWhiteNits = 100.0f;

		struct Color {
		@@ -40,34 +43,141 @@ struct Color {
		};
		};

		inline Color operator+=(Color& lhs, const Color& rhs) {
		lhs.r += rhs.r;
		lhs.g += rhs.g;
		lhs.b += rhs.b;
		return lhs;
		}
		inline Color operator-=(Color& lhs, const Color& rhs) {
		lhs.r -= rhs.r;
		lhs.g -= rhs.g;
		lhs.b -= rhs.b;
		return lhs;
		}

		inline Color operator+(const Color& lhs, const Color& rhs) {
		Color temp = lhs;
		return temp += rhs;
		}
		inline Color operator-(const Color& lhs, const Color& rhs) {
		Color temp = lhs;
		return temp -= rhs;
		}

		inline Color operator+=(Color& lhs, const float rhs) {
		lhs.r += rhs;
		lhs.g += rhs;
		lhs.b += rhs;
		return lhs;
		}
		inline Color operator-=(Color& lhs, const float rhs) {
		lhs.r -= rhs;
		lhs.g -= rhs;
		lhs.b -= rhs;
		return lhs;
		}
		inline Color operator*=(Color& lhs, const float rhs) {
		lhs.r *= rhs;
		lhs.g *= rhs;
		lhs.b *= rhs;
		return lhs;
		}
		inline Color operator/=(Color& lhs, const float rhs) {
		lhs.r /= rhs;
		lhs.g /= rhs;
		lhs.b /= rhs;
		return lhs;
		}

		inline Color operator+(const Color& lhs, const float rhs) {
		Color temp = lhs;
		return temp += rhs;
		}
		inline Color operator-(const Color& lhs, const float rhs) {
		Color temp = lhs;
		return temp -= rhs;
		}
		inline Color operator*(const Color& lhs, const float rhs) {
		Color temp = lhs;
		return temp *= rhs;
		}
		inline Color operator/(const Color& lhs, const float rhs) {
		Color temp = lhs;
		return temp /= rhs;
		}


		////////////////////////////////////////////////////////////////////////////////
		// sRGB transformations

		/*
		* Calculate the luminance of a linear RGB sRGB pixel, according to IEC 61966-2-1.
		*/
		float srgbLuminance(Color e);

		/*
		* Convert from OETF'd bt.2100 RGB to YUV, according to BT.2100
		* Convert from OETF'd srgb YUV to RGB, according to ECMA TR/98.
		*/
		Color bt2100RgbToYuv(Color e);
		Color srgbYuvToRgb(Color e_gamma);

		/*
		* Convert srgb YUV to RGB, according to ECMA TR/98.
		* Convert from OETF'd srgb RGB to YUV, according to ECMA TR/98.
		*/
		Color srgbYuvToRgb(Color e);
		Color srgbRgbToYuv(Color e_gamma);

		/*
		* TODO: better source for srgb transfer function
		* Convert from srgb to linear, according to https://en.wikipedia.org/wiki/SRGB.
		* Convert from srgb to linear, according to IEC 61966-2-1.
		*
		* [0.0, 1.0] range in and out.
		*/
		float srgbInvOetf(float e);
		Color srgbInvOetf(Color e);
		float srgbInvOetf(float e_gamma);
		Color srgbInvOetf(Color e_gamma);


		////////////////////////////////////////////////////////////////////////////////
		// Display-P3 transformations




		////////////////////////////////////////////////////////////////////////////////
		// BT.2100 transformations - according to ITU-R BT.2100-2

		/*
		* Calculate the luminance of a linear RGB BT.2100 pixel.
		*/
		float bt2100Luminance(Color e);

		/*
		* Convert from OETF'd BT.2100 RGB to YUV.
		*/
		Color bt2100RgbToYuv(Color e_gamma);

		/*
		* Convert from HLG to scene luminance in nits, according to BT.2100.
		* Convert from OETF'd BT.2100 YUV to RGB.
		*/
		float hlgInvOetf(float e);
		Color bt2100YuvToRgb(Color e_gamma);

		/*
		* Convert from scene luminance in nits to HLG, according to BT.2100.
		* Convert from scene luminance in nits to HLG.
		*/
		Color hlgOetf(Color e);

		/*
		* Convert from HLG to scene luminance in nits.
		*/
		Color hlgInvOetf(Color e_gamma);

		////////////////////////////////////////////////////////////////////////////////
		// Color space conversions




		////////////////////////////////////////////////////////////////////////////////
		// Recovery map calculations

		/*
		* Calculate the 8-bit unsigned integer recovery value for the given SDR and HDR
		* luminances in linear space, and the hdr ratio to encode against.
		@@ -85,6 +195,11 @@ Color applyRecovery(Color e, float recovery, float hdr_ratio);
		*/
		Color getYuv420Pixel(jr_uncompressed_ptr image, size_t x, size_t y);

		/*
		* Helper for sampling from images.
		*/
		Color getP010Pixel(jr_uncompressed_ptr image, size_t x, size_t y);

		/*
		* Sample the recovery value for the map from a given x,y coordinate on a scale
		* that is map scale factor larger than the map size.
		@@ -97,8 +212,13 @@ float sampleMap(jr_uncompressed_ptr map, size_t map_scale_factor, size_t x, size
		*
		* Expect narrow-range image data for P010.
		*/
		float sampleYuv420Y(jr_uncompressed_ptr map, size_t map_scale_factor, size_t x, size_t y);
		float sampleP010Y(jr_uncompressed_ptr map, size_t map_scale_factor, size_t x, size_t y);
		Color sampleYuv420(jr_uncompressed_ptr map, size_t map_scale_factor, size_t x, size_t y);

		/*
		* Sample the image Y value at the provided location, with a weighting based on nearby pixels
		* and the map scale factor. Assumes narrow-range image data for P010.
		*/
		Color sampleP010(jr_uncompressed_ptr map, size_t map_scale_factor, size_t x, size_t y);

		} // namespace android::recoverymap

libs/jpegrecoverymap/recoverymap.cpp

+21 −13

Original line number	Diff line number	Diff line
		@@ -301,31 +301,38 @@ status_t RecoveryMap::generateRecoveryMap(jr_uncompressed_ptr uncompressed_yuv_4
		std::unique_ptr<uint8_t[]> map_data;
		map_data.reset(reinterpret_cast<uint8_t*>(dest->data));

		uint16_t yp_hdr_max = 0;
		float hdr_y_nits_max = 0.0f;
		for (size_t y = 0; y < image_height; ++y) {
		for (size_t x = 0; x < image_width; ++x) {
		size_t pixel_idx = x + y * image_width;
		uint16_t yp_hdr = reinterpret_cast<uint8_t*>(uncompressed_yuv_420_image->data)[pixel_idx];
		if (yp_hdr > yp_hdr_max) {
		yp_hdr_max = yp_hdr;
		Color hdr_yuv_gamma = getP010Pixel(uncompressed_p010_image, x, y);
		Color hdr_rgb_gamma = bt2100YuvToRgb(hdr_yuv_gamma);
		Color hdr_rgb = hlgInvOetf(hdr_rgb_gamma);
		float hdr_y_nits = bt2100Luminance(hdr_rgb);

		if (hdr_y_nits > hdr_y_nits_max) {
		hdr_y_nits_max = hdr_y_nits;
		}
		}
		}

		float y_hdr_max_nits = hlgInvOetf(yp_hdr_max);
		hdr_ratio = y_hdr_max_nits / kSdrWhiteNits;
		hdr_ratio = hdr_y_nits_max / kSdrWhiteNits;

		for (size_t y = 0; y < map_height; ++y) {
		for (size_t x = 0; x < map_width; ++x) {
		float yp_sdr = sampleYuv420Y(uncompressed_yuv_420_image, kMapDimensionScaleFactor, x, y);
		float yp_hdr = sampleP010Y(uncompressed_p010_image, kMapDimensionScaleFactor, x, y);
		Color sdr_yuv_gamma = sampleYuv420(uncompressed_yuv_420_image,
		kMapDimensionScaleFactor, x, y);
		Color sdr_rgb_gamma = srgbYuvToRgb(sdr_yuv_gamma);
		Color sdr_rgb = srgbInvOetf(sdr_rgb_gamma);
		float sdr_y_nits = srgbLuminance(sdr_rgb);

		float y_sdr_nits = srgbInvOetf(yp_sdr);
		float y_hdr_nits = hlgInvOetf(yp_hdr);
		Color hdr_yuv_gamma = sampleP010(uncompressed_p010_image, kMapDimensionScaleFactor, x, y);
		Color hdr_rgb_gamma = bt2100YuvToRgb(hdr_yuv_gamma);
		Color hdr_rgb = hlgInvOetf(hdr_rgb_gamma);
		float hdr_y_nits = bt2100Luminance(hdr_rgb);

		size_t pixel_idx = x + y * map_width;
		reinterpret_cast<uint8_t*>(dest->data)[pixel_idx] =
		encodeRecovery(y_sdr_nits, y_hdr_nits, hdr_ratio);
		encodeRecovery(sdr_y_nits, hdr_y_nits, hdr_ratio);
		}
		}

		@@ -367,7 +374,8 @@ status_t RecoveryMap::applyRecoveryMap(jr_uncompressed_ptr uncompressed_yuv_420_
		Color rgb_hdr = applyRecovery(rgb_sdr, recovery, hdr_ratio);

		Color rgbp_hdr = hlgOetf(rgb_hdr);
		Color ypuv_hdr = bt2100RgbToYuv(rgbp_hdr);
		// TODO: actually just leave in RGB and convert to RGBA1010102 instead.
		Color ypuv_hdr = srgbRgbToYuv(rgbp_hdr);

		reinterpret_cast<uint16_t*>(dest->data)[pixel_y_idx] = ypuv_hdr.r;
		reinterpret_cast<uint16_t*>(dest->data)[pixel_count + pixel_uv_idx] = ypuv_hdr.g;

libs/jpegrecoverymap/recoverymapmath.cpp

+127 −43

Original line number	Diff line number	Diff line
		@@ -20,42 +20,102 @@

		namespace android::recoverymap {

		static const float kBt2100R = 0.2627f, kBt2100G = 0.6780f, kBt2100B = 0.0593f;
		static const float kBt2100Cb = 1.8814f, kBt2100Cr = 1.4746f;
		////////////////////////////////////////////////////////////////////////////////
		// sRGB transformations

		static const float kSrgbR = 0.299f, kSrgbG = 0.587f, kSrgbB = 0.114f;

		Color bt2100RgbToYuv(Color e) {
		float yp = kBt2100R * e.r + kBt2100G * e.g + kBt2100B * e.b;
		return {{{yp, (e.b - yp) / kBt2100Cb, (e.r - yp) / kBt2100Cr }}};
		float srgbLuminance(Color e) {
		return kSrgbR * e.r + kSrgbG * e.g + kSrgbB * e.b;
		}

		static const float kSrgbRCr = 1.402f, kSrgbGCb = 0.34414f, kSrgbGCr = 0.71414f, kSrgbBCb = 1.772f;

		Color srgbYuvToRgb(Color e) {
		return {{{ e.y + kSrgbRCr * e.v, e.y - kSrgbGCb * e.u - kSrgbGCr * e.v, e.y + kSrgbBCb * e.u }}};
		Color srgbYuvToRgb(Color e_gamma) {
		return {{{ e_gamma.y + kSrgbRCr * e_gamma.v,
		e_gamma.y - kSrgbGCb * e_gamma.u - kSrgbGCr * e_gamma.v,
		e_gamma.y + kSrgbBCb * e_gamma.u }}};
		}

		static const float kSrgbUR = -0.1687f, kSrgbUG = -0.3313f, kSrgbUB = 0.5f;
		static const float kSrgbVR = 0.5f, kSrgbVG = -0.4187f, kSrgbVB = -0.0813f;

		Color srgbRgbToYuv(Color e_gamma) {
		return {{{ kSrgbR * e_gamma.r + kSrgbG * e_gamma.g + kSrgbB * e_gamma.b,
		kSrgbUR * e_gamma.r + kSrgbUG * e_gamma.g + kSrgbUB * e_gamma.b,
		kSrgbVR * e_gamma.r + kSrgbVG * e_gamma.g + kSrgbVB * e_gamma.b }}};
		}

		float srgbInvOetf(float e) {
		if (e <= 0.04045f) {
		return e / 12.92f;
		float srgbInvOetf(float e_gamma) {
		if (e_gamma <= 0.04045f) {
		return e_gamma / 12.92f;
		} else {
		return pow((e + 0.055f) / 1.055f, 2.4);
		return pow((e_gamma + 0.055f) / 1.055f, 2.4);
		}
		}

		Color srgbInvOetf(Color e) {
		return {{{ srgbInvOetf(e.r), srgbInvOetf(e.g), srgbInvOetf(e.b) }}};
		Color srgbInvOetf(Color e_gamma) {
		return {{{ srgbInvOetf(e_gamma.r),
		srgbInvOetf(e_gamma.g),
		srgbInvOetf(e_gamma.b) }}};
		}

		static const float kHlgA = 0.17883277f, kHlgB = 0.28466892f, kHlgC = 0.55991073;

		float hlgInvOetf(float e) {
		if (e <= 0.5f) {
		return pow(e, 2.0f) / 3.0f;
		} else {
		return (exp((e - kHlgC) / kHlgA) + kHlgB) / 12.0f;
		////////////////////////////////////////////////////////////////////////////////
		// Display-P3 transformations



		////////////////////////////////////////////////////////////////////////////////
		// BT.2100 transformations - according to ITU-R BT.2100-2

		static const float kBt2100R = 0.2627f, kBt2100G = 0.6780f, kBt2100B = 0.0593f;

		float bt2100Luminance(Color e) {
		return kBt2100R * e.r + kBt2100G * e.g + kBt2100B * e.b;
		}

		static const float kBt2100Cb = 1.8814f, kBt2100Cr = 1.4746f;

		Color bt2100RgbToYuv(Color e_gamma) {
		float y_gamma = bt2100Luminance(e_gamma);
		return {{{ y_gamma,
		(e_gamma.b - y_gamma) / kBt2100Cb,
		(e_gamma.r - y_gamma) / kBt2100Cr }}};
		}

		// Derived from the reverse of bt2100RgbToYuv. The derivation for R and B are
		// pretty straight forward; we just reverse the formulas for U and V above. But
		// deriving the formula for G is a bit more complicated:
		//
		// Start with equation for luminance:
		// Y = kBt2100R * R + kBt2100G * G + kBt2100B * B
		// Solve for G:
		// G = (Y - kBt2100R * R - kBt2100B * B) / kBt2100B
		// Substitute equations for R and B in terms YUV:
		// G = (Y - kBt2100R * (Y + kBt2100Cr * V) - kBt2100B * (Y + kBt2100Cb * U)) / kBt2100B
		// Simplify:
		// G = Y * ((1 - kBt2100R - kBt2100B) / kBt2100G)
		// + U * (kBt2100B * kBt2100Cb / kBt2100G)
		// + V * (kBt2100R * kBt2100Cr / kBt2100G)
		//
		// We then get the following coeficients for calculating G from YUV:
		//
		// Coef for Y = (1 - kBt2100R - kBt2100B) / kBt2100G = 1
		// Coef for U = kBt2100B * kBt2100Cb / kBt2100G = kBt2100GCb = ~0.1645
		// Coef for V = kBt2100R * kBt2100Cr / kBt2100G = kBt2100GCr = ~0.5713

		static const float kBt2100GCb = kBt2100B * kBt2100Cb / kBt2100G;
		static const float kBt2100GCr = kBt2100R * kBt2100Cr / kBt2100G;

		Color bt2100YuvToRgb(Color e_gamma) {
		return {{{ e_gamma.y + kBt2100Cr * e_gamma.v,
		e_gamma.y - kBt2100GCb * e_gamma.u - kBt2100GCr * e_gamma.v,
		e_gamma.y + kBt2100Cb * e_gamma.u }}};
		}

		static const float kHlgA = 0.17883277f, kHlgB = 0.28466892f, kHlgC = 0.55991073;

		static float hlgOetf(float e) {
		if (e <= 1.0f/12.0f) {
		return sqrt(3.0f * e);
		@@ -68,6 +128,28 @@ Color hlgOetf(Color e) {
		return {{{ hlgOetf(e.r), hlgOetf(e.g), hlgOetf(e.b) }}};
		}

		float hlgInvOetf(float e_gamma) {
		if (e_gamma <= 0.5f) {
		return pow(e_gamma, 2.0f) / 3.0f;
		} else {
		return (exp((e_gamma - kHlgC) / kHlgA) + kHlgB) / 12.0f;
		}
		}

		Color hlgInvOetf(Color e_gamma) {
		return {{{ hlgInvOetf(e_gamma.r),
		hlgInvOetf(e_gamma.g),
		hlgInvOetf(e_gamma.b) }}};
		}


		////////////////////////////////////////////////////////////////////////////////
		// Color conversions


		////////////////////////////////////////////////////////////////////////////////
		// Recovery map calculations

		uint8_t encodeRecovery(float y_sdr, float y_hdr, float hdr_ratio) {
		float gain = 1.0f;
		if (y_sdr > 0.0f) {
		@@ -137,40 +219,42 @@ Color getYuv420Pixel(jr_uncompressed_ptr image, size_t x, size_t y) {
		(static_cast<float>(v_uint) - 128.0f) / 255.0f }}};
		}

		typedef float (*sampleComponentFn)(jr_uncompressed_ptr, size_t, size_t);
		Color getP010Pixel(jr_uncompressed_ptr image, size_t x, size_t y) {
		size_t pixel_count = image->width * image->height;

		size_t pixel_y_idx = x + y * image->width;
		size_t pixel_uv_idx = x / 2 + (y / 2) * (image->width / 2);

		uint16_t y_uint = reinterpret_cast<uint16_t*>(image->data)[pixel_y_idx];
		uint16_t u_uint = reinterpret_cast<uint16_t>(image->data)[pixel_count + pixel_uv_idx 2];
		uint16_t v_uint = reinterpret_cast<uint16_t>(image->data)[pixel_count + pixel_uv_idx 2 + 1];

		// Conversions include taking narrow-range into account.
		return {{{ static_cast<float>(y_uint) / 940.0f,
		(static_cast<float>(u_uint) - 64.0f) / 940.0f - 0.5f,
		(static_cast<float>(v_uint) - 64.0f) / 940.0f - 0.5f }}};
		}

		typedef Color (*getPixelFn)(jr_uncompressed_ptr, size_t, size_t);

		static float sampleComponent(jr_uncompressed_ptr image, size_t map_scale_factor, size_t x, size_t y,
		sampleComponentFn sample_fn) {
		float e = 0.0f;
		static Color samplePixels(jr_uncompressed_ptr image, size_t map_scale_factor, size_t x, size_t y,
		getPixelFn get_pixel_fn) {
		Color e = {{{ 0.0f, 0.0f, 0.0f }}};
		for (size_t dy = 0; dy < map_scale_factor; ++dy) {
		for (size_t dx = 0; dx < map_scale_factor; ++dx) {
		e += sample_fn(image, x * map_scale_factor + dx, y * map_scale_factor + dy);
		e += get_pixel_fn(image, x * map_scale_factor + dx, y * map_scale_factor + dy);
		}
		}

		return e / static_cast<float>(map_scale_factor * map_scale_factor);
		}

		static float getYuv420Y(jr_uncompressed_ptr image, size_t x, size_t y) {
		size_t pixel_idx = x + y * image->width;
		uint8_t y_uint = reinterpret_cast<uint8_t*>(image->data)[pixel_idx];
		return static_cast<float>(y_uint) / 255.0f;
		}


		float sampleYuv420Y(jr_uncompressed_ptr image, size_t map_scale_factor, size_t x, size_t y) {
		return sampleComponent(image, map_scale_factor, x, y, getYuv420Y);
		}

		static float getP010Y(jr_uncompressed_ptr image, size_t x, size_t y) {
		size_t pixel_idx = x + y * image->width;
		uint8_t y_uint = reinterpret_cast<uint16_t*>(image->data)[pixel_idx];
		// Expecting narrow range input
		return (static_cast<float>(y_uint) - 64.0f) / 960.0f;
		Color sampleYuv420(jr_uncompressed_ptr image, size_t map_scale_factor, size_t x, size_t y) {
		return samplePixels(image, map_scale_factor, x, y, getYuv420Pixel);
		}

		float sampleP010Y(jr_uncompressed_ptr image, size_t map_scale_factor, size_t x, size_t y) {
		return sampleComponent(image, map_scale_factor, x, y, getP010Y);
		Color sampleP010(jr_uncompressed_ptr image, size_t map_scale_factor, size_t x, size_t y) {
		return samplePixels(image, map_scale_factor, x, y, getP010Pixel);
		}

		} // namespace android::recoverymap

libs/jpegrecoverymap/tests/Android.bp

+8 −0

Original line number	Diff line number	Diff line
		@@ -27,7 +27,15 @@ cc_test {
		srcs: [
		"recoverymap_test.cpp",
		],
		shared_libs: [
		"libimage_io",
		"libjpeg",
		"liblog",
		],
		static_libs: [
		"libgtest",
		"libjpegdecoder",
		"libjpegencoder",
		"libjpegrecoverymap",
		],
		}

libs/jpegrecoverymap/tests/recoverymap_test.cpp

+27 −3

Original line number	Diff line number	Diff line
		@@ -14,9 +14,33 @@
		* limitations under the License.
		*/

		#include <gtest/gtest.h>
		#include <jpegrecoverymap/recoverymap.h>

		namespace android {
		namespace android::recoverymap {

		// Add new tests here.
		} // namespace android
		class RecoveryMapTest : public testing::Test {
		public:
		RecoveryMapTest();
		~RecoveryMapTest();
		protected:
		virtual void SetUp();
		virtual void TearDown();
		};

		RecoveryMapTest::RecoveryMapTest() {}
		RecoveryMapTest::~RecoveryMapTest() {}

		void RecoveryMapTest::SetUp() {}
		void RecoveryMapTest::TearDown() {}

		TEST_F(RecoveryMapTest, build) {
		// Force all of the recovery map lib to be linked by calling all public functions.
		RecoveryMap recovery_map;
		recovery_map.encodeJPEGR(nullptr, nullptr, nullptr, 0, nullptr);
		recovery_map.encodeJPEGR(nullptr, nullptr, nullptr, nullptr);
		recovery_map.encodeJPEGR(nullptr, nullptr, nullptr);
		recovery_map.decodeJPEGR(nullptr, nullptr, nullptr, false);
		}

		} // namespace android::recoverymap