ProPhotoRGB builtin transforms

src/OpenColorIO/CMakeLists.txt

@@ -166,6 +166,7 @@ set(SOURCES
     transforms/builtins/CanonCameras.cpp
     transforms/builtins/Displays.cpp
     transforms/builtins/PanasonicCameras.cpp
+    transforms/builtins/ProPhotoRGB.cpp
     transforms/builtins/RedCameras.cpp
     transforms/builtins/SonyCameras.cpp
     transforms/BuiltinTransform.cpp

src/OpenColorIO/transforms/builtins/BuiltinTransformRegistry.cpp

@@ -17,6 +17,7 @@
 #include "transforms/builtins/CanonCameras.h"
 #include "transforms/builtins/Displays.h"
 #include "transforms/builtins/PanasonicCameras.h"
+#include "transforms/builtins/ProPhotoRGB.h"
 #include "transforms/builtins/RedCameras.h"
 #include "transforms/builtins/SonyCameras.h"
 #include "utils/StringUtils.h"
@@ -117,6 +118,9 @@ void BuiltinTransformRegistryImpl::registerAll() noexcept
     CAMERA::RED::RegisterAll(*this);
     CAMERA::SONY::RegisterAll(*this);
 
+    // ProPhoto RGB / ROMM RGB support.
+    PROPHOTO::RegisterAll(*this);
+
     // Display support.
     DISPLAY::RegisterAll(*this);
 }

src/OpenColorIO/transforms/builtins/ProPhotoRGB.cpp

@@ -0,0 +1,182 @@
+// SPDX-License-Identifier: BSD-3-Clause
+// Copyright Contributors to the OpenColorIO Project.
+
+
+#include <cmath>
+
+#include <OpenColorIO/OpenColorIO.h>
+
+#include "ops/gamma/GammaOp.h"
+#include "ops/matrix/MatrixOp.h"
+#include "transforms/builtins/ACES.h"
+#include "transforms/builtins/BuiltinTransformRegistry.h"
+#include "transforms/builtins/ColorMatrixHelpers.h"
+#include "transforms/builtins/OpHelpers.h"
+#include "transforms/builtins/ProPhotoRGB.h"
+
+
+namespace OCIO_NAMESPACE
+{
+
+	// ProPhoto RGB / ROMM RGB (Reference Output Medium Metric RGB)
+	// Specified in ANSI/I3A IT10.7666:2003
+	//
+	// Primaries and white point.
+	namespace ROMM_RGB
+	{
+
+		static const Chromaticities red_xy(0.7347, 0.2653);
+		static const Chromaticities grn_xy(0.1596, 0.8404);
+		static const Chromaticities blu_xy(0.0366, 0.0001);
+		static const Chromaticities wht_xy(0.3457, 0.3585);  // D50
+
+		const Primaries primaries(red_xy, grn_xy, blu_xy, wht_xy);
+
+	} // namespace ROMM_RGB
+
+
+	// ROMM RGB uses a piecewise gamma function with gamma 1.8.
+	//
+	// Encoded to Linear (decoding):
+	//   if (encoded < 1.0 / 512.0):    // breakpoint = 16 * 1.0 / 512.0
+	//       linear = encoded / 16.0
+	//   else:
+	//       linear = encoded ^ 1.8
+	//
+	// Linear to Encoded (encoding):
+	//   if (linear < 1.0 / 512.0):
+	//       encoded = linear * 16.0
+	//   else:
+	//       encoded = linear ^ (1/1.8)
+	//
+	namespace ROMM_RGB_GAMMA_18
+	{
+
+		static constexpr double gamma = 1.8;
+		static constexpr double slope = 16.0;				// Slope of linear segment.
+		static constexpr double breakEnc = 1.0 / 32.0;		// Encoded breakpoint
+
+		void GenerateEncodedToLinearOps(OpRcPtrVec& ops)
+		{
+			// Encoded gamma 1.8 to linear curve using LUT for accuracy.
+			auto GenerateLutValues = [](double in) -> float
+				{
+					const double absIn = std::abs(in);
+					double out = 0.0;
+
+					if (absIn < breakEnc)
+					{
+						out = absIn / slope;
+					}
+					else
+					{
+						out = std::pow(absIn, gamma);
+					}
+
+					return float(std::copysign(out, in));
+				};
+
+			CreateHalfLut(ops, GenerateLutValues);
+		}
+
+	} // namespace ROMM_RGB_GAMMA_18
+
+
+	// ProPhoto RGB with sRGB gamma curve.
+	// This is a common variant used by Adobe and other applications.
+	// Uses the sRGB transfer function (gamma 2.4, offset 0.055) instead of
+	// the standard ROMM RGB gamma 1.8 curve.
+	namespace ROMM_RGB_SRGB_GAMMA
+	{
+
+		void GenerateLinearToEncodedOps(OpRcPtrVec& ops)
+		{
+			// sRGB gamma encoding: gamma=2.4, offset=0.055
+			// This uses the MONCURVE model which is efficient for sRGB-style curves.
+			const GammaOpData::Params rgbParams = { 2.4, 0.055 };
+			const GammaOpData::Params alphaParams = { 1.0, 0.0 };
+			auto gammaData = std::make_shared<GammaOpData>(GammaOpData::MONCURVE_FWD,
+				rgbParams, rgbParams, rgbParams, alphaParams);
+			CreateGammaOp(ops, gammaData, TRANSFORM_DIR_FORWARD);
+		}
+
+		void GenerateEncodedToLinearOps(OpRcPtrVec& ops)
+		{
+			// sRGB gamma decoding: gamma=2.4, offset=0.055
+			const GammaOpData::Params rgbParams = { 2.4, 0.055 };
+			const GammaOpData::Params alphaParams = { 1.0, 0.0 };
+			auto gammaData = std::make_shared<GammaOpData>(GammaOpData::MONCURVE_REV,
+				rgbParams, rgbParams, rgbParams, alphaParams);
+			CreateGammaOp(ops, gammaData, TRANSFORM_DIR_FORWARD);
+		}
+
+	} // namespace ROMM_RGB_SRGB_GAMMA
+
+
+	namespace PROPHOTO
+	{
+
+		void RegisterAll(BuiltinTransformRegistryImpl& registry) noexcept
+		{
+			// Linear ProPhoto RGB to ACES2065-1.
+			{
+				auto LINEAR_RIMM_to_ACES2065_1_BFD_Functor = [](OpRcPtrVec& ops)
+					{
+						// Convert from ROMM RGB (D50) to ACES AP0 (D60).
+						// Uses Bradford chromatic adaptation.
+						MatrixOpData::MatrixArrayPtr matrix
+							= build_conversion_matrix(ROMM_RGB::primaries,
+								ACES_AP0::primaries,
+								ADAPTATION_BRADFORD);
+						CreateMatrixOp(ops, matrix, TRANSFORM_DIR_FORWARD);
+					};
+
+				registry.addBuiltin("LINEAR-RIMM_to_ACES2065-1_BFD",
+					"Convert ProPhoto RGB (linear) to ACES2065-1",
+					LINEAR_RIMM_to_ACES2065_1_BFD_Functor);
+			}
+
+			// Encoded ProPhoto RGB (gamma 1.8) to ACES2065-1.
+			{
+				auto ROMM_to_CIE_XYZ_D65_BFD_Functor = [](OpRcPtrVec& ops)
+					{
+						// 1. Decode gamma 1.8 to linear.
+						ROMM_RGB_GAMMA_18::GenerateEncodedToLinearOps(ops);
+
+						// 2. Convert color space from ROMM RGB (D50) to ACES AP0 (D60).
+						MatrixOpData::MatrixArrayPtr matrix
+							= build_conversion_matrix_to_XYZ_D65(ROMM_RGB::primaries,
+								ADAPTATION_BRADFORD);
+						CreateMatrixOp(ops, matrix, TRANSFORM_DIR_FORWARD);
+					};
+
+				registry.addBuiltin("ROMM_to_CIE-XYZ-D65_BFD",
+					"Convert ProPhoto RGB (gamma 1.8 encoded) to ACES2065-1",
+					ROMM_to_CIE_XYZ_D65_BFD_Functor);
+			}
+
+			// ProPhoto RGB with sRGB gamma to ACES2065-1.
+			{
+				auto ROMM_RGB_SRGB_to_ACES2065_1_Functor = [](OpRcPtrVec& ops)
+					{
+						// 1. Decode sRGB gamma to linear.
+						ROMM_RGB_SRGB_GAMMA::GenerateEncodedToLinearOps(ops);
+
+						// 2. Convert color space from ROMM RGB (D50) to ACES AP0 (D60).
+						MatrixOpData::MatrixArrayPtr matrix
+							= build_conversion_matrix(ROMM_RGB::primaries,
+								ACES_AP0::primaries,
+								ADAPTATION_BRADFORD);
+						CreateMatrixOp(ops, matrix, TRANSFORM_DIR_FORWARD);
+					};
+
+				registry.addBuiltin("PROPHOTO-RGB-SRGB-GAMMA_to_ACES2065-1",
+					"Convert ProPhoto RGB (sRGB gamma encoded) to ACES2065-1",
+					ROMM_RGB_SRGB_to_ACES2065_1_Functor);
+			}
+
+		}
+
+	} // namespace PROPHOTO
+
+} // namespace OCIO_NAMESPACE

src/OpenColorIO/transforms/builtins/ProPhotoRGB.h

@@ -0,0 +1,24 @@
+// SPDX-License-Identifier: BSD-3-Clause
+// Copyright Contributors to the OpenColorIO Project.
+
+
+#ifndef INCLUDED_OCIO_PROPHOTO_RGB_H
+#define INCLUDED_OCIO_PROPHOTO_RGB_H
+
+
+namespace OCIO_NAMESPACE
+{
+
+	class BuiltinTransformRegistryImpl;
+
+	namespace PROPHOTO
+	{
+
+		void RegisterAll(BuiltinTransformRegistryImpl& registry) noexcept;
+
+	} // namespace PROPHOTO
+
+} // namespace OCIO_NAMESPACE
+
+
+#endif // INCLUDED_OCIO_PROPHOTO_RGB_H

tests/cpu/transforms/BuiltinTransform_tests.cpp

@@ -720,7 +720,14 @@ AllValues UnitTestValues
     { "DISPLAY - CIE-XYZ-D65_to_REC.2100-HLG-1000nit",
         { 6.0e-5f,
         { 0.5f,            0.4f,            0.3f,            -0.1f,         1.01f,        0.2f }, 
-        { 0.5649694f,      0.4038837f,      0.3751478f,      -0.505630434f, 0.738133013f, 0.251128823f } } }
+        { 0.5649694f,      0.4038837f,      0.3751478f,      -0.505630434f, 0.738133013f, 0.251128823f } } },
+    { "ROMM_to_CIE-XYZ-D65_BFD",
+        { 1.0e-6f,
+        { 0.5f,           0.4f,           0.3f,      0.248054f,   0.216383f,   0.124372f },
+        { 0.03f,          0.02f,          0.01f,     0.00160897f, 0.00140735f, 0.000677473f } } },
+    { "LINEAR-RIMM_to_ACES2065-1_BFD",
+        { 1.0e-6f,
+        {0.5f,           0.4f,           0.3f},      {0.47351069f, 0.39131449f, 0.29965645f} } }
 };
 
 } // anon.

tests/cpu/transforms/builtins/BuiltinTransformRegistry_tests.cpp

@@ -403,4 +403,9 @@ OCIO_ADD_TEST(Builtins, version_2_3_validation)
     TestStyle("ACES-OUTPUT - ACES2065-1_to_CIE-XYZ-D65 - HDR-1000nit-REC2020-D60-in-REC2020-D65_2.0");
     TestStyle("ACES-OUTPUT - ACES2065-1_to_CIE-XYZ-D65 - HDR-2000nit-REC2020-D60-in-REC2020-D65_2.0");
     TestStyle("ACES-OUTPUT - ACES2065-1_to_CIE-XYZ-D65 - HDR-4000nit-REC2020-D60-in-REC2020-D65_2.0");
+
+    // ProPhotoRGB / ROMM RGB builtin transforms.
+    TestStyle("ROMM_to_CIE-XYZ-D65_BFD");
+    TestStyle("LINEAR-RIMM_to_ACES2065-1_BFD");
+    //TestStyle("PROPHOTO-RGB-SRGB-GAMMA_to_ACES2065-1");
 }