| /* |
| * Copyright (C) 2017 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #include "Color.h" |
| |
| #include <utils/Log.h> |
| #include <ui/ColorSpace.h> |
| |
| #include <algorithm> |
| #include <cmath> |
| |
| namespace android { |
| namespace uirenderer { |
| |
| static inline bool almostEqual(float a, float b) { |
| return std::abs(a - b) < 1e-2f; |
| } |
| |
| bool transferFunctionCloseToSRGB(const SkColorSpace* colorSpace) { |
| if (colorSpace == nullptr) return true; |
| if (colorSpace->isSRGB()) return true; |
| |
| SkColorSpaceTransferFn transferFunction; |
| if (colorSpace->isNumericalTransferFn(&transferFunction)) { |
| // sRGB transfer function params: |
| const float sRGBParamA = 1 / 1.055f; |
| const float sRGBParamB = 0.055f / 1.055f; |
| const float sRGBParamC = 1 / 12.92f; |
| const float sRGBParamD = 0.04045f; |
| const float sRGBParamE = 0.0f; |
| const float sRGBParamF = 0.0f; |
| const float sRGBParamG = 2.4f; |
| |
| // This comparison will catch Display P3 |
| return almostEqual(sRGBParamA, transferFunction.fA) && |
| almostEqual(sRGBParamB, transferFunction.fB) && |
| almostEqual(sRGBParamC, transferFunction.fC) && |
| almostEqual(sRGBParamD, transferFunction.fD) && |
| almostEqual(sRGBParamE, transferFunction.fE) && |
| almostEqual(sRGBParamF, transferFunction.fF) && |
| almostEqual(sRGBParamG, transferFunction.fG); |
| } |
| |
| return false; |
| } |
| |
| SkColorType PixelFormatToColorType(android_pixel_format pixelFormat) { |
| switch (pixelFormat) { |
| case HAL_PIXEL_FORMAT_RGBA_8888: |
| case HAL_PIXEL_FORMAT_BGRA_8888: |
| return SkColorType::kN32_SkColorType; |
| case HAL_PIXEL_FORMAT_RGBA_FP16: |
| return SkColorType::kRGBA_F16_SkColorType; |
| case HAL_PIXEL_FORMAT_RGBA_1010102: |
| return SkColorType::kRGBA_1010102_SkColorType; |
| default: |
| ALOGW("Unsupported pixel format: %d, return kN32 by default", pixelFormat); |
| return SkColorType::kN32_SkColorType; |
| } |
| } |
| |
| android::PixelFormat ColorTypeToPixelFormat(SkColorType colorType) { |
| switch (colorType) { |
| case kRGBA_8888_SkColorType: |
| return PIXEL_FORMAT_RGBA_8888; |
| case kRGBA_F16_SkColorType: |
| return PIXEL_FORMAT_RGBA_FP16; |
| case kRGB_565_SkColorType: |
| return PIXEL_FORMAT_RGB_565; |
| case kRGB_888x_SkColorType: |
| return PIXEL_FORMAT_RGBX_8888; |
| case kRGBA_1010102_SkColorType: |
| return PIXEL_FORMAT_RGBA_1010102; |
| case kARGB_4444_SkColorType: |
| return PIXEL_FORMAT_RGBA_4444; |
| default: |
| ALOGW("Unsupported colorType: %d, return RGBA_8888 by default", (int)colorType); |
| return PIXEL_FORMAT_RGBA_8888; |
| } |
| } |
| |
| SkColorSpace::Gamut DataSpaceToColorGamut(android_dataspace dataSpace) { |
| switch (dataSpace & HAL_DATASPACE_STANDARD_MASK) { |
| case HAL_DATASPACE_STANDARD_BT709: |
| return SkColorSpace::kSRGB_Gamut; |
| case HAL_DATASPACE_STANDARD_BT2020: |
| return SkColorSpace::kRec2020_Gamut; |
| case HAL_DATASPACE_STANDARD_DCI_P3: |
| return SkColorSpace::kDCIP3_D65_Gamut; |
| case HAL_DATASPACE_STANDARD_ADOBE_RGB: |
| return SkColorSpace::kAdobeRGB_Gamut; |
| case HAL_DATASPACE_STANDARD_UNSPECIFIED: |
| case HAL_DATASPACE_STANDARD_BT601_625: |
| case HAL_DATASPACE_STANDARD_BT601_625_UNADJUSTED: |
| case HAL_DATASPACE_STANDARD_BT601_525: |
| case HAL_DATASPACE_STANDARD_BT601_525_UNADJUSTED: |
| case HAL_DATASPACE_STANDARD_BT2020_CONSTANT_LUMINANCE: |
| case HAL_DATASPACE_STANDARD_BT470M: |
| case HAL_DATASPACE_STANDARD_FILM: |
| default: |
| ALOGW("Unsupported Gamut: %d, return SRGB gamut by default", dataSpace); |
| return SkColorSpace::kSRGB_Gamut; |
| } |
| } |
| |
| sk_sp<SkColorSpace> DataSpaceToColorSpace(android_dataspace dataspace) { |
| |
| SkColorSpace::Gamut gamut; |
| switch (dataspace & HAL_DATASPACE_STANDARD_MASK) { |
| case HAL_DATASPACE_STANDARD_BT709: |
| gamut = SkColorSpace::kSRGB_Gamut; |
| break; |
| case HAL_DATASPACE_STANDARD_BT2020: |
| gamut = SkColorSpace::kRec2020_Gamut; |
| break; |
| case HAL_DATASPACE_STANDARD_DCI_P3: |
| gamut = SkColorSpace::kDCIP3_D65_Gamut; |
| break; |
| case HAL_DATASPACE_STANDARD_ADOBE_RGB: |
| gamut = SkColorSpace::kAdobeRGB_Gamut; |
| break; |
| case HAL_DATASPACE_STANDARD_UNSPECIFIED: |
| return nullptr; |
| case HAL_DATASPACE_STANDARD_BT601_625: |
| case HAL_DATASPACE_STANDARD_BT601_625_UNADJUSTED: |
| case HAL_DATASPACE_STANDARD_BT601_525: |
| case HAL_DATASPACE_STANDARD_BT601_525_UNADJUSTED: |
| case HAL_DATASPACE_STANDARD_BT2020_CONSTANT_LUMINANCE: |
| case HAL_DATASPACE_STANDARD_BT470M: |
| case HAL_DATASPACE_STANDARD_FILM: |
| default: |
| ALOGW("Unsupported Gamut: %d", dataspace); |
| return nullptr; |
| } |
| |
| switch (dataspace & HAL_DATASPACE_TRANSFER_MASK) { |
| case HAL_DATASPACE_TRANSFER_LINEAR: |
| return SkColorSpace::MakeRGB(SkColorSpace::kLinear_RenderTargetGamma, gamut); |
| case HAL_DATASPACE_TRANSFER_SRGB: |
| return SkColorSpace::MakeRGB(SkColorSpace::kSRGB_RenderTargetGamma, gamut); |
| case HAL_DATASPACE_TRANSFER_GAMMA2_2: |
| return SkColorSpace::MakeRGB({2.2f, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f}, gamut); |
| case HAL_DATASPACE_TRANSFER_GAMMA2_6: |
| return SkColorSpace::MakeRGB({2.6f, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f}, gamut); |
| case HAL_DATASPACE_TRANSFER_GAMMA2_8: |
| return SkColorSpace::MakeRGB({2.8f, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f}, gamut); |
| case HAL_DATASPACE_TRANSFER_UNSPECIFIED: |
| return nullptr; |
| case HAL_DATASPACE_TRANSFER_SMPTE_170M: |
| case HAL_DATASPACE_TRANSFER_ST2084: |
| case HAL_DATASPACE_TRANSFER_HLG: |
| default: |
| ALOGW("Unsupported Gamma: %d", dataspace); |
| return nullptr; |
| } |
| } |
| |
| template<typename T> |
| static constexpr T clamp(T x, T min, T max) { |
| return x < min ? min : x > max ? max : x; |
| } |
| |
| //static const float2 ILLUMINANT_D50_XY = {0.34567f, 0.35850f}; |
| static const float3 ILLUMINANT_D50_XYZ = {0.964212f, 1.0f, 0.825188f}; |
| static const mat3 BRADFORD = mat3{ |
| float3{ 0.8951f, -0.7502f, 0.0389f}, |
| float3{ 0.2664f, 1.7135f, -0.0685f}, |
| float3{-0.1614f, 0.0367f, 1.0296f} |
| }; |
| |
| static mat3 adaptation(const mat3& matrix, const float3& srcWhitePoint, const float3& dstWhitePoint) { |
| float3 srcLMS = matrix * srcWhitePoint; |
| float3 dstLMS = matrix * dstWhitePoint; |
| return inverse(matrix) * mat3{dstLMS / srcLMS} * matrix; |
| } |
| |
| namespace LabColorSpace { |
| |
| static constexpr float A = 216.0f / 24389.0f; |
| static constexpr float B = 841.0f / 108.0f; |
| static constexpr float C = 4.0f / 29.0f; |
| static constexpr float D = 6.0f / 29.0f; |
| |
| float3 toXyz(const Lab& lab) { |
| float3 v { lab.L, lab.a, lab.b }; |
| v[0] = clamp(v[0], 0.0f, 100.0f); |
| v[1] = clamp(v[1], -128.0f, 128.0f); |
| v[2] = clamp(v[2], -128.0f, 128.0f); |
| |
| float fy = (v[0] + 16.0f) / 116.0f; |
| float fx = fy + (v[1] * 0.002f); |
| float fz = fy - (v[2] * 0.005f); |
| float X = fx > D ? fx * fx * fx : (1.0f / B) * (fx - C); |
| float Y = fy > D ? fy * fy * fy : (1.0f / B) * (fy - C); |
| float Z = fz > D ? fz * fz * fz : (1.0f / B) * (fz - C); |
| |
| v[0] = X * ILLUMINANT_D50_XYZ[0]; |
| v[1] = Y * ILLUMINANT_D50_XYZ[1]; |
| v[2] = Z * ILLUMINANT_D50_XYZ[2]; |
| |
| return v; |
| } |
| |
| Lab fromXyz(const float3& v) { |
| float X = v[0] / ILLUMINANT_D50_XYZ[0]; |
| float Y = v[1] / ILLUMINANT_D50_XYZ[1]; |
| float Z = v[2] / ILLUMINANT_D50_XYZ[2]; |
| |
| float fx = X > A ? pow(X, 1.0f / 3.0f) : B * X + C; |
| float fy = Y > A ? pow(Y, 1.0f / 3.0f) : B * Y + C; |
| float fz = Z > A ? pow(Z, 1.0f / 3.0f) : B * Z + C; |
| |
| float L = 116.0f * fy - 16.0f; |
| float a = 500.0f * (fx - fy); |
| float b = 200.0f * (fy - fz); |
| |
| return Lab { |
| clamp(L, 0.0f, 100.0f), |
| clamp(a, -128.0f, 128.0f), |
| clamp(b, -128.0f, 128.0f) |
| }; |
| } |
| |
| }; |
| |
| Lab sRGBToLab(SkColor color) { |
| auto colorSpace = ColorSpace::sRGB(); |
| float3 rgb; |
| rgb.r = SkColorGetR(color) / 255.0f; |
| rgb.g = SkColorGetG(color) / 255.0f; |
| rgb.b = SkColorGetB(color) / 255.0f; |
| float3 xyz = colorSpace.rgbToXYZ(rgb); |
| float3 srcXYZ = ColorSpace::XYZ(float3{colorSpace.getWhitePoint(), 1}); |
| xyz = adaptation(BRADFORD, srcXYZ, ILLUMINANT_D50_XYZ) * xyz; |
| return LabColorSpace::fromXyz(xyz); |
| } |
| |
| SkColor LabToSRGB(const Lab& lab, SkAlpha alpha) { |
| auto colorSpace = ColorSpace::sRGB(); |
| float3 xyz = LabColorSpace::toXyz(lab); |
| float3 dstXYZ = ColorSpace::XYZ(float3{colorSpace.getWhitePoint(), 1}); |
| xyz = adaptation(BRADFORD, ILLUMINANT_D50_XYZ, dstXYZ) * xyz; |
| float3 rgb = colorSpace.xyzToRGB(xyz); |
| return SkColorSetARGB(alpha, |
| static_cast<uint8_t>(rgb.r * 255), |
| static_cast<uint8_t>(rgb.g * 255), |
| static_cast<uint8_t>(rgb.b * 255)); |
| } |
| |
| }; // namespace uirenderer |
| }; // namespace android |