| /* |
| * Copyright 2022 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. |
| */ |
| |
| #ifndef USE_BIG_ENDIAN |
| #define USE_BIG_ENDIAN true |
| #endif |
| |
| #include <ultrahdr/icc.h> |
| #include <vector> |
| #include <utils/Log.h> |
| |
| #ifndef FLT_MAX |
| #define FLT_MAX 0x1.fffffep127f |
| #endif |
| |
| namespace android::ultrahdr { |
| static void Matrix3x3_apply(const Matrix3x3* m, float* x) { |
| float y0 = x[0] * m->vals[0][0] + x[1] * m->vals[0][1] + x[2] * m->vals[0][2]; |
| float y1 = x[0] * m->vals[1][0] + x[1] * m->vals[1][1] + x[2] * m->vals[1][2]; |
| float y2 = x[0] * m->vals[2][0] + x[1] * m->vals[2][1] + x[2] * m->vals[2][2]; |
| x[0] = y0; |
| x[1] = y1; |
| x[2] = y2; |
| } |
| |
| bool Matrix3x3_invert(const Matrix3x3* src, Matrix3x3* dst) { |
| double a00 = src->vals[0][0], |
| a01 = src->vals[1][0], |
| a02 = src->vals[2][0], |
| a10 = src->vals[0][1], |
| a11 = src->vals[1][1], |
| a12 = src->vals[2][1], |
| a20 = src->vals[0][2], |
| a21 = src->vals[1][2], |
| a22 = src->vals[2][2]; |
| |
| double b0 = a00*a11 - a01*a10, |
| b1 = a00*a12 - a02*a10, |
| b2 = a01*a12 - a02*a11, |
| b3 = a20, |
| b4 = a21, |
| b5 = a22; |
| |
| double determinant = b0*b5 |
| - b1*b4 |
| + b2*b3; |
| |
| if (determinant == 0) { |
| return false; |
| } |
| |
| double invdet = 1.0 / determinant; |
| if (invdet > +FLT_MAX || invdet < -FLT_MAX || !isfinitef_((float)invdet)) { |
| return false; |
| } |
| |
| b0 *= invdet; |
| b1 *= invdet; |
| b2 *= invdet; |
| b3 *= invdet; |
| b4 *= invdet; |
| b5 *= invdet; |
| |
| dst->vals[0][0] = (float)( a11*b5 - a12*b4 ); |
| dst->vals[1][0] = (float)( a02*b4 - a01*b5 ); |
| dst->vals[2][0] = (float)( + b2 ); |
| dst->vals[0][1] = (float)( a12*b3 - a10*b5 ); |
| dst->vals[1][1] = (float)( a00*b5 - a02*b3 ); |
| dst->vals[2][1] = (float)( - b1 ); |
| dst->vals[0][2] = (float)( a10*b4 - a11*b3 ); |
| dst->vals[1][2] = (float)( a01*b3 - a00*b4 ); |
| dst->vals[2][2] = (float)( + b0 ); |
| |
| for (int r = 0; r < 3; ++r) |
| for (int c = 0; c < 3; ++c) { |
| if (!isfinitef_(dst->vals[r][c])) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| static Matrix3x3 Matrix3x3_concat(const Matrix3x3* A, const Matrix3x3* B) { |
| Matrix3x3 m = { { { 0,0,0 },{ 0,0,0 },{ 0,0,0 } } }; |
| for (int r = 0; r < 3; r++) |
| for (int c = 0; c < 3; c++) { |
| m.vals[r][c] = A->vals[r][0] * B->vals[0][c] |
| + A->vals[r][1] * B->vals[1][c] |
| + A->vals[r][2] * B->vals[2][c]; |
| } |
| return m; |
| } |
| |
| static void float_XYZD50_to_grid16_lab(const float* xyz_float, uint8_t* grid16_lab) { |
| float v[3] = { |
| xyz_float[0] / kD50_x, |
| xyz_float[1] / kD50_y, |
| xyz_float[2] / kD50_z, |
| }; |
| for (size_t i = 0; i < 3; ++i) { |
| v[i] = v[i] > 0.008856f ? cbrtf(v[i]) : v[i] * 7.787f + (16 / 116.0f); |
| } |
| const float L = v[1] * 116.0f - 16.0f; |
| const float a = (v[0] - v[1]) * 500.0f; |
| const float b = (v[1] - v[2]) * 200.0f; |
| const float Lab_unorm[3] = { |
| L * (1 / 100.f), |
| (a + 128.0f) * (1 / 255.0f), |
| (b + 128.0f) * (1 / 255.0f), |
| }; |
| // This will encode L=1 as 0xFFFF. This matches how skcms will interpret the |
| // table, but the spec appears to indicate that the value should be 0xFF00. |
| // https://crbug.com/skia/13807 |
| for (size_t i = 0; i < 3; ++i) { |
| reinterpret_cast<uint16_t*>(grid16_lab)[i] = |
| Endian_SwapBE16(float_round_to_unorm16(Lab_unorm[i])); |
| } |
| } |
| |
| std::string IccHelper::get_desc_string(const ultrahdr_transfer_function tf, |
| const ultrahdr_color_gamut gamut) { |
| std::string result; |
| switch (gamut) { |
| case ULTRAHDR_COLORGAMUT_BT709: |
| result += "sRGB"; |
| break; |
| case ULTRAHDR_COLORGAMUT_P3: |
| result += "Display P3"; |
| break; |
| case ULTRAHDR_COLORGAMUT_BT2100: |
| result += "Rec2020"; |
| break; |
| default: |
| result += "Unknown"; |
| break; |
| } |
| result += " Gamut with "; |
| switch (tf) { |
| case ULTRAHDR_TF_SRGB: |
| result += "sRGB"; |
| break; |
| case ULTRAHDR_TF_LINEAR: |
| result += "Linear"; |
| break; |
| case ULTRAHDR_TF_PQ: |
| result += "PQ"; |
| break; |
| case ULTRAHDR_TF_HLG: |
| result += "HLG"; |
| break; |
| default: |
| result += "Unknown"; |
| break; |
| } |
| result += " Transfer"; |
| return result; |
| } |
| |
| sp<DataStruct> IccHelper::write_text_tag(const char* text) { |
| uint32_t text_length = strlen(text); |
| uint32_t header[] = { |
| Endian_SwapBE32(kTAG_TextType), // Type signature |
| 0, // Reserved |
| Endian_SwapBE32(1), // Number of records |
| Endian_SwapBE32(12), // Record size (must be 12) |
| Endian_SwapBE32(SetFourByteTag('e', 'n', 'U', 'S')), // English USA |
| Endian_SwapBE32(2 * text_length), // Length of string in bytes |
| Endian_SwapBE32(28), // Offset of string |
| }; |
| |
| uint32_t total_length = text_length * 2 + sizeof(header); |
| total_length = (((total_length + 2) >> 2) << 2); // 4 aligned |
| sp<DataStruct> dataStruct = sp<DataStruct>::make(total_length); |
| |
| if (!dataStruct->write(header, sizeof(header))) { |
| ALOGE("write_text_tag(): error in writing data"); |
| return dataStruct; |
| } |
| |
| for (size_t i = 0; i < text_length; i++) { |
| // Convert ASCII to big-endian UTF-16. |
| dataStruct->write8(0); |
| dataStruct->write8(text[i]); |
| } |
| |
| return dataStruct; |
| } |
| |
| sp<DataStruct> IccHelper::write_xyz_tag(float x, float y, float z) { |
| uint32_t data[] = { |
| Endian_SwapBE32(kXYZ_PCSSpace), |
| 0, |
| static_cast<uint32_t>(Endian_SwapBE32(float_round_to_fixed(x))), |
| static_cast<uint32_t>(Endian_SwapBE32(float_round_to_fixed(y))), |
| static_cast<uint32_t>(Endian_SwapBE32(float_round_to_fixed(z))), |
| }; |
| sp<DataStruct> dataStruct = sp<DataStruct>::make(sizeof(data)); |
| dataStruct->write(&data, sizeof(data)); |
| return dataStruct; |
| } |
| |
| sp<DataStruct> IccHelper::write_trc_tag(const int table_entries, const void* table_16) { |
| int total_length = 4 + 4 + 4 + table_entries * 2; |
| total_length = (((total_length + 2) >> 2) << 2); // 4 aligned |
| sp<DataStruct> dataStruct = sp<DataStruct>::make(total_length); |
| dataStruct->write32(Endian_SwapBE32(kTAG_CurveType)); // Type |
| dataStruct->write32(0); // Reserved |
| dataStruct->write32(Endian_SwapBE32(table_entries)); // Value count |
| for (size_t i = 0; i < table_entries; ++i) { |
| uint16_t value = reinterpret_cast<const uint16_t*>(table_16)[i]; |
| dataStruct->write16(value); |
| } |
| return dataStruct; |
| } |
| |
| sp<DataStruct> IccHelper::write_trc_tag(const TransferFunction& fn) { |
| if (fn.a == 1.f && fn.b == 0.f && fn.c == 0.f |
| && fn.d == 0.f && fn.e == 0.f && fn.f == 0.f) { |
| int total_length = 16; |
| sp<DataStruct> dataStruct = new DataStruct(total_length); |
| dataStruct->write32(Endian_SwapBE32(kTAG_ParaCurveType)); // Type |
| dataStruct->write32(0); // Reserved |
| dataStruct->write32(Endian_SwapBE16(kExponential_ParaCurveType)); |
| dataStruct->write32(Endian_SwapBE32(float_round_to_fixed(fn.g))); |
| return dataStruct; |
| } |
| |
| int total_length = 40; |
| sp<DataStruct> dataStruct = new DataStruct(total_length); |
| dataStruct->write32(Endian_SwapBE32(kTAG_ParaCurveType)); // Type |
| dataStruct->write32(0); // Reserved |
| dataStruct->write32(Endian_SwapBE16(kGABCDEF_ParaCurveType)); |
| dataStruct->write32(Endian_SwapBE32(float_round_to_fixed(fn.g))); |
| dataStruct->write32(Endian_SwapBE32(float_round_to_fixed(fn.a))); |
| dataStruct->write32(Endian_SwapBE32(float_round_to_fixed(fn.b))); |
| dataStruct->write32(Endian_SwapBE32(float_round_to_fixed(fn.c))); |
| dataStruct->write32(Endian_SwapBE32(float_round_to_fixed(fn.d))); |
| dataStruct->write32(Endian_SwapBE32(float_round_to_fixed(fn.e))); |
| dataStruct->write32(Endian_SwapBE32(float_round_to_fixed(fn.f))); |
| return dataStruct; |
| } |
| |
| float IccHelper::compute_tone_map_gain(const ultrahdr_transfer_function tf, float L) { |
| if (L <= 0.f) { |
| return 1.f; |
| } |
| if (tf == ULTRAHDR_TF_PQ) { |
| // The PQ transfer function will map to the range [0, 1]. Linearly scale |
| // it up to the range [0, 10,000/203]. We will then tone map that back |
| // down to [0, 1]. |
| constexpr float kInputMaxLuminance = 10000 / 203.f; |
| constexpr float kOutputMaxLuminance = 1.0; |
| L *= kInputMaxLuminance; |
| |
| // Compute the tone map gain which will tone map from 10,000/203 to 1.0. |
| constexpr float kToneMapA = kOutputMaxLuminance / (kInputMaxLuminance * kInputMaxLuminance); |
| constexpr float kToneMapB = 1.f / kOutputMaxLuminance; |
| return kInputMaxLuminance * (1.f + kToneMapA * L) / (1.f + kToneMapB * L); |
| } |
| if (tf == ULTRAHDR_TF_HLG) { |
| // Let Lw be the brightness of the display in nits. |
| constexpr float Lw = 203.f; |
| const float gamma = 1.2f + 0.42f * std::log(Lw / 1000.f) / std::log(10.f); |
| return std::pow(L, gamma - 1.f); |
| } |
| return 1.f; |
| } |
| |
| sp<DataStruct> IccHelper::write_cicp_tag(uint32_t color_primaries, |
| uint32_t transfer_characteristics) { |
| int total_length = 12; // 4 + 4 + 1 + 1 + 1 + 1 |
| sp<DataStruct> dataStruct = sp<DataStruct>::make(total_length); |
| dataStruct->write32(Endian_SwapBE32(kTAG_cicp)); // Type signature |
| dataStruct->write32(0); // Reserved |
| dataStruct->write8(color_primaries); // Color primaries |
| dataStruct->write8(transfer_characteristics); // Transfer characteristics |
| dataStruct->write8(0); // RGB matrix |
| dataStruct->write8(1); // Full range |
| return dataStruct; |
| } |
| |
| void IccHelper::compute_lut_entry(const Matrix3x3& src_to_XYZD50, float rgb[3]) { |
| // Compute the matrices to convert from source to Rec2020, and from Rec2020 to XYZD50. |
| Matrix3x3 src_to_rec2020; |
| const Matrix3x3 rec2020_to_XYZD50 = kRec2020; |
| { |
| Matrix3x3 XYZD50_to_rec2020; |
| Matrix3x3_invert(&rec2020_to_XYZD50, &XYZD50_to_rec2020); |
| src_to_rec2020 = Matrix3x3_concat(&XYZD50_to_rec2020, &src_to_XYZD50); |
| } |
| |
| // Convert the source signal to linear. |
| for (size_t i = 0; i < kNumChannels; ++i) { |
| rgb[i] = pqOetf(rgb[i]); |
| } |
| |
| // Convert source gamut to Rec2020. |
| Matrix3x3_apply(&src_to_rec2020, rgb); |
| |
| // Compute the luminance of the signal. |
| float L = bt2100Luminance({{{rgb[0], rgb[1], rgb[2]}}}); |
| |
| // Compute the tone map gain based on the luminance. |
| float tone_map_gain = compute_tone_map_gain(ULTRAHDR_TF_PQ, L); |
| |
| // Apply the tone map gain. |
| for (size_t i = 0; i < kNumChannels; ++i) { |
| rgb[i] *= tone_map_gain; |
| } |
| |
| // Convert from Rec2020-linear to XYZD50. |
| Matrix3x3_apply(&rec2020_to_XYZD50, rgb); |
| } |
| |
| sp<DataStruct> IccHelper::write_clut(const uint8_t* grid_points, const uint8_t* grid_16) { |
| uint32_t value_count = kNumChannels; |
| for (uint32_t i = 0; i < kNumChannels; ++i) { |
| value_count *= grid_points[i]; |
| } |
| |
| int total_length = 20 + 2 * value_count; |
| total_length = (((total_length + 2) >> 2) << 2); // 4 aligned |
| sp<DataStruct> dataStruct = sp<DataStruct>::make(total_length); |
| |
| for (size_t i = 0; i < 16; ++i) { |
| dataStruct->write8(i < kNumChannels ? grid_points[i] : 0); // Grid size |
| } |
| dataStruct->write8(2); // Grid byte width (always 16-bit) |
| dataStruct->write8(0); // Reserved |
| dataStruct->write8(0); // Reserved |
| dataStruct->write8(0); // Reserved |
| |
| for (uint32_t i = 0; i < value_count; ++i) { |
| uint16_t value = reinterpret_cast<const uint16_t*>(grid_16)[i]; |
| dataStruct->write16(value); |
| } |
| |
| return dataStruct; |
| } |
| |
| sp<DataStruct> IccHelper::write_mAB_or_mBA_tag(uint32_t type, |
| bool has_a_curves, |
| const uint8_t* grid_points, |
| const uint8_t* grid_16) { |
| const size_t b_curves_offset = 32; |
| sp<DataStruct> b_curves_data[kNumChannels]; |
| sp<DataStruct> a_curves_data[kNumChannels]; |
| size_t clut_offset = 0; |
| sp<DataStruct> clut; |
| size_t a_curves_offset = 0; |
| |
| // The "B" curve is required. |
| for (size_t i = 0; i < kNumChannels; ++i) { |
| b_curves_data[i] = write_trc_tag(kLinear_TransFun); |
| } |
| |
| // The "A" curve and CLUT are optional. |
| if (has_a_curves) { |
| clut_offset = b_curves_offset; |
| for (size_t i = 0; i < kNumChannels; ++i) { |
| clut_offset += b_curves_data[i]->getLength(); |
| } |
| clut = write_clut(grid_points, grid_16); |
| |
| a_curves_offset = clut_offset + clut->getLength(); |
| for (size_t i = 0; i < kNumChannels; ++i) { |
| a_curves_data[i] = write_trc_tag(kLinear_TransFun); |
| } |
| } |
| |
| int total_length = b_curves_offset; |
| for (size_t i = 0; i < kNumChannels; ++i) { |
| total_length += b_curves_data[i]->getLength(); |
| } |
| if (has_a_curves) { |
| total_length += clut->getLength(); |
| for (size_t i = 0; i < kNumChannels; ++i) { |
| total_length += a_curves_data[i]->getLength(); |
| } |
| } |
| sp<DataStruct> dataStruct = sp<DataStruct>::make(total_length); |
| dataStruct->write32(Endian_SwapBE32(type)); // Type signature |
| dataStruct->write32(0); // Reserved |
| dataStruct->write8(kNumChannels); // Input channels |
| dataStruct->write8(kNumChannels); // Output channels |
| dataStruct->write16(0); // Reserved |
| dataStruct->write32(Endian_SwapBE32(b_curves_offset)); // B curve offset |
| dataStruct->write32(Endian_SwapBE32(0)); // Matrix offset (ignored) |
| dataStruct->write32(Endian_SwapBE32(0)); // M curve offset (ignored) |
| dataStruct->write32(Endian_SwapBE32(clut_offset)); // CLUT offset |
| dataStruct->write32(Endian_SwapBE32(a_curves_offset)); // A curve offset |
| for (size_t i = 0; i < kNumChannels; ++i) { |
| if (dataStruct->write(b_curves_data[i]->getData(), b_curves_data[i]->getLength())) { |
| return dataStruct; |
| } |
| } |
| if (has_a_curves) { |
| dataStruct->write(clut->getData(), clut->getLength()); |
| for (size_t i = 0; i < kNumChannels; ++i) { |
| dataStruct->write(a_curves_data[i]->getData(), a_curves_data[i]->getLength()); |
| } |
| } |
| return dataStruct; |
| } |
| |
| sp<DataStruct> IccHelper::writeIccProfile(ultrahdr_transfer_function tf, |
| ultrahdr_color_gamut gamut) { |
| ICCHeader header; |
| |
| std::vector<std::pair<uint32_t, sp<DataStruct>>> tags; |
| |
| // Compute profile description tag |
| std::string desc = get_desc_string(tf, gamut); |
| |
| tags.emplace_back(kTAG_desc, write_text_tag(desc.c_str())); |
| |
| Matrix3x3 toXYZD50; |
| switch (gamut) { |
| case ULTRAHDR_COLORGAMUT_BT709: |
| toXYZD50 = kSRGB; |
| break; |
| case ULTRAHDR_COLORGAMUT_P3: |
| toXYZD50 = kDisplayP3; |
| break; |
| case ULTRAHDR_COLORGAMUT_BT2100: |
| toXYZD50 = kRec2020; |
| break; |
| default: |
| // Should not fall here. |
| return nullptr; |
| } |
| |
| // Compute primaries. |
| { |
| tags.emplace_back(kTAG_rXYZ, |
| write_xyz_tag(toXYZD50.vals[0][0], toXYZD50.vals[1][0], toXYZD50.vals[2][0])); |
| tags.emplace_back(kTAG_gXYZ, |
| write_xyz_tag(toXYZD50.vals[0][1], toXYZD50.vals[1][1], toXYZD50.vals[2][1])); |
| tags.emplace_back(kTAG_bXYZ, |
| write_xyz_tag(toXYZD50.vals[0][2], toXYZD50.vals[1][2], toXYZD50.vals[2][2])); |
| } |
| |
| // Compute white point tag (must be D50) |
| tags.emplace_back(kTAG_wtpt, write_xyz_tag(kD50_x, kD50_y, kD50_z)); |
| |
| // Compute transfer curves. |
| if (tf != ULTRAHDR_TF_PQ) { |
| if (tf == ULTRAHDR_TF_HLG) { |
| std::vector<uint8_t> trc_table; |
| trc_table.resize(kTrcTableSize * 2); |
| for (uint32_t i = 0; i < kTrcTableSize; ++i) { |
| float x = i / (kTrcTableSize - 1.f); |
| float y = hlgOetf(x); |
| y *= compute_tone_map_gain(tf, y); |
| float_to_table16(y, &trc_table[2 * i]); |
| } |
| |
| tags.emplace_back(kTAG_rTRC, |
| write_trc_tag(kTrcTableSize, reinterpret_cast<uint8_t*>(trc_table.data()))); |
| tags.emplace_back(kTAG_gTRC, |
| write_trc_tag(kTrcTableSize, reinterpret_cast<uint8_t*>(trc_table.data()))); |
| tags.emplace_back(kTAG_bTRC, |
| write_trc_tag(kTrcTableSize, reinterpret_cast<uint8_t*>(trc_table.data()))); |
| } else { |
| tags.emplace_back(kTAG_rTRC, write_trc_tag(kSRGB_TransFun)); |
| tags.emplace_back(kTAG_gTRC, write_trc_tag(kSRGB_TransFun)); |
| tags.emplace_back(kTAG_bTRC, write_trc_tag(kSRGB_TransFun)); |
| } |
| } |
| |
| // Compute CICP. |
| if (tf == ULTRAHDR_TF_HLG || tf == ULTRAHDR_TF_PQ) { |
| // The CICP tag is present in ICC 4.4, so update the header's version. |
| header.version = Endian_SwapBE32(0x04400000); |
| |
| uint32_t color_primaries = 0; |
| if (gamut == ULTRAHDR_COLORGAMUT_BT709) { |
| color_primaries = kCICPPrimariesSRGB; |
| } else if (gamut == ULTRAHDR_COLORGAMUT_P3) { |
| color_primaries = kCICPPrimariesP3; |
| } |
| |
| uint32_t transfer_characteristics = 0; |
| if (tf == ULTRAHDR_TF_SRGB) { |
| transfer_characteristics = kCICPTrfnSRGB; |
| } else if (tf == ULTRAHDR_TF_LINEAR) { |
| transfer_characteristics = kCICPTrfnLinear; |
| } else if (tf == ULTRAHDR_TF_PQ) { |
| transfer_characteristics = kCICPTrfnPQ; |
| } else if (tf == ULTRAHDR_TF_HLG) { |
| transfer_characteristics = kCICPTrfnHLG; |
| } |
| tags.emplace_back(kTAG_cicp, write_cicp_tag(color_primaries, transfer_characteristics)); |
| } |
| |
| // Compute A2B0. |
| if (tf == ULTRAHDR_TF_PQ) { |
| std::vector<uint8_t> a2b_grid; |
| a2b_grid.resize(kGridSize * kGridSize * kGridSize * kNumChannels * 2); |
| size_t a2b_grid_index = 0; |
| for (uint32_t r_index = 0; r_index < kGridSize; ++r_index) { |
| for (uint32_t g_index = 0; g_index < kGridSize; ++g_index) { |
| for (uint32_t b_index = 0; b_index < kGridSize; ++b_index) { |
| float rgb[3] = { |
| r_index / (kGridSize - 1.f), |
| g_index / (kGridSize - 1.f), |
| b_index / (kGridSize - 1.f), |
| }; |
| compute_lut_entry(toXYZD50, rgb); |
| float_XYZD50_to_grid16_lab(rgb, &a2b_grid[a2b_grid_index]); |
| a2b_grid_index += 6; |
| } |
| } |
| } |
| const uint8_t* grid_16 = reinterpret_cast<const uint8_t*>(a2b_grid.data()); |
| |
| uint8_t grid_points[kNumChannels]; |
| for (size_t i = 0; i < kNumChannels; ++i) { |
| grid_points[i] = kGridSize; |
| } |
| |
| auto a2b_data = write_mAB_or_mBA_tag(kTAG_mABType, |
| /* has_a_curves */ true, |
| grid_points, |
| grid_16); |
| tags.emplace_back(kTAG_A2B0, std::move(a2b_data)); |
| } |
| |
| // Compute B2A0. |
| if (tf == ULTRAHDR_TF_PQ) { |
| auto b2a_data = write_mAB_or_mBA_tag(kTAG_mBAType, |
| /* has_a_curves */ false, |
| /* grid_points */ nullptr, |
| /* grid_16 */ nullptr); |
| tags.emplace_back(kTAG_B2A0, std::move(b2a_data)); |
| } |
| |
| // Compute copyright tag |
| tags.emplace_back(kTAG_cprt, write_text_tag("Google Inc. 2022")); |
| |
| // Compute the size of the profile. |
| size_t tag_data_size = 0; |
| for (const auto& tag : tags) { |
| tag_data_size += tag.second->getLength(); |
| } |
| size_t tag_table_size = kICCTagTableEntrySize * tags.size(); |
| size_t profile_size = kICCHeaderSize + tag_table_size + tag_data_size; |
| |
| sp<DataStruct> dataStruct = sp<DataStruct>::make(profile_size + kICCIdentifierSize); |
| |
| // Write identifier, chunk count, and chunk ID |
| if (!dataStruct->write(kICCIdentifier, sizeof(kICCIdentifier)) || |
| !dataStruct->write8(1) || !dataStruct->write8(1)) { |
| ALOGE("writeIccProfile(): error in identifier"); |
| return dataStruct; |
| } |
| |
| // Write the header. |
| header.data_color_space = Endian_SwapBE32(Signature_RGB); |
| header.pcs = Endian_SwapBE32(tf == ULTRAHDR_TF_PQ ? Signature_Lab : Signature_XYZ); |
| header.size = Endian_SwapBE32(profile_size); |
| header.tag_count = Endian_SwapBE32(tags.size()); |
| |
| if (!dataStruct->write(&header, sizeof(header))) { |
| ALOGE("writeIccProfile(): error in header"); |
| return dataStruct; |
| } |
| |
| // Write the tag table. Track the offset and size of the previous tag to |
| // compute each tag's offset. An empty SkData indicates that the previous |
| // tag is to be reused. |
| uint32_t last_tag_offset = sizeof(header) + tag_table_size; |
| uint32_t last_tag_size = 0; |
| for (const auto& tag : tags) { |
| last_tag_offset = last_tag_offset + last_tag_size; |
| last_tag_size = tag.second->getLength(); |
| uint32_t tag_table_entry[3] = { |
| Endian_SwapBE32(tag.first), |
| Endian_SwapBE32(last_tag_offset), |
| Endian_SwapBE32(last_tag_size), |
| }; |
| if (!dataStruct->write(tag_table_entry, sizeof(tag_table_entry))) { |
| ALOGE("writeIccProfile(): error in writing tag table"); |
| return dataStruct; |
| } |
| } |
| |
| // Write the tags. |
| for (const auto& tag : tags) { |
| if (!dataStruct->write(tag.second->getData(), tag.second->getLength())) { |
| ALOGE("writeIccProfile(): error in writing tags"); |
| return dataStruct; |
| } |
| } |
| |
| return dataStruct; |
| } |
| |
| bool IccHelper::tagsEqualToMatrix(const Matrix3x3& matrix, |
| const uint8_t* red_tag, |
| const uint8_t* green_tag, |
| const uint8_t* blue_tag) { |
| sp<DataStruct> red_tag_test = write_xyz_tag(matrix.vals[0][0], matrix.vals[1][0], |
| matrix.vals[2][0]); |
| sp<DataStruct> green_tag_test = write_xyz_tag(matrix.vals[0][1], matrix.vals[1][1], |
| matrix.vals[2][1]); |
| sp<DataStruct> blue_tag_test = write_xyz_tag(matrix.vals[0][2], matrix.vals[1][2], |
| matrix.vals[2][2]); |
| return memcmp(red_tag, red_tag_test->getData(), kColorantTagSize) == 0 && |
| memcmp(green_tag, green_tag_test->getData(), kColorantTagSize) == 0 && |
| memcmp(blue_tag, blue_tag_test->getData(), kColorantTagSize) == 0; |
| } |
| |
| ultrahdr_color_gamut IccHelper::readIccColorGamut(void* icc_data, size_t icc_size) { |
| // Each tag table entry consists of 3 fields of 4 bytes each. |
| static const size_t kTagTableEntrySize = 12; |
| |
| if (icc_data == nullptr || icc_size < sizeof(ICCHeader) + kICCIdentifierSize) { |
| return ULTRAHDR_COLORGAMUT_UNSPECIFIED; |
| } |
| |
| if (memcmp(icc_data, kICCIdentifier, sizeof(kICCIdentifier)) != 0) { |
| return ULTRAHDR_COLORGAMUT_UNSPECIFIED; |
| } |
| |
| uint8_t* icc_bytes = reinterpret_cast<uint8_t*>(icc_data) + kICCIdentifierSize; |
| |
| ICCHeader* header = reinterpret_cast<ICCHeader*>(icc_bytes); |
| |
| // Use 0 to indicate not found, since offsets are always relative to start |
| // of ICC data and therefore a tag offset of zero would never be valid. |
| size_t red_primary_offset = 0, green_primary_offset = 0, blue_primary_offset = 0; |
| size_t red_primary_size = 0, green_primary_size = 0, blue_primary_size = 0; |
| for (size_t tag_idx = 0; tag_idx < Endian_SwapBE32(header->tag_count); ++tag_idx) { |
| uint32_t* tag_entry_start = reinterpret_cast<uint32_t*>( |
| icc_bytes + sizeof(ICCHeader) + tag_idx * kTagTableEntrySize); |
| // first 4 bytes are the tag signature, next 4 bytes are the tag offset, |
| // last 4 bytes are the tag length in bytes. |
| if (red_primary_offset == 0 && *tag_entry_start == Endian_SwapBE32(kTAG_rXYZ)) { |
| red_primary_offset = Endian_SwapBE32(*(tag_entry_start+1)); |
| red_primary_size = Endian_SwapBE32(*(tag_entry_start+2)); |
| } else if (green_primary_offset == 0 && *tag_entry_start == Endian_SwapBE32(kTAG_gXYZ)) { |
| green_primary_offset = Endian_SwapBE32(*(tag_entry_start+1)); |
| green_primary_size = Endian_SwapBE32(*(tag_entry_start+2)); |
| } else if (blue_primary_offset == 0 && *tag_entry_start == Endian_SwapBE32(kTAG_bXYZ)) { |
| blue_primary_offset = Endian_SwapBE32(*(tag_entry_start+1)); |
| blue_primary_size = Endian_SwapBE32(*(tag_entry_start+2)); |
| } |
| } |
| |
| if (red_primary_offset == 0 || red_primary_size != kColorantTagSize || |
| kICCIdentifierSize + red_primary_offset + red_primary_size > icc_size || |
| green_primary_offset == 0 || green_primary_size != kColorantTagSize || |
| kICCIdentifierSize + green_primary_offset + green_primary_size > icc_size || |
| blue_primary_offset == 0 || blue_primary_size != kColorantTagSize || |
| kICCIdentifierSize + blue_primary_offset + blue_primary_size > icc_size) { |
| return ULTRAHDR_COLORGAMUT_UNSPECIFIED; |
| } |
| |
| uint8_t* red_tag = icc_bytes + red_primary_offset; |
| uint8_t* green_tag = icc_bytes + green_primary_offset; |
| uint8_t* blue_tag = icc_bytes + blue_primary_offset; |
| |
| // Serialize tags as we do on encode and compare what we find to that to |
| // determine the gamut (since we don't have a need yet for full deserialize). |
| if (tagsEqualToMatrix(kSRGB, red_tag, green_tag, blue_tag)) { |
| return ULTRAHDR_COLORGAMUT_BT709; |
| } else if (tagsEqualToMatrix(kDisplayP3, red_tag, green_tag, blue_tag)) { |
| return ULTRAHDR_COLORGAMUT_P3; |
| } else if (tagsEqualToMatrix(kRec2020, red_tag, green_tag, blue_tag)) { |
| return ULTRAHDR_COLORGAMUT_BT2100; |
| } |
| |
| // Didn't find a match to one of the profiles we write; indicate the gamut |
| // is unspecified since we don't understand it. |
| return ULTRAHDR_COLORGAMUT_UNSPECIFIED; |
| } |
| |
| } // namespace android::ultrahdr |
