1 /*
2 * Copyright 2022 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #ifndef ULTRAHDR_ICC_H
18 #define ULTRAHDR_ICC_H
19
20 #include <memory>
21
22 #ifndef USE_BIG_ENDIAN_IN_ICC
23 #define USE_BIG_ENDIAN_IN_ICC true
24 #endif
25
26 #undef Endian_SwapBE32
27 #undef Endian_SwapBE16
28 #if USE_BIG_ENDIAN_IN_ICC
29 #define Endian_SwapBE32(n) EndianSwap32(n)
30 #define Endian_SwapBE16(n) EndianSwap16(n)
31 #else
32 #define Endian_SwapBE32(n) (n)
33 #define Endian_SwapBE16(n) (n)
34 #endif
35
36 #include "ultrahdr/ultrahdr.h"
37 #include "ultrahdr/jpegr.h"
38 #include "ultrahdr/gainmapmath.h"
39 #include "ultrahdr/jpegrutils.h"
40
41 namespace ultrahdr {
42
43 typedef int32_t Fixed;
44 #define Fixed1 (1 << 16)
45 #define MaxS32FitsInFloat 2147483520
46 #define MinS32FitsInFloat (-MaxS32FitsInFloat)
47 #define FixedToFloat(x) ((x)*1.52587890625e-5f)
48
49 typedef struct Matrix3x3 {
50 float vals[3][3];
51 } Matrix3x3;
52
53 // The D50 illuminant.
54 constexpr float kD50_x = 0.9642f;
55 constexpr float kD50_y = 1.0000f;
56 constexpr float kD50_z = 0.8249f;
57
58 enum {
59 // data_color_space
60 Signature_CMYK = 0x434D594B,
61 Signature_Gray = 0x47524159,
62 Signature_RGB = 0x52474220,
63
64 // pcs
65 Signature_Lab = 0x4C616220,
66 Signature_XYZ = 0x58595A20,
67 };
68
69 typedef uint32_t FourByteTag;
SetFourByteTag(char a,char b,char c,char d)70 static inline constexpr FourByteTag SetFourByteTag(char a, char b, char c, char d) {
71 return (((uint32_t)a << 24) | ((uint32_t)b << 16) | ((uint32_t)c << 8) | (uint32_t)d);
72 }
73
74 static constexpr char kICCIdentifier[] = "ICC_PROFILE";
75 // 12 for the actual identifier, +2 for the chunk count and chunk index which
76 // will always follow.
77 static constexpr size_t kICCIdentifierSize = 14;
78
79 // This is equal to the header size according to the ICC specification (128)
80 // plus the size of the tag count (4). We include the tag count since we
81 // always require it to be present anyway.
82 static constexpr size_t kICCHeaderSize = 132;
83
84 // Contains a signature (4), offset (4), and size (4).
85 static constexpr size_t kICCTagTableEntrySize = 12;
86
87 // size should be 20; 4 bytes for type descriptor, 4 bytes reserved, 12
88 // bytes for a single XYZ number type (4 bytes per coordinate).
89 static constexpr size_t kColorantTagSize = 20;
90
91 static constexpr uint32_t kDisplay_Profile = SetFourByteTag('m', 'n', 't', 'r');
92 static constexpr uint32_t kRGB_ColorSpace = SetFourByteTag('R', 'G', 'B', ' ');
93 static constexpr uint32_t kXYZ_PCSSpace = SetFourByteTag('X', 'Y', 'Z', ' ');
94 static constexpr uint32_t kACSP_Signature = SetFourByteTag('a', 'c', 's', 'p');
95
96 static constexpr uint32_t kTAG_desc = SetFourByteTag('d', 'e', 's', 'c');
97 static constexpr uint32_t kTAG_TextType = SetFourByteTag('m', 'l', 'u', 'c');
98 static constexpr uint32_t kTAG_rXYZ = SetFourByteTag('r', 'X', 'Y', 'Z');
99 static constexpr uint32_t kTAG_gXYZ = SetFourByteTag('g', 'X', 'Y', 'Z');
100 static constexpr uint32_t kTAG_bXYZ = SetFourByteTag('b', 'X', 'Y', 'Z');
101 static constexpr uint32_t kTAG_wtpt = SetFourByteTag('w', 't', 'p', 't');
102 static constexpr uint32_t kTAG_rTRC = SetFourByteTag('r', 'T', 'R', 'C');
103 static constexpr uint32_t kTAG_gTRC = SetFourByteTag('g', 'T', 'R', 'C');
104 static constexpr uint32_t kTAG_bTRC = SetFourByteTag('b', 'T', 'R', 'C');
105 static constexpr uint32_t kTAG_cicp = SetFourByteTag('c', 'i', 'c', 'p');
106 static constexpr uint32_t kTAG_cprt = SetFourByteTag('c', 'p', 'r', 't');
107 static constexpr uint32_t kTAG_A2B0 = SetFourByteTag('A', '2', 'B', '0');
108 static constexpr uint32_t kTAG_B2A0 = SetFourByteTag('B', '2', 'A', '0');
109
110 static constexpr uint32_t kTAG_CurveType = SetFourByteTag('c', 'u', 'r', 'v');
111 static constexpr uint32_t kTAG_mABType = SetFourByteTag('m', 'A', 'B', ' ');
112 static constexpr uint32_t kTAG_mBAType = SetFourByteTag('m', 'B', 'A', ' ');
113 static constexpr uint32_t kTAG_ParaCurveType = SetFourByteTag('p', 'a', 'r', 'a');
114
115 static constexpr Matrix3x3 kSRGB = {{
116 // ICC fixed-point (16.16) representation, taken from skcms. Please keep them exactly in sync.
117 // 0.436065674f, 0.385147095f, 0.143066406f,
118 // 0.222488403f, 0.716873169f, 0.060607910f,
119 // 0.013916016f, 0.097076416f, 0.714096069f,
120 {FixedToFloat(0x6FA2), FixedToFloat(0x6299), FixedToFloat(0x24A0)},
121 {FixedToFloat(0x38F5), FixedToFloat(0xB785), FixedToFloat(0x0F84)},
122 {FixedToFloat(0x0390), FixedToFloat(0x18DA), FixedToFloat(0xB6CF)},
123 }};
124
125 static constexpr Matrix3x3 kDisplayP3 = {{
126 {0.515102f, 0.291965f, 0.157153f},
127 {0.241182f, 0.692236f, 0.0665819f},
128 {-0.00104941f, 0.0418818f, 0.784378f},
129 }};
130
131 static constexpr Matrix3x3 kRec2020 = {{
132 {0.673459f, 0.165661f, 0.125100f},
133 {0.279033f, 0.675338f, 0.0456288f},
134 {-0.00193139f, 0.0299794f, 0.797162f},
135 }};
136
137 static constexpr uint32_t kCICPPrimariesSRGB = 1;
138 static constexpr uint32_t kCICPPrimariesP3 = 12;
139 static constexpr uint32_t kCICPPrimariesRec2020 = 9;
140
141 static constexpr uint32_t kCICPTrfnSRGB = 1;
142 static constexpr uint32_t kCICPTrfnLinear = 8;
143 static constexpr uint32_t kCICPTrfnPQ = 16;
144 static constexpr uint32_t kCICPTrfnHLG = 18;
145
146 enum ParaCurveType {
147 kExponential_ParaCurveType = 0,
148 kGAB_ParaCurveType = 1,
149 kGABC_ParaCurveType = 2,
150 kGABDE_ParaCurveType = 3,
151 kGABCDEF_ParaCurveType = 4,
152 };
153
154 /**
155 * Return the closest int for the given float. Returns MaxS32FitsInFloat for NaN.
156 */
float_saturate2int(float x)157 static inline int float_saturate2int(float x) {
158 x = x < MaxS32FitsInFloat ? x : MaxS32FitsInFloat;
159 x = x > MinS32FitsInFloat ? x : MinS32FitsInFloat;
160 return (int)x;
161 }
162
float_round_to_fixed(float x)163 static inline Fixed float_round_to_fixed(float x) {
164 return float_saturate2int((float)floor((double)x * Fixed1 + 0.5));
165 }
166
float_round_to_unorm16(float x)167 static uint16_t float_round_to_unorm16(float x) {
168 x = x * 65535.f + 0.5;
169 if (x > 65535) return 65535;
170 if (x < 0) return 0;
171 return static_cast<uint16_t>(x);
172 }
173
float_to_table16(const float f,uint8_t * table_16)174 static inline void float_to_table16(const float f, uint8_t* table_16) {
175 *reinterpret_cast<uint16_t*>(table_16) = Endian_SwapBE16(float_round_to_unorm16(f));
176 }
177
isfinitef_(float x)178 static inline bool isfinitef_(float x) { return 0 == x * 0; }
179
180 struct ICCHeader {
181 // Size of the profile (computed)
182 uint32_t size;
183 // Preferred CMM type (ignored)
184 uint32_t cmm_type = 0;
185 // Version 4.3 or 4.4 if CICP is included.
186 uint32_t version = Endian_SwapBE32(0x04300000);
187 // Display device profile
188 uint32_t profile_class = Endian_SwapBE32(kDisplay_Profile);
189 // RGB input color space;
190 uint32_t data_color_space = Endian_SwapBE32(kRGB_ColorSpace);
191 // Profile connection space.
192 uint32_t pcs = Endian_SwapBE32(kXYZ_PCSSpace);
193 // Date and time (ignored)
194 uint8_t creation_date_time[12] = {0};
195 // Profile signature
196 uint32_t signature = Endian_SwapBE32(kACSP_Signature);
197 // Platform target (ignored)
198 uint32_t platform = 0;
199 // Flags: not embedded, can be used independently
200 uint32_t flags = 0x00000000;
201 // Device manufacturer (ignored)
202 uint32_t device_manufacturer = 0;
203 // Device model (ignored)
204 uint32_t device_model = 0;
205 // Device attributes (ignored)
206 uint8_t device_attributes[8] = {0};
207 // Relative colorimetric rendering intent
208 uint32_t rendering_intent = Endian_SwapBE32(1);
209 // D50 standard illuminant (X, Y, Z)
210 uint32_t illuminant_X = Endian_SwapBE32(float_round_to_fixed(kD50_x));
211 uint32_t illuminant_Y = Endian_SwapBE32(float_round_to_fixed(kD50_y));
212 uint32_t illuminant_Z = Endian_SwapBE32(float_round_to_fixed(kD50_z));
213 // Profile creator (ignored)
214 uint32_t creator = 0;
215 // Profile id checksum (ignored)
216 uint8_t profile_id[16] = {0};
217 // Reserved (ignored)
218 uint8_t reserved[28] = {0};
219 // Technically not part of header, but required
220 uint32_t tag_count = 0;
221 };
222
223 class IccHelper {
224 private:
225 static constexpr uint32_t kTrcTableSize = 65;
226 static constexpr uint32_t kGridSize = 17;
227 static constexpr size_t kNumChannels = 3;
228
229 static std::shared_ptr<DataStruct> write_text_tag(const char* text);
230 static std::string get_desc_string(const ultrahdr_transfer_function tf,
231 const ultrahdr_color_gamut gamut);
232 static std::shared_ptr<DataStruct> write_xyz_tag(float x, float y, float z);
233 static std::shared_ptr<DataStruct> write_trc_tag(const int table_entries, const void* table_16);
234 static std::shared_ptr<DataStruct> write_trc_tag(const TransferFunction& fn);
235 static float compute_tone_map_gain(const ultrahdr_transfer_function tf, float L);
236 static std::shared_ptr<DataStruct> write_cicp_tag(uint32_t color_primaries,
237 uint32_t transfer_characteristics);
238 static std::shared_ptr<DataStruct> write_mAB_or_mBA_tag(uint32_t type, bool has_a_curves,
239 const uint8_t* grid_points,
240 const uint8_t* grid_16);
241 static void compute_lut_entry(const Matrix3x3& src_to_XYZD50, float rgb[3]);
242 static std::shared_ptr<DataStruct> write_clut(const uint8_t* grid_points, const uint8_t* grid_16);
243
244 // Checks if a set of xyz tags is equivalent to a 3x3 Matrix. Each input
245 // tag buffer assumed to be at least kColorantTagSize in size.
246 static bool tagsEqualToMatrix(const Matrix3x3& matrix, const uint8_t* red_tag,
247 const uint8_t* green_tag, const uint8_t* blue_tag);
248
249 public:
250 // Output includes JPEG embedding identifier and chunk information, but not
251 // APPx information.
252 static std::shared_ptr<DataStruct> writeIccProfile(const ultrahdr_transfer_function tf,
253 const ultrahdr_color_gamut gamut);
254 // NOTE: this function is not robust; it can infer gamuts that IccHelper
255 // writes out but should not be considered a reference implementation for
256 // robust parsing of ICC profiles or their gamuts.
257 static ultrahdr_color_gamut readIccColorGamut(void* icc_data, size_t icc_size);
258 };
259 } // namespace ultrahdr
260
261 #endif // ULTRAHDR_ICC_H
262