1 //---------------------------------------------------------------------------------
2 //
3 // Little Color Management System
4 // Copyright (c) 1998-2012 Marti Maria Saguer
5 //
6 // Permission is hereby granted, free of charge, to any person obtaining
7 // a copy of this software and associated documentation files (the "Software"),
8 // to deal in the Software without restriction, including without limitation
9 // the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 // and/or sell copies of the Software, and to permit persons to whom the Software
11 // is furnished to do so, subject to the following conditions:
12 //
13 // The above copyright notice and this permission notice shall be included in
14 // all copies or substantial portions of the Software.
15 //
16 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
17 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO
18 // THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
19 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
20 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
21 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
22 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
23 //
24 //---------------------------------------------------------------------------------
25 //
26
27 #include "lcms2_internal.h"
28
29 // CIECAM 02 appearance model. Many thanks to Jordi Vilar for the debugging.
30
31 // ---------- Implementation --------------------------------------------
32
33 typedef struct {
34
35 cmsFloat64Number XYZ[3];
36 cmsFloat64Number RGB[3];
37 cmsFloat64Number RGBc[3];
38 cmsFloat64Number RGBp[3];
39 cmsFloat64Number RGBpa[3];
40 cmsFloat64Number a, b, h, e, H, A, J, Q, s, t, C, M;
41 cmsFloat64Number abC[2];
42 cmsFloat64Number abs[2];
43 cmsFloat64Number abM[2];
44
45 } CAM02COLOR;
46
47 typedef struct {
48
49 CAM02COLOR adoptedWhite;
50 cmsFloat64Number LA, Yb;
51 cmsFloat64Number F, c, Nc;
52 cmsUInt32Number surround;
53 cmsFloat64Number n, Nbb, Ncb, z, FL, D;
54
55 cmsContext ContextID;
56
57 } cmsCIECAM02;
58
59
60 static
compute_n(cmsCIECAM02 * pMod)61 cmsFloat64Number compute_n(cmsCIECAM02* pMod)
62 {
63 return (pMod -> Yb / pMod -> adoptedWhite.XYZ[1]);
64 }
65
66 static
compute_z(cmsCIECAM02 * pMod)67 cmsFloat64Number compute_z(cmsCIECAM02* pMod)
68 {
69 return (1.48 + pow(pMod -> n, 0.5));
70 }
71
72 static
computeNbb(cmsCIECAM02 * pMod)73 cmsFloat64Number computeNbb(cmsCIECAM02* pMod)
74 {
75 return (0.725 * pow((1.0 / pMod -> n), 0.2));
76 }
77
78 static
computeFL(cmsCIECAM02 * pMod)79 cmsFloat64Number computeFL(cmsCIECAM02* pMod)
80 {
81 cmsFloat64Number k, FL;
82
83 k = 1.0 / ((5.0 * pMod->LA) + 1.0);
84 FL = 0.2 * pow(k, 4.0) * (5.0 * pMod->LA) + 0.1 *
85 (pow((1.0 - pow(k, 4.0)), 2.0)) *
86 (pow((5.0 * pMod->LA), (1.0 / 3.0)));
87
88 return FL;
89 }
90
91 static
computeD(cmsCIECAM02 * pMod)92 cmsFloat64Number computeD(cmsCIECAM02* pMod)
93 {
94 cmsFloat64Number D;
95
96 D = pMod->F - (1.0/3.6)*(exp(((-pMod ->LA-42) / 92.0)));
97
98 return D;
99 }
100
101
102 static
XYZtoCAT02(CAM02COLOR clr)103 CAM02COLOR XYZtoCAT02(CAM02COLOR clr)
104 {
105 clr.RGB[0] = (clr.XYZ[0] * 0.7328) + (clr.XYZ[1] * 0.4296) + (clr.XYZ[2] * -0.1624);
106 clr.RGB[1] = (clr.XYZ[0] * -0.7036) + (clr.XYZ[1] * 1.6975) + (clr.XYZ[2] * 0.0061);
107 clr.RGB[2] = (clr.XYZ[0] * 0.0030) + (clr.XYZ[1] * 0.0136) + (clr.XYZ[2] * 0.9834);
108
109 return clr;
110 }
111
112 static
ChromaticAdaptation(CAM02COLOR clr,cmsCIECAM02 * pMod)113 CAM02COLOR ChromaticAdaptation(CAM02COLOR clr, cmsCIECAM02* pMod)
114 {
115 cmsUInt32Number i;
116
117 for (i = 0; i < 3; i++) {
118 clr.RGBc[i] = ((pMod -> adoptedWhite.XYZ[1] *
119 (pMod->D / pMod -> adoptedWhite.RGB[i])) +
120 (1.0 - pMod->D)) * clr.RGB[i];
121 }
122
123 return clr;
124 }
125
126
127 static
CAT02toHPE(CAM02COLOR clr)128 CAM02COLOR CAT02toHPE(CAM02COLOR clr)
129 {
130 cmsFloat64Number M[9];
131
132 M[0] =(( 0.38971 * 1.096124) + (0.68898 * 0.454369) + (-0.07868 * -0.009628));
133 M[1] =(( 0.38971 * -0.278869) + (0.68898 * 0.473533) + (-0.07868 * -0.005698));
134 M[2] =(( 0.38971 * 0.182745) + (0.68898 * 0.072098) + (-0.07868 * 1.015326));
135 M[3] =((-0.22981 * 1.096124) + (1.18340 * 0.454369) + ( 0.04641 * -0.009628));
136 M[4] =((-0.22981 * -0.278869) + (1.18340 * 0.473533) + ( 0.04641 * -0.005698));
137 M[5] =((-0.22981 * 0.182745) + (1.18340 * 0.072098) + ( 0.04641 * 1.015326));
138 M[6] =(-0.009628);
139 M[7] =(-0.005698);
140 M[8] =( 1.015326);
141
142 clr.RGBp[0] = (clr.RGBc[0] * M[0]) + (clr.RGBc[1] * M[1]) + (clr.RGBc[2] * M[2]);
143 clr.RGBp[1] = (clr.RGBc[0] * M[3]) + (clr.RGBc[1] * M[4]) + (clr.RGBc[2] * M[5]);
144 clr.RGBp[2] = (clr.RGBc[0] * M[6]) + (clr.RGBc[1] * M[7]) + (clr.RGBc[2] * M[8]);
145
146 return clr;
147 }
148
149 static
NonlinearCompression(CAM02COLOR clr,cmsCIECAM02 * pMod)150 CAM02COLOR NonlinearCompression(CAM02COLOR clr, cmsCIECAM02* pMod)
151 {
152 cmsUInt32Number i;
153 cmsFloat64Number temp;
154
155 for (i = 0; i < 3; i++) {
156 if (clr.RGBp[i] < 0) {
157
158 temp = pow((-1.0 * pMod->FL * clr.RGBp[i] / 100.0), 0.42);
159 clr.RGBpa[i] = (-1.0 * 400.0 * temp) / (temp + 27.13) + 0.1;
160 }
161 else {
162 temp = pow((pMod->FL * clr.RGBp[i] / 100.0), 0.42);
163 clr.RGBpa[i] = (400.0 * temp) / (temp + 27.13) + 0.1;
164 }
165 }
166
167 clr.A = (((2.0 * clr.RGBpa[0]) + clr.RGBpa[1] +
168 (clr.RGBpa[2] / 20.0)) - 0.305) * pMod->Nbb;
169
170 return clr;
171 }
172
173 static
ComputeCorrelates(CAM02COLOR clr,cmsCIECAM02 * pMod)174 CAM02COLOR ComputeCorrelates(CAM02COLOR clr, cmsCIECAM02* pMod)
175 {
176 cmsFloat64Number a, b, temp, e, t, r2d, d2r;
177
178 a = clr.RGBpa[0] - (12.0 * clr.RGBpa[1] / 11.0) + (clr.RGBpa[2] / 11.0);
179 b = (clr.RGBpa[0] + clr.RGBpa[1] - (2.0 * clr.RGBpa[2])) / 9.0;
180
181 r2d = (180.0 / 3.141592654);
182 if (a == 0) {
183 if (b == 0) clr.h = 0;
184 else if (b > 0) clr.h = 90;
185 else clr.h = 270;
186 }
187 else if (a > 0) {
188 temp = b / a;
189 if (b > 0) clr.h = (r2d * atan(temp));
190 else if (b == 0) clr.h = 0;
191 else clr.h = (r2d * atan(temp)) + 360;
192 }
193 else {
194 temp = b / a;
195 clr.h = (r2d * atan(temp)) + 180;
196 }
197
198 d2r = (3.141592654 / 180.0);
199 e = ((12500.0 / 13.0) * pMod->Nc * pMod->Ncb) *
200 (cos((clr.h * d2r + 2.0)) + 3.8);
201
202 if (clr.h < 20.14) {
203 temp = ((clr.h + 122.47)/1.2) + ((20.14 - clr.h)/0.8);
204 clr.H = 300 + (100*((clr.h + 122.47)/1.2)) / temp;
205 }
206 else if (clr.h < 90.0) {
207 temp = ((clr.h - 20.14)/0.8) + ((90.00 - clr.h)/0.7);
208 clr.H = (100*((clr.h - 20.14)/0.8)) / temp;
209 }
210 else if (clr.h < 164.25) {
211 temp = ((clr.h - 90.00)/0.7) + ((164.25 - clr.h)/1.0);
212 clr.H = 100 + ((100*((clr.h - 90.00)/0.7)) / temp);
213 }
214 else if (clr.h < 237.53) {
215 temp = ((clr.h - 164.25)/1.0) + ((237.53 - clr.h)/1.2);
216 clr.H = 200 + ((100*((clr.h - 164.25)/1.0)) / temp);
217 }
218 else {
219 temp = ((clr.h - 237.53)/1.2) + ((360 - clr.h + 20.14)/0.8);
220 clr.H = 300 + ((100*((clr.h - 237.53)/1.2)) / temp);
221 }
222
223 clr.J = 100.0 * pow((clr.A / pMod->adoptedWhite.A),
224 (pMod->c * pMod->z));
225
226 clr.Q = (4.0 / pMod->c) * pow((clr.J / 100.0), 0.5) *
227 (pMod->adoptedWhite.A + 4.0) * pow(pMod->FL, 0.25);
228
229 t = (e * pow(((a * a) + (b * b)), 0.5)) /
230 (clr.RGBpa[0] + clr.RGBpa[1] +
231 ((21.0 / 20.0) * clr.RGBpa[2]));
232
233 clr.C = pow(t, 0.9) * pow((clr.J / 100.0), 0.5) *
234 pow((1.64 - pow(0.29, pMod->n)), 0.73);
235
236 clr.M = clr.C * pow(pMod->FL, 0.25);
237 clr.s = 100.0 * pow((clr.M / clr.Q), 0.5);
238
239 return clr;
240 }
241
242
243 static
InverseCorrelates(CAM02COLOR clr,cmsCIECAM02 * pMod)244 CAM02COLOR InverseCorrelates(CAM02COLOR clr, cmsCIECAM02* pMod)
245 {
246
247 cmsFloat64Number t, e, p1, p2, p3, p4, p5, hr, d2r;
248 d2r = 3.141592654 / 180.0;
249
250 t = pow( (clr.C / (pow((clr.J / 100.0), 0.5) *
251 (pow((1.64 - pow(0.29, pMod->n)), 0.73)))),
252 (1.0 / 0.9) );
253 e = ((12500.0 / 13.0) * pMod->Nc * pMod->Ncb) *
254 (cos((clr.h * d2r + 2.0)) + 3.8);
255
256 clr.A = pMod->adoptedWhite.A * pow(
257 (clr.J / 100.0),
258 (1.0 / (pMod->c * pMod->z)));
259
260 p1 = e / t;
261 p2 = (clr.A / pMod->Nbb) + 0.305;
262 p3 = 21.0 / 20.0;
263
264 hr = clr.h * d2r;
265
266 if (fabs(sin(hr)) >= fabs(cos(hr))) {
267 p4 = p1 / sin(hr);
268 clr.b = (p2 * (2.0 + p3) * (460.0 / 1403.0)) /
269 (p4 + (2.0 + p3) * (220.0 / 1403.0) *
270 (cos(hr) / sin(hr)) - (27.0 / 1403.0) +
271 p3 * (6300.0 / 1403.0));
272 clr.a = clr.b * (cos(hr) / sin(hr));
273 }
274 else {
275 p5 = p1 / cos(hr);
276 clr.a = (p2 * (2.0 + p3) * (460.0 / 1403.0)) /
277 (p5 + (2.0 + p3) * (220.0 / 1403.0) -
278 ((27.0 / 1403.0) - p3 * (6300.0 / 1403.0)) *
279 (sin(hr) / cos(hr)));
280 clr.b = clr.a * (sin(hr) / cos(hr));
281 }
282
283 clr.RGBpa[0] = ((460.0 / 1403.0) * p2) +
284 ((451.0 / 1403.0) * clr.a) +
285 ((288.0 / 1403.0) * clr.b);
286 clr.RGBpa[1] = ((460.0 / 1403.0) * p2) -
287 ((891.0 / 1403.0) * clr.a) -
288 ((261.0 / 1403.0) * clr.b);
289 clr.RGBpa[2] = ((460.0 / 1403.0) * p2) -
290 ((220.0 / 1403.0) * clr.a) -
291 ((6300.0 / 1403.0) * clr.b);
292
293 return clr;
294 }
295
296 static
InverseNonlinearity(CAM02COLOR clr,cmsCIECAM02 * pMod)297 CAM02COLOR InverseNonlinearity(CAM02COLOR clr, cmsCIECAM02* pMod)
298 {
299 cmsUInt32Number i;
300 cmsFloat64Number c1;
301
302 for (i = 0; i < 3; i++) {
303 if ((clr.RGBpa[i] - 0.1) < 0) c1 = -1;
304 else c1 = 1;
305 clr.RGBp[i] = c1 * (100.0 / pMod->FL) *
306 pow(((27.13 * fabs(clr.RGBpa[i] - 0.1)) /
307 (400.0 - fabs(clr.RGBpa[i] - 0.1))),
308 (1.0 / 0.42));
309 }
310
311 return clr;
312 }
313
314 static
HPEtoCAT02(CAM02COLOR clr)315 CAM02COLOR HPEtoCAT02(CAM02COLOR clr)
316 {
317 cmsFloat64Number M[9];
318
319 M[0] = (( 0.7328 * 1.910197) + (0.4296 * 0.370950));
320 M[1] = (( 0.7328 * -1.112124) + (0.4296 * 0.629054));
321 M[2] = (( 0.7328 * 0.201908) + (0.4296 * 0.000008) - 0.1624);
322 M[3] = ((-0.7036 * 1.910197) + (1.6975 * 0.370950));
323 M[4] = ((-0.7036 * -1.112124) + (1.6975 * 0.629054));
324 M[5] = ((-0.7036 * 0.201908) + (1.6975 * 0.000008) + 0.0061);
325 M[6] = (( 0.0030 * 1.910197) + (0.0136 * 0.370950));
326 M[7] = (( 0.0030 * -1.112124) + (0.0136 * 0.629054));
327 M[8] = (( 0.0030 * 0.201908) + (0.0136 * 0.000008) + 0.9834);;
328
329 clr.RGBc[0] = (clr.RGBp[0] * M[0]) + (clr.RGBp[1] * M[1]) + (clr.RGBp[2] * M[2]);
330 clr.RGBc[1] = (clr.RGBp[0] * M[3]) + (clr.RGBp[1] * M[4]) + (clr.RGBp[2] * M[5]);
331 clr.RGBc[2] = (clr.RGBp[0] * M[6]) + (clr.RGBp[1] * M[7]) + (clr.RGBp[2] * M[8]);
332 return clr;
333 }
334
335
336 static
InverseChromaticAdaptation(CAM02COLOR clr,cmsCIECAM02 * pMod)337 CAM02COLOR InverseChromaticAdaptation(CAM02COLOR clr, cmsCIECAM02* pMod)
338 {
339 cmsUInt32Number i;
340 for (i = 0; i < 3; i++) {
341 clr.RGB[i] = clr.RGBc[i] /
342 ((pMod->adoptedWhite.XYZ[1] * pMod->D / pMod->adoptedWhite.RGB[i]) + 1.0 - pMod->D);
343 }
344 return clr;
345 }
346
347
348 static
CAT02toXYZ(CAM02COLOR clr)349 CAM02COLOR CAT02toXYZ(CAM02COLOR clr)
350 {
351 clr.XYZ[0] = (clr.RGB[0] * 1.096124) + (clr.RGB[1] * -0.278869) + (clr.RGB[2] * 0.182745);
352 clr.XYZ[1] = (clr.RGB[0] * 0.454369) + (clr.RGB[1] * 0.473533) + (clr.RGB[2] * 0.072098);
353 clr.XYZ[2] = (clr.RGB[0] * -0.009628) + (clr.RGB[1] * -0.005698) + (clr.RGB[2] * 1.015326);
354
355 return clr;
356 }
357
358
cmsCIECAM02Init(cmsContext ContextID,const cmsViewingConditions * pVC)359 cmsHANDLE CMSEXPORT cmsCIECAM02Init(cmsContext ContextID, const cmsViewingConditions* pVC)
360 {
361 cmsCIECAM02* lpMod;
362
363 _cmsAssert(pVC != NULL);
364
365 if((lpMod = (cmsCIECAM02*) _cmsMallocZero(ContextID, sizeof(cmsCIECAM02))) == NULL) {
366 return NULL;
367 }
368
369 lpMod ->ContextID = ContextID;
370
371 lpMod ->adoptedWhite.XYZ[0] = pVC ->whitePoint.X;
372 lpMod ->adoptedWhite.XYZ[1] = pVC ->whitePoint.Y;
373 lpMod ->adoptedWhite.XYZ[2] = pVC ->whitePoint.Z;
374
375 lpMod -> LA = pVC ->La;
376 lpMod -> Yb = pVC ->Yb;
377 lpMod -> D = pVC ->D_value;
378 lpMod -> surround = pVC ->surround;
379
380 switch (lpMod -> surround) {
381
382
383 case CUTSHEET_SURROUND:
384 lpMod->F = 0.8;
385 lpMod->c = 0.41;
386 lpMod->Nc = 0.8;
387 break;
388
389 case DARK_SURROUND:
390 lpMod -> F = 0.8;
391 lpMod -> c = 0.525;
392 lpMod -> Nc = 0.8;
393 break;
394
395 case DIM_SURROUND:
396 lpMod -> F = 0.9;
397 lpMod -> c = 0.59;
398 lpMod -> Nc = 0.95;
399 break;
400
401 default:
402 // Average surround
403 lpMod -> F = 1.0;
404 lpMod -> c = 0.69;
405 lpMod -> Nc = 1.0;
406 }
407
408 lpMod -> n = compute_n(lpMod);
409 lpMod -> z = compute_z(lpMod);
410 lpMod -> Nbb = computeNbb(lpMod);
411 lpMod -> FL = computeFL(lpMod);
412
413 if (lpMod -> D == D_CALCULATE) {
414 lpMod -> D = computeD(lpMod);
415 }
416
417 lpMod -> Ncb = lpMod -> Nbb;
418
419 lpMod -> adoptedWhite = XYZtoCAT02(lpMod -> adoptedWhite);
420 lpMod -> adoptedWhite = ChromaticAdaptation(lpMod -> adoptedWhite, lpMod);
421 lpMod -> adoptedWhite = CAT02toHPE(lpMod -> adoptedWhite);
422 lpMod -> adoptedWhite = NonlinearCompression(lpMod -> adoptedWhite, lpMod);
423
424 return (cmsHANDLE) lpMod;
425
426 }
427
cmsCIECAM02Done(cmsHANDLE hModel)428 void CMSEXPORT cmsCIECAM02Done(cmsHANDLE hModel)
429 {
430 cmsCIECAM02* lpMod = (cmsCIECAM02*) hModel;
431
432 if (lpMod) _cmsFree(lpMod ->ContextID, lpMod);
433 }
434
435
cmsCIECAM02Forward(cmsHANDLE hModel,const cmsCIEXYZ * pIn,cmsJCh * pOut)436 void CMSEXPORT cmsCIECAM02Forward(cmsHANDLE hModel, const cmsCIEXYZ* pIn, cmsJCh* pOut)
437 {
438 CAM02COLOR clr;
439 cmsCIECAM02* lpMod = (cmsCIECAM02*) hModel;
440
441 _cmsAssert(lpMod != NULL);
442 _cmsAssert(pIn != NULL);
443 _cmsAssert(pOut != NULL);
444
445 memset(&clr, 0, sizeof(clr));
446
447 clr.XYZ[0] = pIn ->X;
448 clr.XYZ[1] = pIn ->Y;
449 clr.XYZ[2] = pIn ->Z;
450
451 clr = XYZtoCAT02(clr);
452 clr = ChromaticAdaptation(clr, lpMod);
453 clr = CAT02toHPE(clr);
454 clr = NonlinearCompression(clr, lpMod);
455 clr = ComputeCorrelates(clr, lpMod);
456
457 pOut ->J = clr.J;
458 pOut ->C = clr.C;
459 pOut ->h = clr.h;
460 }
461
cmsCIECAM02Reverse(cmsHANDLE hModel,const cmsJCh * pIn,cmsCIEXYZ * pOut)462 void CMSEXPORT cmsCIECAM02Reverse(cmsHANDLE hModel, const cmsJCh* pIn, cmsCIEXYZ* pOut)
463 {
464 CAM02COLOR clr;
465 cmsCIECAM02* lpMod = (cmsCIECAM02*) hModel;
466
467 _cmsAssert(lpMod != NULL);
468 _cmsAssert(pIn != NULL);
469 _cmsAssert(pOut != NULL);
470
471 memset(&clr, 0, sizeof(clr));
472
473 clr.J = pIn -> J;
474 clr.C = pIn -> C;
475 clr.h = pIn -> h;
476
477 clr = InverseCorrelates(clr, lpMod);
478 clr = InverseNonlinearity(clr, lpMod);
479 clr = HPEtoCAT02(clr);
480 clr = InverseChromaticAdaptation(clr, lpMod);
481 clr = CAT02toXYZ(clr);
482
483 pOut ->X = clr.XYZ[0];
484 pOut ->Y = clr.XYZ[1];
485 pOut ->Z = clr.XYZ[2];
486 }
487