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