1 //---------------------------------------------------------------------------------
2 //
3 // Little Color Management System
4 // Copyright (c) 1998-2010 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 // inter PCS conversions XYZ <-> CIE L* a* b*
30 /*
31
32
33 CIE 15:2004 CIELab is defined as:
34
35 L* = 116*f(Y/Yn) - 16 0 <= L* <= 100
36 a* = 500*[f(X/Xn) - f(Y/Yn)]
37 b* = 200*[f(Y/Yn) - f(Z/Zn)]
38
39 and
40
41 f(t) = t^(1/3) 1 >= t > (24/116)^3
42 (841/108)*t + (16/116) 0 <= t <= (24/116)^3
43
44
45 Reverse transform is:
46
47 X = Xn*[a* / 500 + (L* + 16) / 116] ^ 3 if (X/Xn) > (24/116)
48 = Xn*(a* / 500 + L* / 116) / 7.787 if (X/Xn) <= (24/116)
49
50
51
52 PCS in Lab2 is encoded as:
53
54 8 bit Lab PCS:
55
56 L* 0..100 into a 0..ff byte.
57 a* t + 128 range is -128.0 +127.0
58 b*
59
60 16 bit Lab PCS:
61
62 L* 0..100 into a 0..ff00 word.
63 a* t + 128 range is -128.0 +127.9961
64 b*
65
66
67
68 Interchange Space Component Actual Range Encoded Range
69 CIE XYZ X 0 -> 1.99997 0x0000 -> 0xffff
70 CIE XYZ Y 0 -> 1.99997 0x0000 -> 0xffff
71 CIE XYZ Z 0 -> 1.99997 0x0000 -> 0xffff
72
73 Version 2,3
74 -----------
75
76 CIELAB (16 bit) L* 0 -> 100.0 0x0000 -> 0xff00
77 CIELAB (16 bit) a* -128.0 -> +127.996 0x0000 -> 0x8000 -> 0xffff
78 CIELAB (16 bit) b* -128.0 -> +127.996 0x0000 -> 0x8000 -> 0xffff
79
80
81 Version 4
82 ---------
83
84 CIELAB (16 bit) L* 0 -> 100.0 0x0000 -> 0xffff
85 CIELAB (16 bit) a* -128.0 -> +127 0x0000 -> 0x8080 -> 0xffff
86 CIELAB (16 bit) b* -128.0 -> +127 0x0000 -> 0x8080 -> 0xffff
87
88 */
89
90 // Conversions
cmsXYZ2xyY(cmsCIExyY * Dest,const cmsCIEXYZ * Source)91 void CMSEXPORT cmsXYZ2xyY(cmsCIExyY* Dest, const cmsCIEXYZ* Source)
92 {
93 cmsFloat64Number ISum;
94
95 ISum = 1./(Source -> X + Source -> Y + Source -> Z);
96
97 Dest -> x = (Source -> X) * ISum;
98 Dest -> y = (Source -> Y) * ISum;
99 Dest -> Y = Source -> Y;
100 }
101
cmsxyY2XYZ(cmsCIEXYZ * Dest,const cmsCIExyY * Source)102 void CMSEXPORT cmsxyY2XYZ(cmsCIEXYZ* Dest, const cmsCIExyY* Source)
103 {
104 Dest -> X = (Source -> x / Source -> y) * Source -> Y;
105 Dest -> Y = Source -> Y;
106 Dest -> Z = ((1 - Source -> x - Source -> y) / Source -> y) * Source -> Y;
107 }
108
109 static
f(cmsFloat64Number t)110 cmsFloat64Number f(cmsFloat64Number t)
111 {
112 const cmsFloat64Number Limit = (24.0/116.0) * (24.0/116.0) * (24.0/116.0);
113
114 if (t <= Limit)
115 return (841.0/108.0) * t + (16.0/116.0);
116 else
117 return pow(t, 1.0/3.0);
118 }
119
120 static
f_1(cmsFloat64Number t)121 cmsFloat64Number f_1(cmsFloat64Number t)
122 {
123 const cmsFloat64Number Limit = (24.0/116.0);
124
125 if (t <= Limit) {
126 return (108.0/841.0) * (t - (16.0/116.0));
127 }
128
129 return t * t * t;
130 }
131
132
133 // Standard XYZ to Lab. it can handle negative XZY numbers in some cases
cmsXYZ2Lab(const cmsCIEXYZ * WhitePoint,cmsCIELab * Lab,const cmsCIEXYZ * xyz)134 void CMSEXPORT cmsXYZ2Lab(const cmsCIEXYZ* WhitePoint, cmsCIELab* Lab, const cmsCIEXYZ* xyz)
135 {
136 cmsFloat64Number fx, fy, fz;
137
138 if (WhitePoint == NULL)
139 WhitePoint = cmsD50_XYZ();
140
141 fx = f(xyz->X / WhitePoint->X);
142 fy = f(xyz->Y / WhitePoint->Y);
143 fz = f(xyz->Z / WhitePoint->Z);
144
145 Lab->L = 116.0*fy - 16.0;
146 Lab->a = 500.0*(fx - fy);
147 Lab->b = 200.0*(fy - fz);
148 }
149
150
151 // Standard XYZ to Lab. It can return negative XYZ in some cases
cmsLab2XYZ(const cmsCIEXYZ * WhitePoint,cmsCIEXYZ * xyz,const cmsCIELab * Lab)152 void CMSEXPORT cmsLab2XYZ(const cmsCIEXYZ* WhitePoint, cmsCIEXYZ* xyz, const cmsCIELab* Lab)
153 {
154 cmsFloat64Number x, y, z;
155
156 if (WhitePoint == NULL)
157 WhitePoint = cmsD50_XYZ();
158
159 y = (Lab-> L + 16.0) / 116.0;
160 x = y + 0.002 * Lab -> a;
161 z = y - 0.005 * Lab -> b;
162
163 xyz -> X = f_1(x) * WhitePoint -> X;
164 xyz -> Y = f_1(y) * WhitePoint -> Y;
165 xyz -> Z = f_1(z) * WhitePoint -> Z;
166
167 }
168
169 static
L2float2(cmsUInt16Number v)170 cmsFloat64Number L2float2(cmsUInt16Number v)
171 {
172 return (cmsFloat64Number) v / 652.800;
173 }
174
175 // the a/b part
176 static
ab2float2(cmsUInt16Number v)177 cmsFloat64Number ab2float2(cmsUInt16Number v)
178 {
179 return ((cmsFloat64Number) v / 256.0) - 128.0;
180 }
181
182 static
L2Fix2(cmsFloat64Number L)183 cmsUInt16Number L2Fix2(cmsFloat64Number L)
184 {
185 return _cmsQuickSaturateWord(L * 652.8);
186 }
187
188 static
ab2Fix2(cmsFloat64Number ab)189 cmsUInt16Number ab2Fix2(cmsFloat64Number ab)
190 {
191 return _cmsQuickSaturateWord((ab + 128.0) * 256.0);
192 }
193
194
195 static
L2float4(cmsUInt16Number v)196 cmsFloat64Number L2float4(cmsUInt16Number v)
197 {
198 return (cmsFloat64Number) v / 655.35;
199 }
200
201 // the a/b part
202 static
ab2float4(cmsUInt16Number v)203 cmsFloat64Number ab2float4(cmsUInt16Number v)
204 {
205 return ((cmsFloat64Number) v / 257.0) - 128.0;
206 }
207
208
cmsLabEncoded2FloatV2(cmsCIELab * Lab,const cmsUInt16Number wLab[3])209 void CMSEXPORT cmsLabEncoded2FloatV2(cmsCIELab* Lab, const cmsUInt16Number wLab[3])
210 {
211 Lab->L = L2float2(wLab[0]);
212 Lab->a = ab2float2(wLab[1]);
213 Lab->b = ab2float2(wLab[2]);
214 }
215
216
cmsLabEncoded2Float(cmsCIELab * Lab,const cmsUInt16Number wLab[3])217 void CMSEXPORT cmsLabEncoded2Float(cmsCIELab* Lab, const cmsUInt16Number wLab[3])
218 {
219 Lab->L = L2float4(wLab[0]);
220 Lab->a = ab2float4(wLab[1]);
221 Lab->b = ab2float4(wLab[2]);
222 }
223
224 static
Clamp_L_doubleV2(cmsFloat64Number L)225 cmsFloat64Number Clamp_L_doubleV2(cmsFloat64Number L)
226 {
227 const cmsFloat64Number L_max = (cmsFloat64Number) (0xFFFF * 100.0) / 0xFF00;
228
229 if (L < 0) L = 0;
230 if (L > L_max) L = L_max;
231
232 return L;
233 }
234
235
236 static
Clamp_ab_doubleV2(cmsFloat64Number ab)237 cmsFloat64Number Clamp_ab_doubleV2(cmsFloat64Number ab)
238 {
239 if (ab < MIN_ENCODEABLE_ab2) ab = MIN_ENCODEABLE_ab2;
240 if (ab > MAX_ENCODEABLE_ab2) ab = MAX_ENCODEABLE_ab2;
241
242 return ab;
243 }
244
cmsFloat2LabEncodedV2(cmsUInt16Number wLab[3],const cmsCIELab * fLab)245 void CMSEXPORT cmsFloat2LabEncodedV2(cmsUInt16Number wLab[3], const cmsCIELab* fLab)
246 {
247 cmsCIELab Lab;
248
249 Lab.L = Clamp_L_doubleV2(fLab ->L);
250 Lab.a = Clamp_ab_doubleV2(fLab ->a);
251 Lab.b = Clamp_ab_doubleV2(fLab ->b);
252
253 wLab[0] = L2Fix2(Lab.L);
254 wLab[1] = ab2Fix2(Lab.a);
255 wLab[2] = ab2Fix2(Lab.b);
256 }
257
258
259 static
Clamp_L_doubleV4(cmsFloat64Number L)260 cmsFloat64Number Clamp_L_doubleV4(cmsFloat64Number L)
261 {
262 if (L < 0) L = 0;
263 if (L > 100.0) L = 100.0;
264
265 return L;
266 }
267
268 static
Clamp_ab_doubleV4(cmsFloat64Number ab)269 cmsFloat64Number Clamp_ab_doubleV4(cmsFloat64Number ab)
270 {
271 if (ab < MIN_ENCODEABLE_ab4) ab = MIN_ENCODEABLE_ab4;
272 if (ab > MAX_ENCODEABLE_ab4) ab = MAX_ENCODEABLE_ab4;
273
274 return ab;
275 }
276
277 static
L2Fix4(cmsFloat64Number L)278 cmsUInt16Number L2Fix4(cmsFloat64Number L)
279 {
280 return _cmsQuickSaturateWord(L * 655.35);
281 }
282
283 static
ab2Fix4(cmsFloat64Number ab)284 cmsUInt16Number ab2Fix4(cmsFloat64Number ab)
285 {
286 return _cmsQuickSaturateWord((ab + 128.0) * 257.0);
287 }
288
cmsFloat2LabEncoded(cmsUInt16Number wLab[3],const cmsCIELab * fLab)289 void CMSEXPORT cmsFloat2LabEncoded(cmsUInt16Number wLab[3], const cmsCIELab* fLab)
290 {
291 cmsCIELab Lab;
292
293 Lab.L = Clamp_L_doubleV4(fLab ->L);
294 Lab.a = Clamp_ab_doubleV4(fLab ->a);
295 Lab.b = Clamp_ab_doubleV4(fLab ->b);
296
297 wLab[0] = L2Fix4(Lab.L);
298 wLab[1] = ab2Fix4(Lab.a);
299 wLab[2] = ab2Fix4(Lab.b);
300 }
301
302 // Auxiliar: convert to Radians
303 static
RADIANS(cmsFloat64Number deg)304 cmsFloat64Number RADIANS(cmsFloat64Number deg)
305 {
306 return (deg * M_PI) / 180.;
307 }
308
309
310 // Auxiliar: atan2 but operating in degrees and returning 0 if a==b==0
311 static
atan2deg(cmsFloat64Number a,cmsFloat64Number b)312 cmsFloat64Number atan2deg(cmsFloat64Number a, cmsFloat64Number b)
313 {
314 cmsFloat64Number h;
315
316 if (a == 0 && b == 0)
317 h = 0;
318 else
319 h = atan2(a, b);
320
321 h *= (180. / M_PI);
322
323 while (h > 360.)
324 h -= 360.;
325
326 while ( h < 0)
327 h += 360.;
328
329 return h;
330 }
331
332
333 // Auxiliar: Square
334 static
Sqr(cmsFloat64Number v)335 cmsFloat64Number Sqr(cmsFloat64Number v)
336 {
337 return v * v;
338 }
339 // From cylindrical coordinates. No check is performed, then negative values are allowed
cmsLab2LCh(cmsCIELCh * LCh,const cmsCIELab * Lab)340 void CMSEXPORT cmsLab2LCh(cmsCIELCh* LCh, const cmsCIELab* Lab)
341 {
342 LCh -> L = Lab -> L;
343 LCh -> C = pow(Sqr(Lab ->a) + Sqr(Lab ->b), 0.5);
344 LCh -> h = atan2deg(Lab ->b, Lab ->a);
345 }
346
347
348 // To cylindrical coordinates. No check is performed, then negative values are allowed
cmsLCh2Lab(cmsCIELab * Lab,const cmsCIELCh * LCh)349 void CMSEXPORT cmsLCh2Lab(cmsCIELab* Lab, const cmsCIELCh* LCh)
350 {
351 cmsFloat64Number h = (LCh -> h * M_PI) / 180.0;
352
353 Lab -> L = LCh -> L;
354 Lab -> a = LCh -> C * cos(h);
355 Lab -> b = LCh -> C * sin(h);
356 }
357
358 // In XYZ All 3 components are encoded using 1.15 fixed point
359 static
XYZ2Fix(cmsFloat64Number d)360 cmsUInt16Number XYZ2Fix(cmsFloat64Number d)
361 {
362 return _cmsQuickSaturateWord(d * 32768.0);
363 }
364
cmsFloat2XYZEncoded(cmsUInt16Number XYZ[3],const cmsCIEXYZ * fXYZ)365 void CMSEXPORT cmsFloat2XYZEncoded(cmsUInt16Number XYZ[3], const cmsCIEXYZ* fXYZ)
366 {
367 cmsCIEXYZ xyz;
368
369 xyz.X = fXYZ -> X;
370 xyz.Y = fXYZ -> Y;
371 xyz.Z = fXYZ -> Z;
372
373 // Clamp to encodeable values.
374 if (xyz.Y <= 0) {
375
376 xyz.X = 0;
377 xyz.Y = 0;
378 xyz.Z = 0;
379 }
380
381 if (xyz.X > MAX_ENCODEABLE_XYZ)
382 xyz.X = MAX_ENCODEABLE_XYZ;
383
384 if (xyz.X < 0)
385 xyz.X = 0;
386
387 if (xyz.Y > MAX_ENCODEABLE_XYZ)
388 xyz.Y = MAX_ENCODEABLE_XYZ;
389
390 if (xyz.Y < 0)
391 xyz.Y = 0;
392
393 if (xyz.Z > MAX_ENCODEABLE_XYZ)
394 xyz.Z = MAX_ENCODEABLE_XYZ;
395
396 if (xyz.Z < 0)
397 xyz.Z = 0;
398
399
400 XYZ[0] = XYZ2Fix(xyz.X);
401 XYZ[1] = XYZ2Fix(xyz.Y);
402 XYZ[2] = XYZ2Fix(xyz.Z);
403 }
404
405
406 // To convert from Fixed 1.15 point to cmsFloat64Number
407 static
XYZ2float(cmsUInt16Number v)408 cmsFloat64Number XYZ2float(cmsUInt16Number v)
409 {
410 cmsS15Fixed16Number fix32;
411
412 // From 1.15 to 15.16
413 fix32 = v << 1;
414
415 // From fixed 15.16 to cmsFloat64Number
416 return _cms15Fixed16toDouble(fix32);
417 }
418
419
cmsXYZEncoded2Float(cmsCIEXYZ * fXYZ,const cmsUInt16Number XYZ[3])420 void CMSEXPORT cmsXYZEncoded2Float(cmsCIEXYZ* fXYZ, const cmsUInt16Number XYZ[3])
421 {
422 fXYZ -> X = XYZ2float(XYZ[0]);
423 fXYZ -> Y = XYZ2float(XYZ[1]);
424 fXYZ -> Z = XYZ2float(XYZ[2]);
425 }
426
427
428 // Returns dE on two Lab values
cmsDeltaE(const cmsCIELab * Lab1,const cmsCIELab * Lab2)429 cmsFloat64Number CMSEXPORT cmsDeltaE(const cmsCIELab* Lab1, const cmsCIELab* Lab2)
430 {
431 cmsFloat64Number dL, da, db;
432
433 dL = fabs(Lab1 -> L - Lab2 -> L);
434 da = fabs(Lab1 -> a - Lab2 -> a);
435 db = fabs(Lab1 -> b - Lab2 -> b);
436
437 return pow(Sqr(dL) + Sqr(da) + Sqr(db), 0.5);
438 }
439
440
441 // Return the CIE94 Delta E
cmsCIE94DeltaE(const cmsCIELab * Lab1,const cmsCIELab * Lab2)442 cmsFloat64Number CMSEXPORT cmsCIE94DeltaE(const cmsCIELab* Lab1, const cmsCIELab* Lab2)
443 {
444 cmsCIELCh LCh1, LCh2;
445 cmsFloat64Number dE, dL, dC, dh, dhsq;
446 cmsFloat64Number c12, sc, sh;
447
448 dL = fabs(Lab1 ->L - Lab2 ->L);
449
450 cmsLab2LCh(&LCh1, Lab1);
451 cmsLab2LCh(&LCh2, Lab2);
452
453 dC = fabs(LCh1.C - LCh2.C);
454 dE = cmsDeltaE(Lab1, Lab2);
455
456 dhsq = Sqr(dE) - Sqr(dL) - Sqr(dC);
457 if (dhsq < 0)
458 dh = 0;
459 else
460 dh = pow(dhsq, 0.5);
461
462 c12 = sqrt(LCh1.C * LCh2.C);
463
464 sc = 1.0 + (0.048 * c12);
465 sh = 1.0 + (0.014 * c12);
466
467 return sqrt(Sqr(dL) + Sqr(dC) / Sqr(sc) + Sqr(dh) / Sqr(sh));
468 }
469
470
471 // Auxiliary
472 static
ComputeLBFD(const cmsCIELab * Lab)473 cmsFloat64Number ComputeLBFD(const cmsCIELab* Lab)
474 {
475 cmsFloat64Number yt;
476
477 if (Lab->L > 7.996969)
478 yt = (Sqr((Lab->L+16)/116)*((Lab->L+16)/116))*100;
479 else
480 yt = 100 * (Lab->L / 903.3);
481
482 return (54.6 * (M_LOG10E * (log(yt + 1.5))) - 9.6);
483 }
484
485
486
487 // bfd - gets BFD(1:1) difference between Lab1, Lab2
cmsBFDdeltaE(const cmsCIELab * Lab1,const cmsCIELab * Lab2)488 cmsFloat64Number CMSEXPORT cmsBFDdeltaE(const cmsCIELab* Lab1, const cmsCIELab* Lab2)
489 {
490 cmsFloat64Number lbfd1,lbfd2,AveC,Aveh,dE,deltaL,
491 deltaC,deltah,dc,t,g,dh,rh,rc,rt,bfd;
492 cmsCIELCh LCh1, LCh2;
493
494
495 lbfd1 = ComputeLBFD(Lab1);
496 lbfd2 = ComputeLBFD(Lab2);
497 deltaL = lbfd2 - lbfd1;
498
499 cmsLab2LCh(&LCh1, Lab1);
500 cmsLab2LCh(&LCh2, Lab2);
501
502 deltaC = LCh2.C - LCh1.C;
503 AveC = (LCh1.C+LCh2.C)/2;
504 Aveh = (LCh1.h+LCh2.h)/2;
505
506 dE = cmsDeltaE(Lab1, Lab2);
507
508 if (Sqr(dE)>(Sqr(Lab2->L-Lab1->L)+Sqr(deltaC)))
509 deltah = sqrt(Sqr(dE)-Sqr(Lab2->L-Lab1->L)-Sqr(deltaC));
510 else
511 deltah =0;
512
513
514 dc = 0.035 * AveC / (1 + 0.00365 * AveC)+0.521;
515 g = sqrt(Sqr(Sqr(AveC))/(Sqr(Sqr(AveC))+14000));
516 t = 0.627+(0.055*cos((Aveh-254)/(180/M_PI))-
517 0.040*cos((2*Aveh-136)/(180/M_PI))+
518 0.070*cos((3*Aveh-31)/(180/M_PI))+
519 0.049*cos((4*Aveh+114)/(180/M_PI))-
520 0.015*cos((5*Aveh-103)/(180/M_PI)));
521
522 dh = dc*(g*t+1-g);
523 rh = -0.260*cos((Aveh-308)/(180/M_PI))-
524 0.379*cos((2*Aveh-160)/(180/M_PI))-
525 0.636*cos((3*Aveh+254)/(180/M_PI))+
526 0.226*cos((4*Aveh+140)/(180/M_PI))-
527 0.194*cos((5*Aveh+280)/(180/M_PI));
528
529 rc = sqrt((AveC*AveC*AveC*AveC*AveC*AveC)/((AveC*AveC*AveC*AveC*AveC*AveC)+70000000));
530 rt = rh*rc;
531
532 bfd = sqrt(Sqr(deltaL)+Sqr(deltaC/dc)+Sqr(deltah/dh)+(rt*(deltaC/dc)*(deltah/dh)));
533
534 return bfd;
535 }
536
537
538 // cmc - CMC(l:c) difference between Lab1, Lab2
cmsCMCdeltaE(const cmsCIELab * Lab1,const cmsCIELab * Lab2,cmsFloat64Number l,cmsFloat64Number c)539 cmsFloat64Number CMSEXPORT cmsCMCdeltaE(const cmsCIELab* Lab1, const cmsCIELab* Lab2, cmsFloat64Number l, cmsFloat64Number c)
540 {
541 cmsFloat64Number dE,dL,dC,dh,sl,sc,sh,t,f,cmc;
542 cmsCIELCh LCh1, LCh2;
543
544 if (Lab1 ->L == 0 && Lab2 ->L == 0) return 0;
545
546 cmsLab2LCh(&LCh1, Lab1);
547 cmsLab2LCh(&LCh2, Lab2);
548
549
550 dL = Lab2->L-Lab1->L;
551 dC = LCh2.C-LCh1.C;
552
553 dE = cmsDeltaE(Lab1, Lab2);
554
555 if (Sqr(dE)>(Sqr(dL)+Sqr(dC)))
556 dh = sqrt(Sqr(dE)-Sqr(dL)-Sqr(dC));
557 else
558 dh =0;
559
560 if ((LCh1.h > 164) && (LCh1.h < 345))
561 t = 0.56 + fabs(0.2 * cos(((LCh1.h + 168)/(180/M_PI))));
562 else
563 t = 0.36 + fabs(0.4 * cos(((LCh1.h + 35 )/(180/M_PI))));
564
565 sc = 0.0638 * LCh1.C / (1 + 0.0131 * LCh1.C) + 0.638;
566 sl = 0.040975 * Lab1->L /(1 + 0.01765 * Lab1->L);
567
568 if (Lab1->L<16)
569 sl = 0.511;
570
571 f = sqrt((LCh1.C * LCh1.C * LCh1.C * LCh1.C)/((LCh1.C * LCh1.C * LCh1.C * LCh1.C)+1900));
572 sh = sc*(t*f+1-f);
573 cmc = sqrt(Sqr(dL/(l*sl))+Sqr(dC/(c*sc))+Sqr(dh/sh));
574
575 return cmc;
576 }
577
578 // dE2000 The weightings KL, KC and KH can be modified to reflect the relative
579 // importance of lightness, chroma and hue in different industrial applications
cmsCIE2000DeltaE(const cmsCIELab * Lab1,const cmsCIELab * Lab2,cmsFloat64Number Kl,cmsFloat64Number Kc,cmsFloat64Number Kh)580 cmsFloat64Number CMSEXPORT cmsCIE2000DeltaE(const cmsCIELab* Lab1, const cmsCIELab* Lab2,
581 cmsFloat64Number Kl, cmsFloat64Number Kc, cmsFloat64Number Kh)
582 {
583 cmsFloat64Number L1 = Lab1->L;
584 cmsFloat64Number a1 = Lab1->a;
585 cmsFloat64Number b1 = Lab1->b;
586 cmsFloat64Number C = sqrt( Sqr(a1) + Sqr(b1) );
587
588 cmsFloat64Number Ls = Lab2 ->L;
589 cmsFloat64Number as = Lab2 ->a;
590 cmsFloat64Number bs = Lab2 ->b;
591 cmsFloat64Number Cs = sqrt( Sqr(as) + Sqr(bs) );
592
593 cmsFloat64Number G = 0.5 * ( 1 - sqrt(pow((C + Cs) / 2 , 7.0) / (pow((C + Cs) / 2, 7.0) + pow(25.0, 7.0) ) ));
594
595 cmsFloat64Number a_p = (1 + G ) * a1;
596 cmsFloat64Number b_p = b1;
597 cmsFloat64Number C_p = sqrt( Sqr(a_p) + Sqr(b_p));
598 cmsFloat64Number h_p = atan2deg(b_p, a_p);
599
600
601 cmsFloat64Number a_ps = (1 + G) * as;
602 cmsFloat64Number b_ps = bs;
603 cmsFloat64Number C_ps = sqrt(Sqr(a_ps) + Sqr(b_ps));
604 cmsFloat64Number h_ps = atan2deg(b_ps, a_ps);
605
606 cmsFloat64Number meanC_p =(C_p + C_ps) / 2;
607
608 cmsFloat64Number hps_plus_hp = h_ps + h_p;
609 cmsFloat64Number hps_minus_hp = h_ps - h_p;
610
611 cmsFloat64Number meanh_p = fabs(hps_minus_hp) <= 180.000001 ? (hps_plus_hp)/2 :
612 (hps_plus_hp) < 360 ? (hps_plus_hp + 360)/2 :
613 (hps_plus_hp - 360)/2;
614
615 cmsFloat64Number delta_h = (hps_minus_hp) <= -180.000001 ? (hps_minus_hp + 360) :
616 (hps_minus_hp) > 180 ? (hps_minus_hp - 360) :
617 (hps_minus_hp);
618 cmsFloat64Number delta_L = (Ls - L1);
619 cmsFloat64Number delta_C = (C_ps - C_p );
620
621
622 cmsFloat64Number delta_H =2 * sqrt(C_ps*C_p) * sin(RADIANS(delta_h) / 2);
623
624 cmsFloat64Number T = 1 - 0.17 * cos(RADIANS(meanh_p-30))
625 + 0.24 * cos(RADIANS(2*meanh_p))
626 + 0.32 * cos(RADIANS(3*meanh_p + 6))
627 - 0.2 * cos(RADIANS(4*meanh_p - 63));
628
629 cmsFloat64Number Sl = 1 + (0.015 * Sqr((Ls + L1) /2- 50) )/ sqrt(20 + Sqr( (Ls+L1)/2 - 50) );
630
631 cmsFloat64Number Sc = 1 + 0.045 * (C_p + C_ps)/2;
632 cmsFloat64Number Sh = 1 + 0.015 * ((C_ps + C_p)/2) * T;
633
634 cmsFloat64Number delta_ro = 30 * exp( -Sqr(((meanh_p - 275 ) / 25)));
635
636 cmsFloat64Number Rc = 2 * sqrt(( pow(meanC_p, 7.0) )/( pow(meanC_p, 7.0) + pow(25.0, 7.0)));
637
638 cmsFloat64Number Rt = -sin(2 * RADIANS(delta_ro)) * Rc;
639
640 cmsFloat64Number deltaE00 = sqrt( Sqr(delta_L /(Sl * Kl)) +
641 Sqr(delta_C/(Sc * Kc)) +
642 Sqr(delta_H/(Sh * Kh)) +
643 Rt*(delta_C/(Sc * Kc)) * (delta_H / (Sh * Kh)));
644
645 return deltaE00;
646 }
647
648 // This function returns a number of gridpoints to be used as LUT table. It assumes same number
649 // of gripdpoints in all dimensions. Flags may override the choice.
_cmsReasonableGridpointsByColorspace(cmsColorSpaceSignature Colorspace,cmsUInt32Number dwFlags)650 int _cmsReasonableGridpointsByColorspace(cmsColorSpaceSignature Colorspace, cmsUInt32Number dwFlags)
651 {
652 int nChannels;
653
654 // Already specified?
655 if (dwFlags & 0x00FF0000) {
656 // Yes, grab'em
657 return (dwFlags >> 16) & 0xFF;
658 }
659
660 nChannels = cmsChannelsOf(Colorspace);
661
662 // HighResPrecalc is maximum resolution
663 if (dwFlags & cmsFLAGS_HIGHRESPRECALC) {
664
665 if (nChannels > 4)
666 return 7; // 7 for Hifi
667
668 if (nChannels == 4) // 23 for CMYK
669 return 23;
670
671 return 49; // 49 for RGB and others
672 }
673
674
675 // LowResPrecal is lower resolution
676 if (dwFlags & cmsFLAGS_LOWRESPRECALC) {
677
678 if (nChannels > 4)
679 return 6; // 6 for more than 4 channels
680
681 if (nChannels == 1)
682 return 33; // For monochrome
683
684 return 17; // 17 for remaining
685 }
686
687 // Default values
688 if (nChannels > 4)
689 return 7; // 7 for Hifi
690
691 if (nChannels == 4)
692 return 17; // 17 for CMYK
693
694 return 33; // 33 for RGB
695 }
696
697
_cmsEndPointsBySpace(cmsColorSpaceSignature Space,cmsUInt16Number ** White,cmsUInt16Number ** Black,cmsUInt32Number * nOutputs)698 cmsBool _cmsEndPointsBySpace(cmsColorSpaceSignature Space,
699 cmsUInt16Number **White,
700 cmsUInt16Number **Black,
701 cmsUInt32Number *nOutputs)
702 {
703 // Only most common spaces
704
705 static cmsUInt16Number RGBblack[4] = { 0, 0, 0 };
706 static cmsUInt16Number RGBwhite[4] = { 0xffff, 0xffff, 0xffff };
707 static cmsUInt16Number CMYKblack[4] = { 0xffff, 0xffff, 0xffff, 0xffff }; // 400% of ink
708 static cmsUInt16Number CMYKwhite[4] = { 0, 0, 0, 0 };
709 static cmsUInt16Number LABblack[4] = { 0, 0x8080, 0x8080 }; // V4 Lab encoding
710 static cmsUInt16Number LABwhite[4] = { 0xFFFF, 0x8080, 0x8080 };
711 static cmsUInt16Number CMYblack[4] = { 0xffff, 0xffff, 0xffff };
712 static cmsUInt16Number CMYwhite[4] = { 0, 0, 0 };
713 static cmsUInt16Number Grayblack[4] = { 0 };
714 static cmsUInt16Number GrayWhite[4] = { 0xffff };
715
716 switch (Space) {
717
718 case cmsSigGrayData: if (White) *White = GrayWhite;
719 if (Black) *Black = Grayblack;
720 if (nOutputs) *nOutputs = 1;
721 return TRUE;
722
723 case cmsSigRgbData: if (White) *White = RGBwhite;
724 if (Black) *Black = RGBblack;
725 if (nOutputs) *nOutputs = 3;
726 return TRUE;
727
728 case cmsSigLabData: if (White) *White = LABwhite;
729 if (Black) *Black = LABblack;
730 if (nOutputs) *nOutputs = 3;
731 return TRUE;
732
733 case cmsSigCmykData: if (White) *White = CMYKwhite;
734 if (Black) *Black = CMYKblack;
735 if (nOutputs) *nOutputs = 4;
736 return TRUE;
737
738 case cmsSigCmyData: if (White) *White = CMYwhite;
739 if (Black) *Black = CMYblack;
740 if (nOutputs) *nOutputs = 3;
741 return TRUE;
742
743 default:;
744 }
745
746 return FALSE;
747 }
748
749
750
751 // Several utilities -------------------------------------------------------
752
753 // Translate from our colorspace to ICC representation
754
_cmsICCcolorSpace(int OurNotation)755 cmsColorSpaceSignature CMSEXPORT _cmsICCcolorSpace(int OurNotation)
756 {
757 switch (OurNotation) {
758
759 case 1:
760 case PT_GRAY: return cmsSigGrayData;
761
762 case 2:
763 case PT_RGB: return cmsSigRgbData;
764
765 case PT_CMY: return cmsSigCmyData;
766 case PT_CMYK: return cmsSigCmykData;
767 case PT_YCbCr:return cmsSigYCbCrData;
768 case PT_YUV: return cmsSigLuvData;
769 case PT_XYZ: return cmsSigXYZData;
770
771 case PT_LabV2:
772 case PT_Lab: return cmsSigLabData;
773
774 case PT_YUVK: return cmsSigLuvKData;
775 case PT_HSV: return cmsSigHsvData;
776 case PT_HLS: return cmsSigHlsData;
777 case PT_Yxy: return cmsSigYxyData;
778
779 case PT_MCH1: return cmsSigMCH1Data;
780 case PT_MCH2: return cmsSigMCH2Data;
781 case PT_MCH3: return cmsSigMCH3Data;
782 case PT_MCH4: return cmsSigMCH4Data;
783 case PT_MCH5: return cmsSigMCH5Data;
784 case PT_MCH6: return cmsSigMCH6Data;
785 case PT_MCH7: return cmsSigMCH7Data;
786 case PT_MCH8: return cmsSigMCH8Data;
787
788 case PT_MCH9: return cmsSigMCH9Data;
789 case PT_MCH10: return cmsSigMCHAData;
790 case PT_MCH11: return cmsSigMCHBData;
791 case PT_MCH12: return cmsSigMCHCData;
792 case PT_MCH13: return cmsSigMCHDData;
793 case PT_MCH14: return cmsSigMCHEData;
794 case PT_MCH15: return cmsSigMCHFData;
795
796 default: return (cmsColorSpaceSignature) (-1);
797 }
798 }
799
800
_cmsLCMScolorSpace(cmsColorSpaceSignature ProfileSpace)801 int CMSEXPORT _cmsLCMScolorSpace(cmsColorSpaceSignature ProfileSpace)
802 {
803 switch (ProfileSpace) {
804
805 case cmsSigGrayData: return PT_GRAY;
806 case cmsSigRgbData: return PT_RGB;
807 case cmsSigCmyData: return PT_CMY;
808 case cmsSigCmykData: return PT_CMYK;
809 case cmsSigYCbCrData:return PT_YCbCr;
810 case cmsSigLuvData: return PT_YUV;
811 case cmsSigXYZData: return PT_XYZ;
812 case cmsSigLabData: return PT_Lab;
813 case cmsSigLuvKData: return PT_YUVK;
814 case cmsSigHsvData: return PT_HSV;
815 case cmsSigHlsData: return PT_HLS;
816 case cmsSigYxyData: return PT_Yxy;
817
818 case cmsSig1colorData:
819 case cmsSigMCH1Data: return PT_MCH1;
820
821 case cmsSig2colorData:
822 case cmsSigMCH2Data: return PT_MCH2;
823
824 case cmsSig3colorData:
825 case cmsSigMCH3Data: return PT_MCH3;
826
827 case cmsSig4colorData:
828 case cmsSigMCH4Data: return PT_MCH4;
829
830 case cmsSig5colorData:
831 case cmsSigMCH5Data: return PT_MCH5;
832
833 case cmsSig6colorData:
834 case cmsSigMCH6Data: return PT_MCH6;
835
836 case cmsSigMCH7Data:
837 case cmsSig7colorData:return PT_MCH7;
838
839 case cmsSigMCH8Data:
840 case cmsSig8colorData:return PT_MCH8;
841
842 case cmsSigMCH9Data:
843 case cmsSig9colorData:return PT_MCH9;
844
845 case cmsSigMCHAData:
846 case cmsSig10colorData:return PT_MCH10;
847
848 case cmsSigMCHBData:
849 case cmsSig11colorData:return PT_MCH11;
850
851 case cmsSigMCHCData:
852 case cmsSig12colorData:return PT_MCH12;
853
854 case cmsSigMCHDData:
855 case cmsSig13colorData:return PT_MCH13;
856
857 case cmsSigMCHEData:
858 case cmsSig14colorData:return PT_MCH14;
859
860 case cmsSigMCHFData:
861 case cmsSig15colorData:return PT_MCH15;
862
863 default: return (cmsColorSpaceSignature) (-1);
864 }
865 }
866
867
cmsChannelsOf(cmsColorSpaceSignature ColorSpace)868 cmsUInt32Number CMSEXPORT cmsChannelsOf(cmsColorSpaceSignature ColorSpace)
869 {
870 switch (ColorSpace) {
871
872 case cmsSigMCH1Data:
873 case cmsSig1colorData:
874 case cmsSigGrayData: return 1;
875
876 case cmsSigMCH2Data:
877 case cmsSig2colorData: return 2;
878
879 case cmsSigXYZData:
880 case cmsSigLabData:
881 case cmsSigLuvData:
882 case cmsSigYCbCrData:
883 case cmsSigYxyData:
884 case cmsSigRgbData:
885 case cmsSigHsvData:
886 case cmsSigHlsData:
887 case cmsSigCmyData:
888 case cmsSigMCH3Data:
889 case cmsSig3colorData: return 3;
890
891 case cmsSigLuvKData:
892 case cmsSigCmykData:
893 case cmsSigMCH4Data:
894 case cmsSig4colorData: return 4;
895
896 case cmsSigMCH5Data:
897 case cmsSig5colorData: return 5;
898
899 case cmsSigMCH6Data:
900 case cmsSig6colorData: return 6;
901
902 case cmsSigMCH7Data:
903 case cmsSig7colorData: return 7;
904
905 case cmsSigMCH8Data:
906 case cmsSig8colorData: return 8;
907
908 case cmsSigMCH9Data:
909 case cmsSig9colorData: return 9;
910
911 case cmsSigMCHAData:
912 case cmsSig10colorData: return 10;
913
914 case cmsSigMCHBData:
915 case cmsSig11colorData: return 11;
916
917 case cmsSigMCHCData:
918 case cmsSig12colorData: return 12;
919
920 case cmsSigMCHDData:
921 case cmsSig13colorData: return 13;
922
923 case cmsSigMCHEData:
924 case cmsSig14colorData: return 14;
925
926 case cmsSigMCHFData:
927 case cmsSig15colorData: return 15;
928
929 default: return 3;
930 }
931 }
932