1 /*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
3 *
4 * This code is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 only, as
6 * published by the Free Software Foundation. Oracle designates this
7 * particular file as subject to the "Classpath" exception as provided
8 * by Oracle in the LICENSE file that accompanied this code.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 */
24
25 // This file is available under and governed by the GNU General Public
26 // License version 2 only, as published by the Free Software Foundation.
27 // However, the following notice accompanied the original version of this
28 // file:
29 //
30 //---------------------------------------------------------------------------------
31 //
32 // Little Color Management System
33 // Copyright (c) 1998-2010 Marti Maria Saguer
34 //
35 // Permission is hereby granted, free of charge, to any person obtaining
36 // a copy of this software and associated documentation files (the "Software"),
37 // to deal in the Software without restriction, including without limitation
38 // the rights to use, copy, modify, merge, publish, distribute, sublicense,
39 // and/or sell copies of the Software, and to permit persons to whom the Software
40 // is furnished to do so, subject to the following conditions:
41 //
42 // The above copyright notice and this permission notice shall be included in
43 // all copies or substantial portions of the Software.
44 //
45 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
46 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO
47 // THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
48 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
49 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
50 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
51 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
52 //
53 //---------------------------------------------------------------------------------
54 //
55
56 #include "lcms2_internal.h"
57
58 // inter PCS conversions XYZ <-> CIE L* a* b*
59 /*
60
61
62 CIE 15:2004 CIELab is defined as:
63
64 L* = 116*f(Y/Yn) - 16 0 <= L* <= 100
65 a* = 500*[f(X/Xn) - f(Y/Yn)]
66 b* = 200*[f(Y/Yn) - f(Z/Zn)]
67
68 and
69
70 f(t) = t^(1/3) 1 >= t > (24/116)^3
71 (841/108)*t + (16/116) 0 <= t <= (24/116)^3
72
73
74 Reverse transform is:
75
76 X = Xn*[a* / 500 + (L* + 16) / 116] ^ 3 if (X/Xn) > (24/116)
77 = Xn*(a* / 500 + L* / 116) / 7.787 if (X/Xn) <= (24/116)
78
79
80
81 PCS in Lab2 is encoded as:
82
83 8 bit Lab PCS:
84
85 L* 0..100 into a 0..ff byte.
86 a* t + 128 range is -128.0 +127.0
87 b*
88
89 16 bit Lab PCS:
90
91 L* 0..100 into a 0..ff00 word.
92 a* t + 128 range is -128.0 +127.9961
93 b*
94
95
96
97 Interchange Space Component Actual Range Encoded Range
98 CIE XYZ X 0 -> 1.99997 0x0000 -> 0xffff
99 CIE XYZ Y 0 -> 1.99997 0x0000 -> 0xffff
100 CIE XYZ Z 0 -> 1.99997 0x0000 -> 0xffff
101
102 Version 2,3
103 -----------
104
105 CIELAB (16 bit) L* 0 -> 100.0 0x0000 -> 0xff00
106 CIELAB (16 bit) a* -128.0 -> +127.996 0x0000 -> 0x8000 -> 0xffff
107 CIELAB (16 bit) b* -128.0 -> +127.996 0x0000 -> 0x8000 -> 0xffff
108
109
110 Version 4
111 ---------
112
113 CIELAB (16 bit) L* 0 -> 100.0 0x0000 -> 0xffff
114 CIELAB (16 bit) a* -128.0 -> +127 0x0000 -> 0x8080 -> 0xffff
115 CIELAB (16 bit) b* -128.0 -> +127 0x0000 -> 0x8080 -> 0xffff
116
117 */
118
119 // Conversions
120 void CMSEXPORT cmsXYZ2xyY(cmsCIExyY* Dest, const cmsCIEXYZ* Source)
121 {
122 cmsFloat64Number ISum;
123
124 ISum = 1./(Source -> X + Source -> Y + Source -> Z);
125
126 Dest -> x = (Source -> X) * ISum;
127 Dest -> y = (Source -> Y) * ISum;
128 Dest -> Y = Source -> Y;
129 }
130
131 void CMSEXPORT cmsxyY2XYZ(cmsCIEXYZ* Dest, const cmsCIExyY* Source)
132 {
133 Dest -> X = (Source -> x / Source -> y) * Source -> Y;
134 Dest -> Y = Source -> Y;
135 Dest -> Z = ((1 - Source -> x - Source -> y) / Source -> y) * Source -> Y;
136 }
137
138 static
139 cmsFloat64Number f(cmsFloat64Number t)
140 {
141 const cmsFloat64Number Limit = (24.0/116.0) * (24.0/116.0) * (24.0/116.0);
142
143 if (t <= Limit)
144 return (841.0/108.0) * t + (16.0/116.0);
145 else
146 return pow(t, 1.0/3.0);
147 }
148
149 static
150 cmsFloat64Number f_1(cmsFloat64Number t)
151 {
152 const cmsFloat64Number Limit = (24.0/116.0);
153
154 if (t <= Limit) {
155 return (108.0/841.0) * (t - (16.0/116.0));
156 }
157
158 return t * t * t;
159 }
160
161
162 // Standard XYZ to Lab. it can handle negative XZY numbers in some cases
163 void CMSEXPORT cmsXYZ2Lab(const cmsCIEXYZ* WhitePoint, cmsCIELab* Lab, const cmsCIEXYZ* xyz)
164 {
165 cmsFloat64Number fx, fy, fz;
166
167 if (WhitePoint == NULL)
168 WhitePoint = cmsD50_XYZ();
169
170 fx = f(xyz->X / WhitePoint->X);
171 fy = f(xyz->Y / WhitePoint->Y);
172 fz = f(xyz->Z / WhitePoint->Z);
173
174 Lab->L = 116.0*fy - 16.0;
175 Lab->a = 500.0*(fx - fy);
176 Lab->b = 200.0*(fy - fz);
177 }
178
179
180 // Standard XYZ to Lab. It can return negative XYZ in some cases
181 void CMSEXPORT cmsLab2XYZ(const cmsCIEXYZ* WhitePoint, cmsCIEXYZ* xyz, const cmsCIELab* Lab)
182 {
183 cmsFloat64Number x, y, z;
184
185 if (WhitePoint == NULL)
186 WhitePoint = cmsD50_XYZ();
187
188 y = (Lab-> L + 16.0) / 116.0;
189 x = y + 0.002 * Lab -> a;
190 z = y - 0.005 * Lab -> b;
191
192 xyz -> X = f_1(x) * WhitePoint -> X;
193 xyz -> Y = f_1(y) * WhitePoint -> Y;
194 xyz -> Z = f_1(z) * WhitePoint -> Z;
195
196 }
197
198 static
199 cmsFloat64Number L2float2(cmsUInt16Number v)
200 {
201 return (cmsFloat64Number) v / 652.800;
202 }
203
204 // the a/b part
205 static
206 cmsFloat64Number ab2float2(cmsUInt16Number v)
207 {
208 return ((cmsFloat64Number) v / 256.0) - 128.0;
209 }
210
211 static
212 cmsUInt16Number L2Fix2(cmsFloat64Number L)
213 {
214 return _cmsQuickSaturateWord(L * 652.8);
215 }
216
217 static
218 cmsUInt16Number ab2Fix2(cmsFloat64Number ab)
219 {
220 return _cmsQuickSaturateWord((ab + 128.0) * 256.0);
221 }
222
223
224 static
225 cmsFloat64Number L2float4(cmsUInt16Number v)
226 {
227 return (cmsFloat64Number) v / 655.35;
228 }
229
230 // the a/b part
231 static
232 cmsFloat64Number ab2float4(cmsUInt16Number v)
233 {
234 return ((cmsFloat64Number) v / 257.0) - 128.0;
235 }
236
237
238 void CMSEXPORT cmsLabEncoded2FloatV2(cmsCIELab* Lab, const cmsUInt16Number wLab[3])
239 {
240 Lab->L = L2float2(wLab[0]);
241 Lab->a = ab2float2(wLab[1]);
242 Lab->b = ab2float2(wLab[2]);
243 }
244
245
246 void CMSEXPORT cmsLabEncoded2Float(cmsCIELab* Lab, const cmsUInt16Number wLab[3])
247 {
248 Lab->L = L2float4(wLab[0]);
249 Lab->a = ab2float4(wLab[1]);
250 Lab->b = ab2float4(wLab[2]);
251 }
252
253 static
254 cmsFloat64Number Clamp_L_doubleV2(cmsFloat64Number L)
255 {
256 const cmsFloat64Number L_max = (cmsFloat64Number) (0xFFFF * 100.0) / 0xFF00;
257
258 if (L < 0) L = 0;
259 if (L > L_max) L = L_max;
260
261 return L;
262 }
263
264
265 static
266 cmsFloat64Number Clamp_ab_doubleV2(cmsFloat64Number ab)
267 {
268 if (ab < MIN_ENCODEABLE_ab2) ab = MIN_ENCODEABLE_ab2;
269 if (ab > MAX_ENCODEABLE_ab2) ab = MAX_ENCODEABLE_ab2;
270
271 return ab;
272 }
273
274 void CMSEXPORT cmsFloat2LabEncodedV2(cmsUInt16Number wLab[3], const cmsCIELab* fLab)
275 {
276 cmsCIELab Lab;
277
278 Lab.L = Clamp_L_doubleV2(fLab ->L);
279 Lab.a = Clamp_ab_doubleV2(fLab ->a);
280 Lab.b = Clamp_ab_doubleV2(fLab ->b);
281
282 wLab[0] = L2Fix2(Lab.L);
283 wLab[1] = ab2Fix2(Lab.a);
284 wLab[2] = ab2Fix2(Lab.b);
285 }
286
287
288 static
289 cmsFloat64Number Clamp_L_doubleV4(cmsFloat64Number L)
290 {
291 if (L < 0) L = 0;
292 if (L > 100.0) L = 100.0;
293
294 return L;
295 }
296
297 static
298 cmsFloat64Number Clamp_ab_doubleV4(cmsFloat64Number ab)
299 {
300 if (ab < MIN_ENCODEABLE_ab4) ab = MIN_ENCODEABLE_ab4;
301 if (ab > MAX_ENCODEABLE_ab4) ab = MAX_ENCODEABLE_ab4;
302
303 return ab;
304 }
305
306 static
307 cmsUInt16Number L2Fix4(cmsFloat64Number L)
308 {
309 return _cmsQuickSaturateWord(L * 655.35);
310 }
311
312 static
313 cmsUInt16Number ab2Fix4(cmsFloat64Number ab)
314 {
315 return _cmsQuickSaturateWord((ab + 128.0) * 257.0);
316 }
317
318 void CMSEXPORT cmsFloat2LabEncoded(cmsUInt16Number wLab[3], const cmsCIELab* fLab)
319 {
320 cmsCIELab Lab;
321
322 Lab.L = Clamp_L_doubleV4(fLab ->L);
323 Lab.a = Clamp_ab_doubleV4(fLab ->a);
324 Lab.b = Clamp_ab_doubleV4(fLab ->b);
325
326 wLab[0] = L2Fix4(Lab.L);
327 wLab[1] = ab2Fix4(Lab.a);
328 wLab[2] = ab2Fix4(Lab.b);
329 }
330
331 // Auxiliar: convert to Radians
332 static
333 cmsFloat64Number RADIANS(cmsFloat64Number deg)
334 {
335 return (deg * M_PI) / 180.;
336 }
337
338
339 // Auxiliar: atan2 but operating in degrees and returning 0 if a==b==0
340 static
341 cmsFloat64Number atan2deg(cmsFloat64Number a, cmsFloat64Number b)
342 {
343 cmsFloat64Number h;
344
345 if (a == 0 && b == 0)
346 h = 0;
347 else
348 h = atan2(a, b);
349
350 h *= (180. / M_PI);
351
352 while (h > 360.)
353 h -= 360.;
354
355 while ( h < 0)
356 h += 360.;
357
358 return h;
359 }
360
361
362 // Auxiliar: Square
363 static
364 cmsFloat64Number Sqr(cmsFloat64Number v)
365 {
366 return v * v;
367 }
368 // From cylindrical coordinates. No check is performed, then negative values are allowed
369 void CMSEXPORT cmsLab2LCh(cmsCIELCh* LCh, const cmsCIELab* Lab)
370 {
371 LCh -> L = Lab -> L;
372 LCh -> C = pow(Sqr(Lab ->a) + Sqr(Lab ->b), 0.5);
373 LCh -> h = atan2deg(Lab ->b, Lab ->a);
374 }
375
376
377 // To cylindrical coordinates. No check is performed, then negative values are allowed
378 void CMSEXPORT cmsLCh2Lab(cmsCIELab* Lab, const cmsCIELCh* LCh)
379 {
380 cmsFloat64Number h = (LCh -> h * M_PI) / 180.0;
381
382 Lab -> L = LCh -> L;
383 Lab -> a = LCh -> C * cos(h);
384 Lab -> b = LCh -> C * sin(h);
385 }
386
387 // In XYZ All 3 components are encoded using 1.15 fixed point
388 static
389 cmsUInt16Number XYZ2Fix(cmsFloat64Number d)
390 {
391 return _cmsQuickSaturateWord(d * 32768.0);
392 }
393
394 void CMSEXPORT cmsFloat2XYZEncoded(cmsUInt16Number XYZ[3], const cmsCIEXYZ* fXYZ)
395 {
396 cmsCIEXYZ xyz;
397
398 xyz.X = fXYZ -> X;
399 xyz.Y = fXYZ -> Y;
400 xyz.Z = fXYZ -> Z;
401
402 // Clamp to encodeable values.
403 if (xyz.Y <= 0) {
404
405 xyz.X = 0;
406 xyz.Y = 0;
407 xyz.Z = 0;
408 }
409
410 if (xyz.X > MAX_ENCODEABLE_XYZ)
411 xyz.X = MAX_ENCODEABLE_XYZ;
412
413 if (xyz.X < 0)
414 xyz.X = 0;
415
416 if (xyz.Y > MAX_ENCODEABLE_XYZ)
417 xyz.Y = MAX_ENCODEABLE_XYZ;
418
419 if (xyz.Y < 0)
420 xyz.Y = 0;
421
422 if (xyz.Z > MAX_ENCODEABLE_XYZ)
423 xyz.Z = MAX_ENCODEABLE_XYZ;
424
425 if (xyz.Z < 0)
426 xyz.Z = 0;
427
428
429 XYZ[0] = XYZ2Fix(xyz.X);
430 XYZ[1] = XYZ2Fix(xyz.Y);
431 XYZ[2] = XYZ2Fix(xyz.Z);
432 }
433
434
435 // To convert from Fixed 1.15 point to cmsFloat64Number
436 static
437 cmsFloat64Number XYZ2float(cmsUInt16Number v)
438 {
439 cmsS15Fixed16Number fix32;
440
441 // From 1.15 to 15.16
442 fix32 = v << 1;
443
444 // From fixed 15.16 to cmsFloat64Number
445 return _cms15Fixed16toDouble(fix32);
446 }
447
448
449 void CMSEXPORT cmsXYZEncoded2Float(cmsCIEXYZ* fXYZ, const cmsUInt16Number XYZ[3])
450 {
451 fXYZ -> X = XYZ2float(XYZ[0]);
452 fXYZ -> Y = XYZ2float(XYZ[1]);
453 fXYZ -> Z = XYZ2float(XYZ[2]);
454 }
455
456
457 // Returns dE on two Lab values
458 cmsFloat64Number CMSEXPORT cmsDeltaE(const cmsCIELab* Lab1, const cmsCIELab* Lab2)
459 {
460 cmsFloat64Number dL, da, db;
461
462 dL = fabs(Lab1 -> L - Lab2 -> L);
463 da = fabs(Lab1 -> a - Lab2 -> a);
464 db = fabs(Lab1 -> b - Lab2 -> b);
465
466 return pow(Sqr(dL) + Sqr(da) + Sqr(db), 0.5);
467 }
468
469
470 // Return the CIE94 Delta E
471 cmsFloat64Number CMSEXPORT cmsCIE94DeltaE(const cmsCIELab* Lab1, const cmsCIELab* Lab2)
472 {
473 cmsCIELCh LCh1, LCh2;
474 cmsFloat64Number dE, dL, dC, dh, dhsq;
475 cmsFloat64Number c12, sc, sh;
476
477 dL = fabs(Lab1 ->L - Lab2 ->L);
478
479 cmsLab2LCh(&LCh1, Lab1);
480 cmsLab2LCh(&LCh2, Lab2);
481
482 dC = fabs(LCh1.C - LCh2.C);
483 dE = cmsDeltaE(Lab1, Lab2);
484
485 dhsq = Sqr(dE) - Sqr(dL) - Sqr(dC);
486 if (dhsq < 0)
487 dh = 0;
488 else
489 dh = pow(dhsq, 0.5);
490
491 c12 = sqrt(LCh1.C * LCh2.C);
492
493 sc = 1.0 + (0.048 * c12);
494 sh = 1.0 + (0.014 * c12);
495
496 return sqrt(Sqr(dL) + Sqr(dC) / Sqr(sc) + Sqr(dh) / Sqr(sh));
497 }
498
499
500 // Auxiliary
501 static
502 cmsFloat64Number ComputeLBFD(const cmsCIELab* Lab)
503 {
504 cmsFloat64Number yt;
505
506 if (Lab->L > 7.996969)
507 yt = (Sqr((Lab->L+16)/116)*((Lab->L+16)/116))*100;
508 else
509 yt = 100 * (Lab->L / 903.3);
510
511 return (54.6 * (M_LOG10E * (log(yt + 1.5))) - 9.6);
512 }
513
514
515
516 // bfd - gets BFD(1:1) difference between Lab1, Lab2
517 cmsFloat64Number CMSEXPORT cmsBFDdeltaE(const cmsCIELab* Lab1, const cmsCIELab* Lab2)
518 {
519 cmsFloat64Number lbfd1,lbfd2,AveC,Aveh,dE,deltaL,
520 deltaC,deltah,dc,t,g,dh,rh,rc,rt,bfd;
521 cmsCIELCh LCh1, LCh2;
522
523
524 lbfd1 = ComputeLBFD(Lab1);
525 lbfd2 = ComputeLBFD(Lab2);
526 deltaL = lbfd2 - lbfd1;
527
528 cmsLab2LCh(&LCh1, Lab1);
529 cmsLab2LCh(&LCh2, Lab2);
530
531 deltaC = LCh2.C - LCh1.C;
532 AveC = (LCh1.C+LCh2.C)/2;
533 Aveh = (LCh1.h+LCh2.h)/2;
534
535 dE = cmsDeltaE(Lab1, Lab2);
536
537 if (Sqr(dE)>(Sqr(Lab2->L-Lab1->L)+Sqr(deltaC)))
538 deltah = sqrt(Sqr(dE)-Sqr(Lab2->L-Lab1->L)-Sqr(deltaC));
539 else
540 deltah =0;
541
542
543 dc = 0.035 * AveC / (1 + 0.00365 * AveC)+0.521;
544 g = sqrt(Sqr(Sqr(AveC))/(Sqr(Sqr(AveC))+14000));
545 t = 0.627+(0.055*cos((Aveh-254)/(180/M_PI))-
546 0.040*cos((2*Aveh-136)/(180/M_PI))+
547 0.070*cos((3*Aveh-31)/(180/M_PI))+
548 0.049*cos((4*Aveh+114)/(180/M_PI))-
549 0.015*cos((5*Aveh-103)/(180/M_PI)));
550
551 dh = dc*(g*t+1-g);
552 rh = -0.260*cos((Aveh-308)/(180/M_PI))-
553 0.379*cos((2*Aveh-160)/(180/M_PI))-
554 0.636*cos((3*Aveh+254)/(180/M_PI))+
555 0.226*cos((4*Aveh+140)/(180/M_PI))-
556 0.194*cos((5*Aveh+280)/(180/M_PI));
557
558 rc = sqrt((AveC*AveC*AveC*AveC*AveC*AveC)/((AveC*AveC*AveC*AveC*AveC*AveC)+70000000));
559 rt = rh*rc;
560
561 bfd = sqrt(Sqr(deltaL)+Sqr(deltaC/dc)+Sqr(deltah/dh)+(rt*(deltaC/dc)*(deltah/dh)));
562
563 return bfd;
564 }
565
566
567 // cmc - CMC(l:c) difference between Lab1, Lab2
568 cmsFloat64Number CMSEXPORT cmsCMCdeltaE(const cmsCIELab* Lab1, const cmsCIELab* Lab2, cmsFloat64Number l, cmsFloat64Number c)
569 {
570 cmsFloat64Number dE,dL,dC,dh,sl,sc,sh,t,f,cmc;
571 cmsCIELCh LCh1, LCh2;
572
573 if (Lab1 ->L == 0 && Lab2 ->L == 0) return 0;
574
575 cmsLab2LCh(&LCh1, Lab1);
576 cmsLab2LCh(&LCh2, Lab2);
577
578
579 dL = Lab2->L-Lab1->L;
580 dC = LCh2.C-LCh1.C;
581
582 dE = cmsDeltaE(Lab1, Lab2);
583
584 if (Sqr(dE)>(Sqr(dL)+Sqr(dC)))
585 dh = sqrt(Sqr(dE)-Sqr(dL)-Sqr(dC));
586 else
587 dh =0;
588
589 if ((LCh1.h > 164) && (LCh1.h < 345))
590 t = 0.56 + fabs(0.2 * cos(((LCh1.h + 168)/(180/M_PI))));
591 else
592 t = 0.36 + fabs(0.4 * cos(((LCh1.h + 35 )/(180/M_PI))));
593
594 sc = 0.0638 * LCh1.C / (1 + 0.0131 * LCh1.C) + 0.638;
595 sl = 0.040975 * Lab1->L /(1 + 0.01765 * Lab1->L);
596
597 if (Lab1->L<16)
598 sl = 0.511;
599
600 f = sqrt((LCh1.C * LCh1.C * LCh1.C * LCh1.C)/((LCh1.C * LCh1.C * LCh1.C * LCh1.C)+1900));
601 sh = sc*(t*f+1-f);
602 cmc = sqrt(Sqr(dL/(l*sl))+Sqr(dC/(c*sc))+Sqr(dh/sh));
603
604 return cmc;
605 }
606
607 // dE2000 The weightings KL, KC and KH can be modified to reflect the relative
608 // importance of lightness, chroma and hue in different industrial applications
609 cmsFloat64Number CMSEXPORT cmsCIE2000DeltaE(const cmsCIELab* Lab1, const cmsCIELab* Lab2,
610 cmsFloat64Number Kl, cmsFloat64Number Kc, cmsFloat64Number Kh)
611 {
612 cmsFloat64Number L1 = Lab1->L;
613 cmsFloat64Number a1 = Lab1->a;
614 cmsFloat64Number b1 = Lab1->b;
615 cmsFloat64Number C = sqrt( Sqr(a1) + Sqr(b1) );
616
617 cmsFloat64Number Ls = Lab2 ->L;
618 cmsFloat64Number as = Lab2 ->a;
619 cmsFloat64Number bs = Lab2 ->b;
620 cmsFloat64Number Cs = sqrt( Sqr(as) + Sqr(bs) );
621
622 cmsFloat64Number G = 0.5 * ( 1 - sqrt(pow((C + Cs) / 2 , 7.0) / (pow((C + Cs) / 2, 7.0) + pow(25.0, 7.0) ) ));
623
624 cmsFloat64Number a_p = (1 + G ) * a1;
625 cmsFloat64Number b_p = b1;
626 cmsFloat64Number C_p = sqrt( Sqr(a_p) + Sqr(b_p));
627 cmsFloat64Number h_p = atan2deg(b_p, a_p);
628
629
630 cmsFloat64Number a_ps = (1 + G) * as;
631 cmsFloat64Number b_ps = bs;
632 cmsFloat64Number C_ps = sqrt(Sqr(a_ps) + Sqr(b_ps));
633 cmsFloat64Number h_ps = atan2deg(b_ps, a_ps);
634
635 cmsFloat64Number meanC_p =(C_p + C_ps) / 2;
636
637 cmsFloat64Number hps_plus_hp = h_ps + h_p;
638 cmsFloat64Number hps_minus_hp = h_ps - h_p;
639
640 cmsFloat64Number meanh_p = fabs(hps_minus_hp) <= 180.000001 ? (hps_plus_hp)/2 :
641 (hps_plus_hp) < 360 ? (hps_plus_hp + 360)/2 :
642 (hps_plus_hp - 360)/2;
643
644 cmsFloat64Number delta_h = (hps_minus_hp) <= -180.000001 ? (hps_minus_hp + 360) :
645 (hps_minus_hp) > 180 ? (hps_minus_hp - 360) :
646 (hps_minus_hp);
647 cmsFloat64Number delta_L = (Ls - L1);
648 cmsFloat64Number delta_C = (C_ps - C_p );
649
650
651 cmsFloat64Number delta_H =2 * sqrt(C_ps*C_p) * sin(RADIANS(delta_h) / 2);
652
653 cmsFloat64Number T = 1 - 0.17 * cos(RADIANS(meanh_p-30))
654 + 0.24 * cos(RADIANS(2*meanh_p))
655 + 0.32 * cos(RADIANS(3*meanh_p + 6))
656 - 0.2 * cos(RADIANS(4*meanh_p - 63));
657
658 cmsFloat64Number Sl = 1 + (0.015 * Sqr((Ls + L1) /2- 50) )/ sqrt(20 + Sqr( (Ls+L1)/2 - 50) );
659
660 cmsFloat64Number Sc = 1 + 0.045 * (C_p + C_ps)/2;
661 cmsFloat64Number Sh = 1 + 0.015 * ((C_ps + C_p)/2) * T;
662
663 cmsFloat64Number delta_ro = 30 * exp( -Sqr(((meanh_p - 275 ) / 25)));
664
665 cmsFloat64Number Rc = 2 * sqrt(( pow(meanC_p, 7.0) )/( pow(meanC_p, 7.0) + pow(25.0, 7.0)));
666
667 cmsFloat64Number Rt = -sin(2 * RADIANS(delta_ro)) * Rc;
668
669 cmsFloat64Number deltaE00 = sqrt( Sqr(delta_L /(Sl * Kl)) +
670 Sqr(delta_C/(Sc * Kc)) +
671 Sqr(delta_H/(Sh * Kh)) +
672 Rt*(delta_C/(Sc * Kc)) * (delta_H / (Sh * Kh)));
673
674 return deltaE00;
675 }
676
677 // This function returns a number of gridpoints to be used as LUT table. It assumes same number
678 // of gripdpoints in all dimensions. Flags may override the choice.
679 int _cmsReasonableGridpointsByColorspace(cmsColorSpaceSignature Colorspace, cmsUInt32Number dwFlags)
680 {
681 int nChannels;
682
683 // Already specified?
684 if (dwFlags & 0x00FF0000) {
685 // Yes, grab'em
686 return (dwFlags >> 16) & 0xFF;
687 }
688
689 nChannels = cmsChannelsOf(Colorspace);
690
691 // HighResPrecalc is maximum resolution
692 if (dwFlags & cmsFLAGS_HIGHRESPRECALC) {
693
694 if (nChannels > 4)
695 return 7; // 7 for Hifi
696
697 if (nChannels == 4) // 23 for CMYK
698 return 23;
699
700 return 49; // 49 for RGB and others
701 }
702
703
704 // LowResPrecal is lower resolution
705 if (dwFlags & cmsFLAGS_LOWRESPRECALC) {
706
707 if (nChannels > 4)
708 return 6; // 6 for more than 4 channels
709
710 if (nChannels == 1)
711 return 33; // For monochrome
712
713 return 17; // 17 for remaining
714 }
715
716 // Default values
717 if (nChannels > 4)
718 return 7; // 7 for Hifi
719
720 if (nChannels == 4)
721 return 17; // 17 for CMYK
722
723 return 33; // 33 for RGB
724 }
725
726
727 cmsBool _cmsEndPointsBySpace(cmsColorSpaceSignature Space,
728 cmsUInt16Number **White,
729 cmsUInt16Number **Black,
730 cmsUInt32Number *nOutputs)
731 {
732 // Only most common spaces
733
734 static cmsUInt16Number RGBblack[4] = { 0, 0, 0 };
735 static cmsUInt16Number RGBwhite[4] = { 0xffff, 0xffff, 0xffff };
736 static cmsUInt16Number CMYKblack[4] = { 0xffff, 0xffff, 0xffff, 0xffff }; // 400% of ink
737 static cmsUInt16Number CMYKwhite[4] = { 0, 0, 0, 0 };
738 static cmsUInt16Number LABblack[4] = { 0, 0x8080, 0x8080 }; // V4 Lab encoding
739 static cmsUInt16Number LABwhite[4] = { 0xFFFF, 0x8080, 0x8080 };
740 static cmsUInt16Number CMYblack[4] = { 0xffff, 0xffff, 0xffff };
741 static cmsUInt16Number CMYwhite[4] = { 0, 0, 0 };
742 static cmsUInt16Number Grayblack[4] = { 0 };
743 static cmsUInt16Number GrayWhite[4] = { 0xffff };
744
745 switch (Space) {
746
747 case cmsSigGrayData: if (White) *White = GrayWhite;
748 if (Black) *Black = Grayblack;
749 if (nOutputs) *nOutputs = 1;
750 return TRUE;
751
752 case cmsSigRgbData: if (White) *White = RGBwhite;
753 if (Black) *Black = RGBblack;
754 if (nOutputs) *nOutputs = 3;
755 return TRUE;
756
757 case cmsSigLabData: if (White) *White = LABwhite;
758 if (Black) *Black = LABblack;
759 if (nOutputs) *nOutputs = 3;
760 return TRUE;
761
762 case cmsSigCmykData: if (White) *White = CMYKwhite;
763 if (Black) *Black = CMYKblack;
764 if (nOutputs) *nOutputs = 4;
765 return TRUE;
766
767 case cmsSigCmyData: if (White) *White = CMYwhite;
768 if (Black) *Black = CMYblack;
769 if (nOutputs) *nOutputs = 3;
770 return TRUE;
771
772 default:;
773 }
774
775 return FALSE;
776 }
777
778
779
780 // Several utilities -------------------------------------------------------
781
782 // Translate from our colorspace to ICC representation
783
784 cmsColorSpaceSignature CMSEXPORT _cmsICCcolorSpace(int OurNotation)
785 {
786 switch (OurNotation) {
787
788 case 1:
789 case PT_GRAY: return cmsSigGrayData;
790
791 case 2:
792 case PT_RGB: return cmsSigRgbData;
793
794 case PT_CMY: return cmsSigCmyData;
795 case PT_CMYK: return cmsSigCmykData;
796 case PT_YCbCr:return cmsSigYCbCrData;
797 case PT_YUV: return cmsSigLuvData;
798 case PT_XYZ: return cmsSigXYZData;
799
800 case PT_LabV2:
801 case PT_Lab: return cmsSigLabData;
802
803 case PT_YUVK: return cmsSigLuvKData;
804 case PT_HSV: return cmsSigHsvData;
805 case PT_HLS: return cmsSigHlsData;
806 case PT_Yxy: return cmsSigYxyData;
807
808 case PT_MCH1: return cmsSigMCH1Data;
809 case PT_MCH2: return cmsSigMCH2Data;
810 case PT_MCH3: return cmsSigMCH3Data;
811 case PT_MCH4: return cmsSigMCH4Data;
812 case PT_MCH5: return cmsSigMCH5Data;
813 case PT_MCH6: return cmsSigMCH6Data;
814 case PT_MCH7: return cmsSigMCH7Data;
815 case PT_MCH8: return cmsSigMCH8Data;
816
817 case PT_MCH9: return cmsSigMCH9Data;
818 case PT_MCH10: return cmsSigMCHAData;
819 case PT_MCH11: return cmsSigMCHBData;
820 case PT_MCH12: return cmsSigMCHCData;
821 case PT_MCH13: return cmsSigMCHDData;
822 case PT_MCH14: return cmsSigMCHEData;
823 case PT_MCH15: return cmsSigMCHFData;
824
825 default: return (cmsColorSpaceSignature) (-1);
826 }
827 }
828
829
830 int CMSEXPORT _cmsLCMScolorSpace(cmsColorSpaceSignature ProfileSpace)
831 {
832 switch (ProfileSpace) {
833
834 case cmsSigGrayData: return PT_GRAY;
835 case cmsSigRgbData: return PT_RGB;
836 case cmsSigCmyData: return PT_CMY;
837 case cmsSigCmykData: return PT_CMYK;
838 case cmsSigYCbCrData:return PT_YCbCr;
839 case cmsSigLuvData: return PT_YUV;
840 case cmsSigXYZData: return PT_XYZ;
841 case cmsSigLabData: return PT_Lab;
842 case cmsSigLuvKData: return PT_YUVK;
843 case cmsSigHsvData: return PT_HSV;
844 case cmsSigHlsData: return PT_HLS;
845 case cmsSigYxyData: return PT_Yxy;
846
847 case cmsSig1colorData:
848 case cmsSigMCH1Data: return PT_MCH1;
849
850 case cmsSig2colorData:
851 case cmsSigMCH2Data: return PT_MCH2;
852
853 case cmsSig3colorData:
854 case cmsSigMCH3Data: return PT_MCH3;
855
856 case cmsSig4colorData:
857 case cmsSigMCH4Data: return PT_MCH4;
858
859 case cmsSig5colorData:
860 case cmsSigMCH5Data: return PT_MCH5;
861
862 case cmsSig6colorData:
863 case cmsSigMCH6Data: return PT_MCH6;
864
865 case cmsSigMCH7Data:
866 case cmsSig7colorData:return PT_MCH7;
867
868 case cmsSigMCH8Data:
869 case cmsSig8colorData:return PT_MCH8;
870
871 case cmsSigMCH9Data:
872 case cmsSig9colorData:return PT_MCH9;
873
874 case cmsSigMCHAData:
875 case cmsSig10colorData:return PT_MCH10;
876
877 case cmsSigMCHBData:
878 case cmsSig11colorData:return PT_MCH11;
879
880 case cmsSigMCHCData:
881 case cmsSig12colorData:return PT_MCH12;
882
883 case cmsSigMCHDData:
884 case cmsSig13colorData:return PT_MCH13;
885
886 case cmsSigMCHEData:
887 case cmsSig14colorData:return PT_MCH14;
888
889 case cmsSigMCHFData:
890 case cmsSig15colorData:return PT_MCH15;
891
892 default: return (cmsColorSpaceSignature) (-1);
893 }
894 }
895
896
897 cmsUInt32Number CMSEXPORT cmsChannelsOf(cmsColorSpaceSignature ColorSpace)
898 {
899 switch (ColorSpace) {
900
901 case cmsSig1colorData:
902 case cmsSigGrayData: return 1;
903
904 case cmsSig2colorData: return 2;
905
906 case cmsSigXYZData:
907 case cmsSigLabData:
908 case cmsSigLuvData:
909 case cmsSigYCbCrData:
910 case cmsSigYxyData:
911 case cmsSigRgbData:
912 case cmsSigHsvData:
913 case cmsSigHlsData:
914 case cmsSigCmyData:
915 case cmsSig3colorData: return 3;
916
917 case cmsSigLuvKData:
918 case cmsSigCmykData:
919 case cmsSig4colorData: return 4;
920
921 case cmsSigMCH5Data:
922 case cmsSig5colorData: return 5;
923
924 case cmsSigMCH6Data:
925 case cmsSig6colorData: return 6;
926
927 case cmsSigMCH7Data:
928 case cmsSig7colorData: return 7;
929
930 case cmsSigMCH8Data:
931 case cmsSig8colorData: return 8;
932
933 case cmsSigMCH9Data:
934 case cmsSig9colorData: return 9;
935
936 case cmsSigMCHAData:
937 case cmsSig10colorData: return 10;
938
939 case cmsSigMCHBData:
940 case cmsSig11colorData: return 11;
941
942 case cmsSigMCHCData:
943 case cmsSig12colorData: return 12;
944
945 case cmsSigMCHDData:
946 case cmsSig13colorData: return 13;
947
948 case cmsSigMCHEData:
949 case cmsSig14colorData: return 14;
950
951 case cmsSigMCHFData:
952 case cmsSig15colorData: return 15;
953
954 default: return 3;
955 }
956 }