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 61 cmsFloat64Number compute_n(cmsCIECAM02* pMod) 62 { 63 return (pMod -> Yb / pMod -> adoptedWhite.XYZ[1]); 64 } 65 66 static 67 cmsFloat64Number compute_z(cmsCIECAM02* pMod) 68 { 69 return (1.48 + pow(pMod -> n, 0.5)); 70 } 71 72 static 73 cmsFloat64Number computeNbb(cmsCIECAM02* pMod) 74 { 75 return (0.725 * pow((1.0 / pMod -> n), 0.2)); 76 } 77 78 static 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 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 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 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 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 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 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 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 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 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 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 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 } 357 358 359 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 } 427 428 void CMSEXPORT cmsCIECAM02Done(cmsHANDLE hModel) 429 { 430 cmsCIECAM02* lpMod = (cmsCIECAM02*) hModel; 431 432 if (lpMod) _cmsFree(lpMod ->ContextID, lpMod); 433 } 434 435 436 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 } 461 462 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
