//--------------------------------------------------------------------------------- // // Little Color Management System // Copyright (c) 1998-2017 Marti Maria Saguer // // Permission is hereby granted, free of charge, to any person obtaining // a copy of this software and associated documentation files (the "Software"), // to deal in the Software without restriction, including without limitation // the rights to use, copy, modify, merge, publish, distribute, sublicense, // and/or sell copies of the Software, and to permit persons to whom the Software // is furnished to do so, subject to the following conditions: // // The above copyright notice and this permission notice shall be included in // all copies or substantial portions of the Software. // // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO // THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. // //--------------------------------------------------------------------------------- // #include "lcms2_internal.h" // CIECAM 02 appearance model. Many thanks to Jordi Vilar for the debugging. // ---------- Implementation -------------------------------------------- typedef struct { cmsFloat64Number XYZ[3]; cmsFloat64Number RGB[3]; cmsFloat64Number RGBc[3]; cmsFloat64Number RGBp[3]; cmsFloat64Number RGBpa[3]; cmsFloat64Number a, b, h, e, H, A, J, Q, s, t, C, M; cmsFloat64Number abC[2]; cmsFloat64Number abs[2]; cmsFloat64Number abM[2]; } CAM02COLOR; typedef struct { CAM02COLOR adoptedWhite; cmsFloat64Number LA, Yb; cmsFloat64Number F, c, Nc; cmsUInt32Number surround; cmsFloat64Number n, Nbb, Ncb, z, FL, D; cmsContext ContextID; } cmsCIECAM02; static cmsFloat64Number compute_n(cmsCIECAM02* pMod) { return (pMod -> Yb / pMod -> adoptedWhite.XYZ[1]); } static cmsFloat64Number compute_z(cmsCIECAM02* pMod) { return (1.48 + pow(pMod -> n, 0.5)); } static cmsFloat64Number computeNbb(cmsCIECAM02* pMod) { return (0.725 * pow((1.0 / pMod -> n), 0.2)); } static cmsFloat64Number computeFL(cmsCIECAM02* pMod) { cmsFloat64Number k, FL; k = 1.0 / ((5.0 * pMod->LA) + 1.0); FL = 0.2 * pow(k, 4.0) * (5.0 * pMod->LA) + 0.1 * (pow((1.0 - pow(k, 4.0)), 2.0)) * (pow((5.0 * pMod->LA), (1.0 / 3.0))); return FL; } static cmsFloat64Number computeD(cmsCIECAM02* pMod) { cmsFloat64Number D; D = pMod->F - (1.0/3.6)*(exp(((-pMod ->LA-42) / 92.0))); return D; } static CAM02COLOR XYZtoCAT02(CAM02COLOR clr) { clr.RGB[0] = (clr.XYZ[0] * 0.7328) + (clr.XYZ[1] * 0.4296) + (clr.XYZ[2] * -0.1624); clr.RGB[1] = (clr.XYZ[0] * -0.7036) + (clr.XYZ[1] * 1.6975) + (clr.XYZ[2] * 0.0061); clr.RGB[2] = (clr.XYZ[0] * 0.0030) + (clr.XYZ[1] * 0.0136) + (clr.XYZ[2] * 0.9834); return clr; } static CAM02COLOR ChromaticAdaptation(CAM02COLOR clr, cmsCIECAM02* pMod) { cmsUInt32Number i; for (i = 0; i < 3; i++) { clr.RGBc[i] = ((pMod -> adoptedWhite.XYZ[1] * (pMod->D / pMod -> adoptedWhite.RGB[i])) + (1.0 - pMod->D)) * clr.RGB[i]; } return clr; } static CAM02COLOR CAT02toHPE(CAM02COLOR clr) { cmsFloat64Number M[9]; M[0] =(( 0.38971 * 1.096124) + (0.68898 * 0.454369) + (-0.07868 * -0.009628)); M[1] =(( 0.38971 * -0.278869) + (0.68898 * 0.473533) + (-0.07868 * -0.005698)); M[2] =(( 0.38971 * 0.182745) + (0.68898 * 0.072098) + (-0.07868 * 1.015326)); M[3] =((-0.22981 * 1.096124) + (1.18340 * 0.454369) + ( 0.04641 * -0.009628)); M[4] =((-0.22981 * -0.278869) + (1.18340 * 0.473533) + ( 0.04641 * -0.005698)); M[5] =((-0.22981 * 0.182745) + (1.18340 * 0.072098) + ( 0.04641 * 1.015326)); M[6] =(-0.009628); M[7] =(-0.005698); M[8] =( 1.015326); clr.RGBp[0] = (clr.RGBc[0] * M[0]) + (clr.RGBc[1] * M[1]) + (clr.RGBc[2] * M[2]); clr.RGBp[1] = (clr.RGBc[0] * M[3]) + (clr.RGBc[1] * M[4]) + (clr.RGBc[2] * M[5]); clr.RGBp[2] = (clr.RGBc[0] * M[6]) + (clr.RGBc[1] * M[7]) + (clr.RGBc[2] * M[8]); return clr; } static CAM02COLOR NonlinearCompression(CAM02COLOR clr, cmsCIECAM02* pMod) { cmsUInt32Number i; cmsFloat64Number temp; for (i = 0; i < 3; i++) { if (clr.RGBp[i] < 0) { temp = pow((-1.0 * pMod->FL * clr.RGBp[i] / 100.0), 0.42); clr.RGBpa[i] = (-1.0 * 400.0 * temp) / (temp + 27.13) + 0.1; } else { temp = pow((pMod->FL * clr.RGBp[i] / 100.0), 0.42); clr.RGBpa[i] = (400.0 * temp) / (temp + 27.13) + 0.1; } } clr.A = (((2.0 * clr.RGBpa[0]) + clr.RGBpa[1] + (clr.RGBpa[2] / 20.0)) - 0.305) * pMod->Nbb; return clr; } static CAM02COLOR ComputeCorrelates(CAM02COLOR clr, cmsCIECAM02* pMod) { cmsFloat64Number a, b, temp, e, t, r2d, d2r; a = clr.RGBpa[0] - (12.0 * clr.RGBpa[1] / 11.0) + (clr.RGBpa[2] / 11.0); b = (clr.RGBpa[0] + clr.RGBpa[1] - (2.0 * clr.RGBpa[2])) / 9.0; r2d = (180.0 / 3.141592654); if (a == 0) { if (b == 0) clr.h = 0; else if (b > 0) clr.h = 90; else clr.h = 270; } else if (a > 0) { temp = b / a; if (b > 0) clr.h = (r2d * atan(temp)); else if (b == 0) clr.h = 0; else clr.h = (r2d * atan(temp)) + 360; } else { temp = b / a; clr.h = (r2d * atan(temp)) + 180; } d2r = (3.141592654 / 180.0); e = ((12500.0 / 13.0) * pMod->Nc * pMod->Ncb) * (cos((clr.h * d2r + 2.0)) + 3.8); if (clr.h < 20.14) { temp = ((clr.h + 122.47)/1.2) + ((20.14 - clr.h)/0.8); clr.H = 300 + (100*((clr.h + 122.47)/1.2)) / temp; } else if (clr.h < 90.0) { temp = ((clr.h - 20.14)/0.8) + ((90.00 - clr.h)/0.7); clr.H = (100*((clr.h - 20.14)/0.8)) / temp; } else if (clr.h < 164.25) { temp = ((clr.h - 90.00)/0.7) + ((164.25 - clr.h)/1.0); clr.H = 100 + ((100*((clr.h - 90.00)/0.7)) / temp); } else if (clr.h < 237.53) { temp = ((clr.h - 164.25)/1.0) + ((237.53 - clr.h)/1.2); clr.H = 200 + ((100*((clr.h - 164.25)/1.0)) / temp); } else { temp = ((clr.h - 237.53)/1.2) + ((360 - clr.h + 20.14)/0.8); clr.H = 300 + ((100*((clr.h - 237.53)/1.2)) / temp); } clr.J = 100.0 * pow((clr.A / pMod->adoptedWhite.A), (pMod->c * pMod->z)); clr.Q = (4.0 / pMod->c) * pow((clr.J / 100.0), 0.5) * (pMod->adoptedWhite.A + 4.0) * pow(pMod->FL, 0.25); t = (e * pow(((a * a) + (b * b)), 0.5)) / (clr.RGBpa[0] + clr.RGBpa[1] + ((21.0 / 20.0) * clr.RGBpa[2])); clr.C = pow(t, 0.9) * pow((clr.J / 100.0), 0.5) * pow((1.64 - pow(0.29, pMod->n)), 0.73); clr.M = clr.C * pow(pMod->FL, 0.25); clr.s = 100.0 * pow((clr.M / clr.Q), 0.5); return clr; } static CAM02COLOR InverseCorrelates(CAM02COLOR clr, cmsCIECAM02* pMod) { cmsFloat64Number t, e, p1, p2, p3, p4, p5, hr, d2r; d2r = 3.141592654 / 180.0; t = pow( (clr.C / (pow((clr.J / 100.0), 0.5) * (pow((1.64 - pow(0.29, pMod->n)), 0.73)))), (1.0 / 0.9) ); e = ((12500.0 / 13.0) * pMod->Nc * pMod->Ncb) * (cos((clr.h * d2r + 2.0)) + 3.8); clr.A = pMod->adoptedWhite.A * pow( (clr.J / 100.0), (1.0 / (pMod->c * pMod->z))); p1 = e / t; p2 = (clr.A / pMod->Nbb) + 0.305; p3 = 21.0 / 20.0; hr = clr.h * d2r; if (fabs(sin(hr)) >= fabs(cos(hr))) { p4 = p1 / sin(hr); clr.b = (p2 * (2.0 + p3) * (460.0 / 1403.0)) / (p4 + (2.0 + p3) * (220.0 / 1403.0) * (cos(hr) / sin(hr)) - (27.0 / 1403.0) + p3 * (6300.0 / 1403.0)); clr.a = clr.b * (cos(hr) / sin(hr)); } else { p5 = p1 / cos(hr); clr.a = (p2 * (2.0 + p3) * (460.0 / 1403.0)) / (p5 + (2.0 + p3) * (220.0 / 1403.0) - ((27.0 / 1403.0) - p3 * (6300.0 / 1403.0)) * (sin(hr) / cos(hr))); clr.b = clr.a * (sin(hr) / cos(hr)); } clr.RGBpa[0] = ((460.0 / 1403.0) * p2) + ((451.0 / 1403.0) * clr.a) + ((288.0 / 1403.0) * clr.b); clr.RGBpa[1] = ((460.0 / 1403.0) * p2) - ((891.0 / 1403.0) * clr.a) - ((261.0 / 1403.0) * clr.b); clr.RGBpa[2] = ((460.0 / 1403.0) * p2) - ((220.0 / 1403.0) * clr.a) - ((6300.0 / 1403.0) * clr.b); return clr; } static CAM02COLOR InverseNonlinearity(CAM02COLOR clr, cmsCIECAM02* pMod) { cmsUInt32Number i; cmsFloat64Number c1; for (i = 0; i < 3; i++) { if ((clr.RGBpa[i] - 0.1) < 0) c1 = -1; else c1 = 1; clr.RGBp[i] = c1 * (100.0 / pMod->FL) * pow(((27.13 * fabs(clr.RGBpa[i] - 0.1)) / (400.0 - fabs(clr.RGBpa[i] - 0.1))), (1.0 / 0.42)); } return clr; } static CAM02COLOR HPEtoCAT02(CAM02COLOR clr) { cmsFloat64Number M[9]; M[0] = (( 0.7328 * 1.910197) + (0.4296 * 0.370950)); M[1] = (( 0.7328 * -1.112124) + (0.4296 * 0.629054)); M[2] = (( 0.7328 * 0.201908) + (0.4296 * 0.000008) - 0.1624); M[3] = ((-0.7036 * 1.910197) + (1.6975 * 0.370950)); M[4] = ((-0.7036 * -1.112124) + (1.6975 * 0.629054)); M[5] = ((-0.7036 * 0.201908) + (1.6975 * 0.000008) + 0.0061); M[6] = (( 0.0030 * 1.910197) + (0.0136 * 0.370950)); M[7] = (( 0.0030 * -1.112124) + (0.0136 * 0.629054)); M[8] = (( 0.0030 * 0.201908) + (0.0136 * 0.000008) + 0.9834);; clr.RGBc[0] = (clr.RGBp[0] * M[0]) + (clr.RGBp[1] * M[1]) + (clr.RGBp[2] * M[2]); clr.RGBc[1] = (clr.RGBp[0] * M[3]) + (clr.RGBp[1] * M[4]) + (clr.RGBp[2] * M[5]); clr.RGBc[2] = (clr.RGBp[0] * M[6]) + (clr.RGBp[1] * M[7]) + (clr.RGBp[2] * M[8]); return clr; } static CAM02COLOR InverseChromaticAdaptation(CAM02COLOR clr, cmsCIECAM02* pMod) { cmsUInt32Number i; for (i = 0; i < 3; i++) { clr.RGB[i] = clr.RGBc[i] / ((pMod->adoptedWhite.XYZ[1] * pMod->D / pMod->adoptedWhite.RGB[i]) + 1.0 - pMod->D); } return clr; } static CAM02COLOR CAT02toXYZ(CAM02COLOR clr) { clr.XYZ[0] = (clr.RGB[0] * 1.096124) + (clr.RGB[1] * -0.278869) + (clr.RGB[2] * 0.182745); clr.XYZ[1] = (clr.RGB[0] * 0.454369) + (clr.RGB[1] * 0.473533) + (clr.RGB[2] * 0.072098); clr.XYZ[2] = (clr.RGB[0] * -0.009628) + (clr.RGB[1] * -0.005698) + (clr.RGB[2] * 1.015326); return clr; } cmsHANDLE CMSEXPORT cmsCIECAM02Init(cmsContext ContextID, const cmsViewingConditions* pVC) { cmsCIECAM02* lpMod; _cmsAssert(pVC != NULL); if((lpMod = (cmsCIECAM02*) _cmsMallocZero(ContextID, sizeof(cmsCIECAM02))) == NULL) { return NULL; } lpMod ->ContextID = ContextID; lpMod ->adoptedWhite.XYZ[0] = pVC ->whitePoint.X; lpMod ->adoptedWhite.XYZ[1] = pVC ->whitePoint.Y; lpMod ->adoptedWhite.XYZ[2] = pVC ->whitePoint.Z; lpMod -> LA = pVC ->La; lpMod -> Yb = pVC ->Yb; lpMod -> D = pVC ->D_value; lpMod -> surround = pVC ->surround; switch (lpMod -> surround) { case CUTSHEET_SURROUND: lpMod->F = 0.8; lpMod->c = 0.41; lpMod->Nc = 0.8; break; case DARK_SURROUND: lpMod -> F = 0.8; lpMod -> c = 0.525; lpMod -> Nc = 0.8; break; case DIM_SURROUND: lpMod -> F = 0.9; lpMod -> c = 0.59; lpMod -> Nc = 0.95; break; default: // Average surround lpMod -> F = 1.0; lpMod -> c = 0.69; lpMod -> Nc = 1.0; } lpMod -> n = compute_n(lpMod); lpMod -> z = compute_z(lpMod); lpMod -> Nbb = computeNbb(lpMod); lpMod -> FL = computeFL(lpMod); if (lpMod -> D == D_CALCULATE) { lpMod -> D = computeD(lpMod); } lpMod -> Ncb = lpMod -> Nbb; lpMod -> adoptedWhite = XYZtoCAT02(lpMod -> adoptedWhite); lpMod -> adoptedWhite = ChromaticAdaptation(lpMod -> adoptedWhite, lpMod); lpMod -> adoptedWhite = CAT02toHPE(lpMod -> adoptedWhite); lpMod -> adoptedWhite = NonlinearCompression(lpMod -> adoptedWhite, lpMod); return (cmsHANDLE) lpMod; } void CMSEXPORT cmsCIECAM02Done(cmsHANDLE hModel) { cmsCIECAM02* lpMod = (cmsCIECAM02*) hModel; if (lpMod) _cmsFree(lpMod ->ContextID, lpMod); } void CMSEXPORT cmsCIECAM02Forward(cmsHANDLE hModel, const cmsCIEXYZ* pIn, cmsJCh* pOut) { CAM02COLOR clr; cmsCIECAM02* lpMod = (cmsCIECAM02*) hModel; _cmsAssert(lpMod != NULL); _cmsAssert(pIn != NULL); _cmsAssert(pOut != NULL); memset(&clr, 0, sizeof(clr)); clr.XYZ[0] = pIn ->X; clr.XYZ[1] = pIn ->Y; clr.XYZ[2] = pIn ->Z; clr = XYZtoCAT02(clr); clr = ChromaticAdaptation(clr, lpMod); clr = CAT02toHPE(clr); clr = NonlinearCompression(clr, lpMod); clr = ComputeCorrelates(clr, lpMod); pOut ->J = clr.J; pOut ->C = clr.C; pOut ->h = clr.h; } void CMSEXPORT cmsCIECAM02Reverse(cmsHANDLE hModel, const cmsJCh* pIn, cmsCIEXYZ* pOut) { CAM02COLOR clr; cmsCIECAM02* lpMod = (cmsCIECAM02*) hModel; _cmsAssert(lpMod != NULL); _cmsAssert(pIn != NULL); _cmsAssert(pOut != NULL); memset(&clr, 0, sizeof(clr)); clr.J = pIn -> J; clr.C = pIn -> C; clr.h = pIn -> h; clr = InverseCorrelates(clr, lpMod); clr = InverseNonlinearity(clr, lpMod); clr = HPEtoCAT02(clr); clr = InverseChromaticAdaptation(clr, lpMod); clr = CAT02toXYZ(clr); pOut ->X = clr.XYZ[0]; pOut ->Y = clr.XYZ[1]; pOut ->Z = clr.XYZ[2]; }