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diff --git a/xicc/cam97s3.c b/xicc/cam97s3.c
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+
+/*
+ * cam97s3hk
+ *
+ * Color Appearance Model, based on
+ * CIECAM97, "Revision for Practical Applications"
+ * by Mark D. Fairchild, with the addition of the Viewing Flare
+ * model described on page 487 of "Digital Color Management",
+ * by Edward Giorgianni and Thomas Madden, and the
+ * Helmholtz-Kohlraush effect, using the equation
+ * the Bradford-Hunt 96C model as detailed in Mark Fairchilds
+ * book "Color Appearance Models".
+ *
+ * Author: Graeme W. Gill
+ * Date: 5/10/00
+ * Version: 1.20
+ *
+ * Copyright 2000, 2002 Graeme W. Gill
+ * Please refer to COPYRIGHT file for details.
+ * This material is licenced under the GNU AFFERO GENERAL PUBLIC LICENSE Version 3 :-
+ * see the License.txt file for licencing details.
+ */
+
+/* Note that XYZ values are normalised to 1.0 consistent */
+/* with the ICC convention (not 100.0 as assumed by the CIECAM spec.) */
+/* Note that all whites are assumed to be normalised (ie. Y = 1.0) */
+
+/* Various changes have been made to allow the CAM conversions to */
+/* function over a much greater range of XYZ and Jab values that */
+/* the functions are described in the above references. This is */
+/* because such values arise in the process of gamut mapping, and */
+/* in scanning through the grid of PCS values needed to fill in */
+/* the A2B table of an ICC profile. Such values have no correlation */
+/* to a real color value, but none the less need to be handled without */
+/* causing an exception, in a geometrically consistent and reversible */
+/* fashion. */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include "xcam.h"
+#include "cam97s3.h"
+
+#undef DIAG /* Print internal value diagnostics for each conversion */
+
+#define CAM_PI 3.14159265359
+
+/* Utility function */
+/* Return a viewing condition enumeration from the given Ambient and */
+/* Adapting/Surround Luminance. */
+static ViewingCondition cam97_Ambient2VC(
+double La, /* Ambient Luminance (cd/m^2) */
+double Lv /* Luminance of white in the Viewing/Scene/Image field (cd/m^2) */
+) {
+ double r;
+
+ if (fabs(La) < 1e-10) /* Hmm. */
+ r = 1.0;
+ else
+ r = La/Lv;
+
+ if (r < 0.01)
+ return vc_dark;
+ if (r < 0.2)
+ return vc_dim;
+ return vc_average;
+}
+
+static void cam_free(cam97s3 *s);
+static int set_view(struct _cam97s3 *s, ViewingCondition Ev, double Wxyz[3],
+ double La, double Yb, double Lv, double Yf, double Fxyz[3],
+ int hk);
+static int XYZ_to_cam(struct _cam97s3 *s, double *Jab, double *xyz);
+static int cam_to_XYZ(struct _cam97s3 *s, double *xyz, double *Jab);
+
+/* Create a cam97s3 conversion object, with default viewing conditions */
+cam97s3 *new_cam97s3(void) {
+ cam97s3 *s;
+// double D50[3] = { 0.9642, 1.0000, 0.8249 };
+
+ if ((s = (cam97s3 *)calloc(1, sizeof(cam97s3))) == NULL) {
+ fprintf(stderr,"cam97s3: malloc failed allocating object\n");
+ exit(-1);
+ }
+
+ /* Initialise methods */
+ s->del = cam_free;
+ s->set_view = set_view;
+ s->XYZ_to_cam = XYZ_to_cam;
+ s->cam_to_XYZ = cam_to_XYZ;
+
+ /* Set a default viewing condition ?? */
+ /* set_view(s, vc_average, D50, 33.0, 0.2, 0.0, 0.0, D50, 0); */
+
+ return s;
+}
+
+static void cam_free(cam97s3 *s) {
+ if (s != NULL)
+ free(s);
+}
+
+/* A version of the pow() function that preserves the */
+/* sign of its first argument. */
+static double spow(double x, double y) {
+ return x < 0.0 ? -pow(-x,y) : pow(x,y);
+}
+
+static int set_view(
+cam97s3 *s,
+ViewingCondition Ev, /* Enumerated Viewing Condition */
+double Wxyz[3], /* Reference/Adapted White XYZ (Y range 0.0 .. 1.0) */
+double La, /* Adapting/Surround Luminance cd/m^2 */
+double Yb, /* Relative Luminance of Background to reference white */
+double Lv, /* Luminance of white in the Viewing/Scene/Image field (cd/m^2) */
+ /* Ignored if Ev is set to other than vc_none */
+double Yf, /* Flare as a fraction of the reference white (Y range 0.0 .. 1.0) */
+double Fxyz[3], /* The Flare white coordinates (typically the Ambient color) */
+int hk /* Flag, NZ to use Helmholtz-Kohlraush effect */
+) {
+ double tt;
+
+ if (Ev == vc_none) /* Compute enumerated viewing condition */
+ Ev = cam97_Ambient2VC(La, Lv);
+ /* Transfer parameters to the object */
+ s->Ev = Ev;
+ s->Wxyz[0] = Wxyz[0];
+ s->Wxyz[1] = Wxyz[1];
+ s->Wxyz[2] = Wxyz[2];
+ s->Yb = Yb > 0.005 ? Yb : 0.005; /* Set minimum to avoid divide by 0.0 */
+ s->La = La;
+ s->Yf = Yf;
+ s->Fxyz[0] = Fxyz[0];
+ s->Fxyz[1] = Fxyz[1];
+ s->Fxyz[2] = Fxyz[2];
+ s->hk = hk;
+
+ /* Compute the internal parameters by category */
+ switch(s->Ev) {
+ case vc_dark:
+ s->C = 0.525;
+ s->Nc = 0.8;
+ s->F = 0.9;
+ break;
+ case vc_dim:
+ s->C = 0.59;
+ s->Nc = 0.95;
+ s->F = 0.9;
+ break;
+ case vc_cut_sheet:
+ s->C = 0.41;
+ s->Nc = 0.8;
+ s->F = 0.9;
+ break;
+ default: /* average */
+ s->C = 0.69;
+ s->Nc = 1.0;
+ s->F = 1.0;
+ break;
+ }
+
+ /* Compute values that only change with viewing parameters */
+
+ /* Figure out the Flare contribution to the flareless XYZ input */
+ tt = s->Yf * s->Wxyz[1]/s->Fxyz[1];
+ s->Fsxyz[0] = tt * s->Fxyz[0];
+ s->Fsxyz[1] = tt * s->Fxyz[1];
+ s->Fsxyz[2] = tt * s->Fxyz[2];
+
+ /* Rescale so that the sum of the flare and the input doesn't exceed white */
+ s->Fsc = s->Wxyz[1]/(s->Fsxyz[1] + s->Wxyz[1]);
+ s->Fsxyz[0] *= s->Fsc;
+ s->Fsxyz[1] *= s->Fsc;
+ s->Fsxyz[2] *= s->Fsc;
+ s->Fisc = 1.0/s->Fsc;
+
+ /* Sharpened cone response white values */
+ s->rgbW[0] = 0.8562 * s->Wxyz[0] + 0.3372 * s->Wxyz[1] - 0.1934 * s->Wxyz[2];
+ s->rgbW[1] = -0.8360 * s->Wxyz[0] + 1.8327 * s->Wxyz[1] + 0.0033 * s->Wxyz[2];
+ s->rgbW[2] = 0.0357 * s->Wxyz[0] - 0.0469 * s->Wxyz[1] + 1.0112 * s->Wxyz[2];
+
+ /* Degree of chromatic adaptation */
+ s->D = s->F - (s->F / (1.0 + 2.0 * pow(s->La, 0.25) + s->La * s->La / 300.0) );
+
+ /* Chromaticaly transformed white value */
+ s->rgbcW[0] = (s->D * (1.0/s->rgbW[0]) + 1.0 - s->D ) * s->rgbW[0];
+ s->rgbcW[1] = (s->D * (1.0/s->rgbW[1]) + 1.0 - s->D ) * s->rgbW[1];
+ s->rgbcW[2] = (s->D * (1.0/s->rgbW[2]) + 1.0 - s->D ) * s->rgbW[2];
+
+ /* Transform from spectrally sharpened, to Hunt-Pointer_Estevez cone space */
+ s->rgbpW[0] = 0.6962394300923847 * s->rgbcW[0]
+ + 0.2492311682812913 * s->rgbcW[1]
+ + 0.0545394016263241 * s->rgbcW[2];
+ s->rgbpW[1] = 0.3054822636273227 * s->rgbcW[0]
+ + 0.5921282520433844 * s->rgbcW[1]
+ + 0.1023894843292929 * s->rgbcW[2];
+ s->rgbpW[2] = -0.0139683251072516 * s->rgbcW[0]
+ + 0.0278065725014340 * s->rgbcW[1]
+ + 0.9861617526058175 * s->rgbcW[2];
+
+ /* Background induction factor */
+ s->n = s->Yb/ s->Wxyz[1];
+ s->nn = pow((1.64 - pow(0.29, s->n)), 1.41); /* Pre computed value */
+
+ /* Lightness contrast factor ?? */
+ {
+ double k;
+
+ k = 1.0 / (5.0 * s->La + 1.0);
+ s->Fl = 0.2 * pow(k , 4.0) * 5.0 * s->La
+ + 0.1 * pow(1.0 - pow(k , 4.0) , 2.0) * pow(5.0 * s->La , 1.0/3.0);
+ }
+
+ /* Background and Chromatic brightness induction factors */
+ s->Nbb = 0.725 * pow(1.0/s->n, 0.2);
+ s->Ncb = s->Nbb;
+
+ /* Base exponential nonlinearity */
+ s->z = 1.0 + pow(s->n , 0.5);
+
+ /* Post-adapted cone response of white */
+ tt = pow(s->Fl * s->rgbpW[0], 0.73);
+ s->rgbaW[0] = (40.0 * tt / (tt + 2.0)) + 1.0;
+ tt = pow(s->Fl * s->rgbpW[1], 0.73);
+ s->rgbaW[1] = (40.0 * tt / (tt + 2.0)) + 1.0;
+ tt = pow(s->Fl * s->rgbpW[2], 0.73);
+ s->rgbaW[2] = (40.0 * tt / (tt + 2.0)) + 1.0;
+
+ /* Achromatic response of white */
+ s->Aw = (2.0 * s->rgbaW[0] + s->rgbaW[1] + (1.0/20.0) * s->rgbaW[2] - 3.05) * s->Nbb;
+
+#ifdef DIAG
+ printf("Scene parameters:\n");
+ printf("Viewing condition Ev = %d\n",s->Ev);
+ printf("Ref white Wxyz = %f %f %f\n", s->Wxyz[0], s->Wxyz[1], s->Wxyz[2]);
+ printf("Relative liminance of background Yb = %f\n", s->Yb);
+ printf("Adapting liminance La = %f\n", s->La);
+ printf("Flare Yf = %f\n", s->Yf);
+ printf("Flare color Fxyz = %f %f %f\n", s->Fxyz[0], s->Fxyz[1], s->Fxyz[2]);
+
+ printf("Internal parameters:\n");
+ printf("Surround Impact C = %f\n", s->C);
+ printf("Chromatic Induction Nc = %f\n", s->Nc);
+ printf("Adaptation Degree F = %f\n", s->F);
+
+ printf("Pre-computed values\n");
+ printf("Sharpened cone white rgbW = %f %f %f\n", s->rgbW[0], s->rgbW[1], s->rgbW[2]);
+ printf("Degree of chromatic adaptation D = %f\n", s->D);
+ printf("Chromatically transformed white rgbcW = %f %f %f\n", s->rgbcW[0], s->rgbcW[1], s->rgbcW[2]);
+ printf("Hunter-P-E cone response white rgbpW = %f %f %f\n", s->rgbpW[0], s->rgbpW[1], s->rgbpW[2]);
+ printf("Background induction factor n = %f\n", s->n);
+ printf("Lightness contrast factor Fl = %f\n", s->Fl);
+ printf("Background brightness induction factor Nbb = %f\n", s->Nbb);
+ printf("Chromatic brightness induction factor Ncb = %f\n", s->Ncb);
+ printf("Base exponential nonlinearity z = %f\n", s->z);
+ printf("Post adapted cone response white rgbaW = %f %f %f\n", s->rgbaW[0], s->rgbaW[1], s->rgbaW[2]);
+ printf("Achromatic response of white Aw = %f\n", s->Aw);
+#endif
+ return 0;
+}
+
+/* Conversions */
+static int XYZ_to_cam(
+struct _cam97s3 *s,
+double Jab[3],
+double XYZ[3]
+) {
+ int i;
+ double xyz[3], rgb[3], rgbp[3], rgba[3], rgbc[3];
+ double a, b, nab, J, C, h, e, A, ss;
+ double ttd, tt;
+
+ /* Add in flare */
+ xyz[0] = s->Fsc * XYZ[0] + s->Fsxyz[0];
+ xyz[1] = s->Fsc * XYZ[1] + s->Fsxyz[1];
+ xyz[2] = s->Fsc * XYZ[2] + s->Fsxyz[2];
+
+ /* Spectrally sharpened cone responses */
+ rgb[0] = 0.8562 * xyz[0] + 0.3372 * xyz[1] - 0.1934 * xyz[2];
+ rgb[1] = -0.8360 * xyz[0] + 1.8327 * xyz[1] + 0.0033 * xyz[2];
+ rgb[2] = 0.0357 * xyz[0] - 0.0469 * xyz[1] + 1.0112 * xyz[2];
+
+ /* Chromaticaly transformed sample value */
+ rgbc[0] = (s->D * (1.0/s->rgbW[0]) + 1.0 - s->D ) * rgb[0];
+ rgbc[1] = (s->D * (1.0/s->rgbW[1]) + 1.0 - s->D ) * rgb[1];
+ rgbc[2] = (s->D * (1.0/s->rgbW[2]) + 1.0 - s->D ) * rgb[2];
+
+ /* Transform from spectrally sharpened, to Hunt-Pointer_Estevez cone space */
+ rgbp[0] = 0.6962394300923847 * rgbc[0]
+ + 0.2492311682812913 * rgbc[1]
+ + 0.0545394016263241 * rgbc[2];
+ rgbp[1] = 0.3054822636273227 * rgbc[0]
+ + 0.5921282520433844 * rgbc[1]
+ + 0.1023894843292929 * rgbc[2];
+ rgbp[2] = -0.0139683251072516 * rgbc[0]
+ + 0.0278065725014340 * rgbc[1]
+ + 0.9861617526058175 * rgbc[2];
+
+ /* Post-adapted cone response of sample. */
+ /* rgba[] has a minimum value of 1.0 for XYZ[] = 0 and no flare. */
+ /* We add linear segments at the ends of this conversion to */
+ /* allow numerical handling of a wider range of values */
+ for (i = 0; i < 3; i++) {
+ if (rgbp[i] < 0.0) {
+ tt = pow(s->Fl * -rgbp[i], 0.73);
+ if (tt < 78.0)
+ rgba[i] = (2.0 - 39.0 * tt) / (tt + 2.0);
+ else
+ rgba[i] = (2.0 - tt) / 2.0;
+
+ } else {
+ tt = pow(s->Fl * rgbp[i], 0.73);
+ if (tt < 78.0)
+ rgba[i] = (41.0 * tt + 2.0) / (tt + 2.0);
+ else
+ rgba[i] = (tt + 2.0) / 2.0;
+ }
+ }
+
+ /* Preliminary red-green & yellow-blue opponent dimensions */
+ a = rgba[0] - 12.0 * rgba[1]/11.0 + rgba[2]/11.0;
+ b = (1.0/9.0) * (rgba[0] + rgba[1] - 2.0 * rgba[2]);
+ nab = sqrt(a * a + b * b); /* Normalised a, b */
+
+ /* Hue angle */
+ h = (180.0/CAM_PI) * atan2(b,a);
+ h = (h < 0.0) ? h + 360.0 : h;
+
+ /* Eccentricity factor */
+ {
+ double r, e1, e2, h1, h2;
+
+ if (h <= 20.14)
+ e1 = 0.8565, e2 = 0.8, h1 = 0.0, h2 = 20.14;
+ else if (h <= 90.0)
+ e1 = 0.8, e2 = 0.7, h1 = 20.14, h2 = 90.0;
+ else if (h <= 164.25)
+ e1 = 0.7, e2 = 1.0, h1 = 90.0, h2 = 164.25;
+ else if (h <= 237.53)
+ e1 = 1.0, e2 = 1.2, h1 = 164.25, h2 = 237.53;
+ else
+ e1 = 1.2, e2 = 0.8565, h1 = 237.53, h2 = 360.0;
+
+ r = (h-h1)/(h2-h1);
+#ifdef CIECAM97S3_SPLINE_E
+ r = r * r * (3.0 - 2.0 * r);
+#endif
+ e = e1 + r * (e2-e1);
+ }
+
+ /* Achromatic response */
+ /* Note that the minimum values of rgba[] for XYZ = 0 is 1.0, */
+ /* hence magic 3.05 below comes from the following weighting of rgba[], */
+ /* to base A at 0.0 */
+ A = (2.0 * rgba[0] + rgba[1] + (1.0/20.0) * rgba[2] - 3.05) * s->Nbb;
+
+ /* Lightness */
+ J = spow(A/s->Aw, s->C * s->z); /* J/100 - keep Sign */
+
+ /* Saturation */
+ /* Note that the minimum values for rgba[] for XYZ = 0 is 1.0 */
+ /* Hence magic 3.05 below comes from the following weighting of rgba[] */
+ ttd = rgba[0] + rgba[1] + (21.0/20.0) * rgba[2];
+ ttd = fabs(ttd);
+ if (ttd < 3.05) { /* If not physically realisable, limit denominator */
+ ttd = 3.05; /* hence limit max ss value */
+ }
+ ss = (50000.0/13.0 * s->Nc * s->Ncb * nab * e) / ttd;
+
+ /* Chroma - Keep C +ve and make sure J doesn't force it to 0 */
+ tt = fabs(J);
+ if (tt < 0.01)
+ tt = 0.01;
+ C = 0.7487 * pow(ss, 0.973) * pow(tt, 0.945 * s->n) * s->nn;
+
+ /* Helmholtz-Kohlraush effect */
+ if (s->hk) {
+ double kk = C/300.0 * sin(CAM_PI * fabs(0.5 * (h - 90.0))/180.0);
+ if (kk > 0.9) /* Limit kk to a reasonable range */
+ kk = 0.9;
+ J = J + (1.0 - J) * kk;
+ }
+
+ J *= 100.0; /* Scale J */
+
+ /* Compute Jab value */
+ Jab[0] = J;
+ if (nab > 1e-10) {
+ Jab[1] = C * a/nab;
+ Jab[2] = C * b/nab;
+ } else {
+ Jab[1] = 0.0;
+ Jab[2] = 0.0;
+ }
+
+#ifdef DIAG
+ printf("Processing:\n");
+ printf("XYZ = %f %f %f\n", XYZ[0], XYZ[1], XYZ[2]);
+ printf("Including flare XYZ = %f %f %f\n", xyz[0], xyz[1], xyz[2]);
+ printf("Sharpened cone sample rgb = %f %f %f\n", rgb[0], rgb[1], rgb[2]);
+ printf("Chromatically transformed sample value rgbc = %f %f %f\n", rgbc[0], rgbc[1], rgbc[2]);
+ printf("Hunt-P-E cone space rgbp = %f %f %f\n", rgbp[0], rgbp[1], rgbp[2]);
+ printf("Post adapted cone response rgba = %f %f %f\n", rgba[0], rgba[1], rgba[2]);
+ printf("Prelim red green a = %f, b = %f\n", a, b);
+ printf("Hue angle h = %f\n", h);
+ printf("Eccentricity factor e = %f\n", e);
+ printf("Achromatic response A = %f\n", A);
+ printf("Lightness J = %f\n", J);
+ printf("Saturation ss = %f\n", ss);
+ printf("Chroma C = %f\n", C);
+ printf("Jab = %f %f %f\n", Jab[0], Jab[1], Jab[2]);
+#endif
+ return 0;
+}
+
+static int cam_to_XYZ(
+struct _cam97s3 *s,
+double XYZ[3],
+double Jab[3]
+) {
+ int i;
+ double xyz[3], rgb[3], rgbp[3], rgba[3], rgbc[3];
+ double ja, jb, aa, ab, a, b, J, C, h, e, A, ss;
+ double tt, ttA, tte;
+
+ J = Jab[0] * 0.01; /* J/100 */
+ ja = Jab[1];
+ jb = Jab[2];
+
+ /* Compute hue angle */
+ h = (180.0/CAM_PI) * atan2(jb, ja);
+ h = (h < 0.0) ? h + 360.0 : h;
+
+ /* Compute chroma value */
+ C = sqrt(ja * ja + jb * jb); /* Must be Always +ve */
+
+ /* Helmholtz-Kohlraush effect */
+ if (s->hk) {
+ double kk = C/300.0 * sin(CAM_PI * fabs(0.5 * (h - 90.0))/180.0);
+ if (kk > 0.9) /* Limit kk to a reasonable range */
+ kk = 0.9;
+ J = (J - kk)/(1.0 - kk);
+ }
+
+ /* Eccentricity factor */
+ {
+ double r, e1, e2, h1, h2;
+
+ if (h <= 20.14)
+ e1 = 0.8565, e2 = 0.8, h1 = 0.0, h2 = 20.14;
+ else if (h <= 90.0)
+ e1 = 0.8, e2 = 0.7, h1 = 20.14, h2 = 90.0;
+ else if (h <= 164.25)
+ e1 = 0.7, e2 = 1.0, h1 = 90.0, h2 = 164.25;
+ else if (h <= 237.53)
+ e1 = 1.0, e2 = 1.2, h1 = 164.25, h2 = 237.53;
+ else
+ e1 = 1.2, e2 = 0.8565, h1 = 237.53, h2 = 360.0;
+
+ r = (h-h1)/(h2-h1);
+#ifdef CIECAM97S3_SPLINE_E
+ r = r * r * (3.0 - 2.0 * r);
+#endif
+ e = e1 + r * (e2-e1);
+ }
+
+ /* Achromatic response */
+ A = spow(J, 1.0/(s->C * s->z)) * s->Aw; /* Keep sign of J */
+
+ /* Saturation - keep +ve and make sure J = 0 doesn't blow it up. */
+ tt = fabs(J);
+ if (tt < 0.01)
+ tt = 0.01;
+ ss = pow(C/(0.7487 * pow(tt, 0.945 * s->n) * s->nn), 1.0/0.973); /* keep +ve */
+
+ /* Compute a & b, taking care of numerical problems */
+ aa = fabs(ja);
+ ab = fabs(jb);
+ ttA = (A/s->Nbb)+3.05; /* Common factor */
+ tte = 50000.0/13.0 * e * s->Nc * s->Ncb; /* Common factor */
+
+ if (aa < 1e-10 && ab < 1e-10) {
+ a = ja;
+ b = jb;
+ } else if (aa > ab) {
+ double tanh = jb/ja;
+ double sign = (h > 90.0 && h <= 270.0) ? -1.0 : 1.0;
+
+ if (ttA < 0.0)
+ sign = -sign;
+
+ a = (ss * ttA)
+ / (sign * sqrt(1.0 + tanh * tanh) * tte + (ss * (11.0/23.0 + (108.0/23.0) * tanh)));
+ b = a * tanh;
+
+ } else { /* ab > aa */
+ double itanh = ja/jb;
+ double sign = (h > 180.0 && h <= 360.0) ? -1.0 : 1.0;
+
+ if (ttA < 0.0)
+ sign = -sign;
+
+ b = (ss * ttA)
+ / (sign * sqrt(1.0 + itanh * itanh) * tte + (ss * (108.0/23.0 + (11.0/23.0) * itanh)));
+ a = b * itanh;
+ }
+
+ { /* Check if we have a limited saturation because it is non-realisable */
+ double tts;
+ double nab = sqrt(a * a + b * b); /* Normalised a, b */
+ tts = (nab * tte) / 3.05; /* Limited saturation number */
+ if (tts < ss) { /* Saturation exceeds it anyway so must have limited denom. */
+ a *= ss/tts; /* Rescale a & b to account for extra ss */
+ b *= ss/tts; /* even though denom was limited (since nab was in numerator). */
+ }
+ }
+
+ /* Post-adapted cone response of sample */
+ rgba[0] = (20.0/61.0) * ttA
+ + ((41.0 * 11.0)/(61.0 * 23.0)) * a
+ + ((288.0 * 1.0)/(61.0 * 23.0)) * b;
+ rgba[1] = (20.0/61.0) * ttA
+ - ((81.0 * 11.0)/(61.0 * 23.0)) * a
+ - ((261.0 * 1.0)/(61.0 * 23.0)) * b;
+ rgba[2] = (20.0/61.0) * ttA
+ - ((20.0 * 11.0)/(61.0 * 23.0)) * a
+ - ((20.0 * 315.0)/(61.0 * 23.0)) * b;
+
+ /* Hunt-Pointer_Estevez cone space */
+ /* (with linear segments at the ends0 */
+ tt = 1.0/s->Fl;
+ for (i = 0; i < 3; i++) {
+ if (rgba[i] < 1.0) {
+ double ta = rgba[i] > -38.0 ? rgba[i] : -38.0;
+ rgbp[i] = -tt * pow((2.0 - 2.0 * rgba[i] )/(39.0+ ta), 1.0/0.73);
+ } else {
+ double ta = rgba[i] < 40.0 ? rgba[i] : 40.0;
+ rgbp[i] = tt * pow((2.0 * rgba[i] -2.0)/(41.0 - ta), 1.0/0.73);
+ }
+ }
+
+ /* Chromaticaly transformed sample value */
+ rgbc[0] = 1.7605948990728097 * rgbp[0]
+ - 0.7400833814121892 * rgbp[1]
+ - 0.0205291236096116 * rgbp[2];
+ rgbc[1] = -0.9170843265341294 * rgbp[0]
+ + 2.0826033118941054 * rgbp[1]
+ - 0.1655098145167107 * rgbp[2];
+ rgbc[2] = 0.0507964678367941 * rgbp[0]
+ - 0.0692054676442407 * rgbp[1]
+ + 1.0184084918427683 * rgbp[2];
+
+ /* Spectrally sharpened cone responses */
+ rgb[0] = rgbc[0]/(s->D * (1.0/s->rgbW[0]) + 1.0 - s->D);
+ rgb[1] = rgbc[1]/(s->D * (1.0/s->rgbW[1]) + 1.0 - s->D);
+ rgb[2] = rgbc[2]/(s->D * (1.0/s->rgbW[2]) + 1.0 - s->D);
+
+ /* XYZ values */
+ xyz[0] = 0.9873999149199270 * rgb[0]
+ - 0.1768250198556842 * rgb[1]
+ + 0.1894251049357572 * rgb[2];
+ xyz[1] = 0.4504351090445316 * rgb[0]
+ + 0.4649328977527109 * rgb[1]
+ + 0.0846319932027575 * rgb[2];
+ xyz[2] = -0.0139683251072516 * rgb[0]
+ + 0.0278065725014340 * rgb[1]
+ + 0.9861617526058175 * rgb[2];
+
+ /* Subtract flare */
+ XYZ[0] = s->Fisc * (xyz[0] - s->Fsxyz[0]);
+ XYZ[1] = s->Fisc * (xyz[1] - s->Fsxyz[1]);
+ XYZ[2] = s->Fisc * (xyz[2] - s->Fsxyz[2]);
+
+#ifdef DIAG
+ printf("Processing:\n");
+ printf("Jab = %f %f %f\n", Jab[0], Jab[1], Jab[2]);
+ printf("Chroma C = %f\n", C);
+ printf("Saturation ss = %f\n", ss);
+ printf("Lightness J = %f\n", J * 100.0);
+ printf("Achromatic response A = %f\n", A);
+ printf("Eccentricity factor e = %f\n", e);
+ printf("Hue angle h = %f\n", h);
+ printf("Prelim red green a = %f, b = %f\n", a, b);
+ printf("Post adapted cone response rgba = %f %f %f\n", rgba[0], rgba[1], rgba[2]);
+ printf("Hunt-P-E cone space rgbp = %f %f %f\n", rgbp[0], rgbp[1], rgbp[2]);
+ printf("Chromatically transformed sample value rgbc = %f %f %f\n", rgbc[0], rgbc[1], rgbc[2]);
+ printf("Sharpened cone sample rgb = %f %f %f\n", rgb[0], rgb[1], rgb[2]);
+ printf("Including flare XYZ = %f %f %f\n", xyz[0], xyz[1], xyz[2]);
+ printf("XYZ = %f %f %f\n", XYZ[0], XYZ[1], XYZ[2]);
+#endif
+ return 0;
+}
+
+
+
+