/*---------------------------------------------------------------------
* xyzmap_oFunc -- output-table functions (inverse of input mappings)
*---------------------------------------------------------------------
*/
double
xyzmap_oFunc (double q, fut_calcData_p dataP)
{
double s;
s = q;
/* Recover headroom: */
s = 1.4 * s; /* [0, 1] -> [0, 1.4] */
/* Linearize */
s = Hinverse (s, &(((auxData_p)dataP)->lc)); /* [0, 1.4] -> [0, 2.4] -> [0, 1.205] */
/* Interpret according to white point and rescale for ICC: */
switch (dataP->chan) {
case 0:
s *= (KCP_D50_X * XYZSCALE); /* X */
break;
case 1:
s *= (KCP_D50_Y * XYZSCALE); /* Y */
break;
case 2:
s *= (KCP_D50_Z * XYZSCALE); /* Z */
break;
}
s = RESTRICT (s, 0.0, 1.0);
return s;
}
/*---------------------------------------------------------------------
* cmyklini_iFunc -- input mappings
*---------------------------------------------------------------------
*/
double
cmyklin_iFunc ( double a,
fut_calcData_p dataP)
{
a = (a + L0) / (1.0 + L0);
a = Hinverse (a, &(((auxData_p)dataP)->lc));
a = (a - YMIN) / (1.0 - YMIN);
return RESTRICT (a, 0.0, 1.0);
}
/*---------------------------------------------------------------------
* uvLLab_gFun -- grid-table functions
*---------------------------------------------------------------------
*/
double uvLLab_gFun (double_p dP, fut_calcData_p dataP)
{
double u = dP[0], v = dP[1], l = dP[2];
double x, y, z, p, delta, a, astar, bstar;
/* Decode piecewise linear functions of u and v: */
delta = u - UGRID0;
a = (delta > 0.0) ? ((auxData_p)dataP)->uvLLabC.bu1 : ((auxData_p)dataP)->uvLLabC.bu0;
delta = UNMAP (delta, a);
u = U0 + delta;
delta = v - VGRID0;
a = (delta > 0.0) ? ((auxData_p)dataP)->uvLLabC.bv1 : ((auxData_p)dataP)->uvLLabC.bv0;
delta = UNMAP (delta, a);
v = V0 + delta;
u = 0.070 + 0.40996784565916 * u; /* CIE 1976 u' */
v = 0.165 + 0.41986827661910 * v; /* CIE 1976 v' */
/* Compute CIE 1931 tristimulus values: */
y = Hinverse (l, &(((auxData_p)dataP)->lc)); /* CIE 1931 Y */
y = (254.0 * y + 1.0) / 255.0; /* recompress for Prophecy */
x = 2.25 * (u / v) * y; /* CIE 1931 X */
z = ((3.0 - 0.75 * u) / v - 5.0) * y; /* CIE 1931 Z */
/* Scale to white point: */
x /= XWHITE;
y /= YWHITE;
z /= ZWHITE;
/* Convert to CIELAB: */
astar = (Hfunc (x, &(((auxData_p)dataP)->lc)) - Hfunc (y, &(((auxData_p)dataP)->lc))) / 0.00232; /* CIE 1976 a* */
bstar = (Hfunc (y, &(((auxData_p)dataP)->lc)) - Hfunc (z, &(((auxData_p)dataP)->lc))) / 0.00580; /* CIE 1976 b* */
/* Encode CIELAB for L* in [0, 100] and a* & b* in [-200, 200]: */
switch (dataP->chan) {
case 0: /* (L*)/100 */
p = Hfunc (y, &(((auxData_p)dataP)->lc));
break;
case 1: /* ~ 1/2 + (a*)/400 */
p = MID12BIT + 0.0025 * astar;
break;
case 2: /* ~ 1/2 + (b*)/400 */
p = MID12BIT + 0.0025 * bstar;
break;
default:
p = 6.023e+23; /* Avogadro's number */
break;
}
return RESTRICT (p, 0.0, 1.0);
}
double uvLLab_iL (double l, fut_calcData_p dataP) /* piecewise linear in v' */
{
double y;
#if defined KCP_MAP_BASE_MAX_REF
l *= KCP_16_TO_8_ENCODING;
#endif
/* Convert to luminance: */
y = Hinverse (l, &(((auxData_p)dataP)->lc)); /* ==> y is compressed relative luminance */
y = (255.0 * y - 1.0) / 254.0; /* decompress for L*a*b* */
/* Convert back to (L*)/100: */
l = Hfunc (y, &(((auxData_p)dataP)->lc)); /* (L*)/100, in [-0.0356, 1] */
return RESTRICT (l, 0.0, 1.0);
}
/*----------------------------------------------------------------------------
* outfun -- rescale and clip a* and b*; decompress L*
*----------------------------------------------------------------------------
*/
double uvLLab_oFun (double p, fut_calcData_p dataP)
{
switch (dataP->chan) {
case 0:
p = Hinverse (p, &(((auxData_p)dataP)->lc)); /* Y */
p = (255.0 * p - 1.0) / 254.0; /* decompress from Prophecy Dmax */
p = Hfunc (p, &(((auxData_p)dataP)->lc)); /* (L*)/100, in [-0.0356, 1] */
break;
case 1:
case 2: p = 400.0 * (p - MID12BIT); /* CIE 1976 a*, b*, in [-200, 200] */
p = RESTRICT (p, -128.0, 127.0); /* clip to [-128, 127] */
p = p + 128.0; /* -> [0, 255] */
p /= 255.0; /* from [0, 255] to [0, 1] */
break;
default:
p = 6.023e+23;
break;
}
#if defined KCP_MAP_BASE_MAX_REF
p *= KCP_8_TO_16_ENCODING;
#endif
return RESTRICT (p, 0.0, 1.0); /* L* in [0, 100]; a* & b* in [-128, 127] */
}
