6 |
|
*/ |
7 |
|
|
8 |
|
#include <stdio.h> |
9 |
+ |
#include <stdlib.h> |
10 |
|
#include <math.h> |
11 |
|
#include "ccolor.h" |
12 |
|
|
13 |
+ |
#undef frand |
14 |
+ |
#define frand() (rand()*(1./(RAND_MAX+.5))) |
15 |
|
|
16 |
< |
C_COLOR c_dfcolor = C_DEFCOLOR; |
16 |
> |
/* Sharp primary matrix */ |
17 |
> |
float XYZtoSharp[3][3] = { |
18 |
> |
{ 1.2694, -0.0988, -0.1706}, |
19 |
> |
{-0.8364, 1.8006, 0.0357}, |
20 |
> |
{ 0.0297, -0.0315, 1.0018} |
21 |
> |
}; |
22 |
> |
/* inverse Sharp primary matrix */ |
23 |
> |
float XYZfromSharp[3][3] = { |
24 |
> |
{ 0.8156, 0.0472, 0.1372}, |
25 |
> |
{ 0.3791, 0.5769, 0.0440}, |
26 |
> |
{-0.0123, 0.0167, 0.9955} |
27 |
> |
}; |
28 |
|
|
29 |
+ |
const C_COLOR c_dfcolor = C_DEFCOLOR; |
30 |
+ |
|
31 |
+ |
const C_CHROMA c_dfchroma = 49750; /* c_encodeChroma(&c_dfcolor) */ |
32 |
+ |
|
33 |
|
/* CIE 1931 Standard Observer curves */ |
34 |
< |
static const C_COLOR cie_xf = { 1, NULL, C_CDSPEC|C_CSSPEC|C_CSXY|C_CSEFF, |
34 |
> |
const C_COLOR c_x31 = { 1, NULL, C_CDSPEC|C_CSSPEC|C_CSXY|C_CSEFF, |
35 |
|
{14,42,143,435,1344,2839,3483,3362,2908,1954,956, |
36 |
|
320,49,93,633,1655,2904,4334,5945,7621,9163,10263, |
37 |
|
10622,10026,8544,6424,4479,2835,1649,874,468,227, |
38 |
|
114,58,29,14,7,3,2,1,0}, 106836L, .467, .368, 362.230 |
39 |
|
}; |
40 |
< |
static const C_COLOR cie_yf = { 1, NULL, C_CDSPEC|C_CSSPEC|C_CSXY|C_CSEFF, |
40 |
> |
const C_COLOR c_y31 = { 1, NULL, C_CDSPEC|C_CSSPEC|C_CSXY|C_CSEFF, |
41 |
|
{0,1,4,12,40,116,230,380,600,910,1390,2080,3230, |
42 |
|
5030,7100,8620,9540,9950,9950,9520,8700,7570,6310, |
43 |
|
5030,3810,2650,1750,1070,610,320,170,82,41,21,10, |
44 |
|
5,2,1,1,0,0}, 106856L, .398, .542, 493.525 |
45 |
|
}; |
46 |
< |
static const C_COLOR cie_zf = { 1, NULL, C_CDSPEC|C_CSSPEC|C_CSXY|C_CSEFF, |
46 |
> |
const C_COLOR c_z31 = { 1, NULL, C_CDSPEC|C_CSSPEC|C_CSXY|C_CSEFF, |
47 |
|
{65,201,679,2074,6456,13856,17471,17721,16692, |
48 |
|
12876,8130,4652,2720,1582,782,422,203,87,39,21,17, |
49 |
|
11,8,3,2,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}, |
75 |
|
36057L, .0, .0, |
76 |
|
}; |
77 |
|
|
60 |
– |
/* Sharp primary matrix */ |
61 |
– |
static const float toSharp[3][3] = { |
62 |
– |
{ 1.2694, -0.0988, -0.1706}, |
63 |
– |
{-0.8364, 1.8006, 0.0357}, |
64 |
– |
{ 0.0297, -0.0315, 1.0018} |
65 |
– |
}; |
66 |
– |
/* inverse Sharp primary matrix */ |
67 |
– |
static const float fromSharp[3][3] = { |
68 |
– |
{ 0.8156, 0.0472, 0.1372}, |
69 |
– |
{ 0.3791, 0.5769, 0.0440}, |
70 |
– |
{-0.0123, 0.0167, 0.9955} |
71 |
– |
}; |
78 |
|
|
79 |
< |
static void |
79 |
> |
/* convert to sharpened RGB color for low-error operations */ |
80 |
> |
void |
81 |
|
c_toSharpRGB(C_COLOR *cin, double cieY, float cout[3]) |
82 |
|
{ |
83 |
|
double xyz[3]; |
88 |
|
xyz[1] = cieY; |
89 |
|
xyz[2] = (1. - cin->cx - cin->cy)/cin->cy * cieY; |
90 |
|
|
91 |
< |
cout[0] = toSharp[0][0]*xyz[0] + toSharp[0][1]*xyz[1] + |
92 |
< |
toSharp[0][2]*xyz[2]; |
93 |
< |
cout[1] = toSharp[1][0]*xyz[0] + toSharp[1][1]*xyz[1] + |
94 |
< |
toSharp[1][2]*xyz[2]; |
95 |
< |
cout[2] = toSharp[2][0]*xyz[0] + toSharp[2][1]*xyz[1] + |
96 |
< |
toSharp[2][2]*xyz[2]; |
91 |
> |
cout[0] = XYZtoSharp[0][0]*xyz[0] + XYZtoSharp[0][1]*xyz[1] + |
92 |
> |
XYZtoSharp[0][2]*xyz[2]; |
93 |
> |
cout[1] = XYZtoSharp[1][0]*xyz[0] + XYZtoSharp[1][1]*xyz[1] + |
94 |
> |
XYZtoSharp[1][2]*xyz[2]; |
95 |
> |
cout[2] = XYZtoSharp[2][0]*xyz[0] + XYZtoSharp[2][1]*xyz[1] + |
96 |
> |
XYZtoSharp[2][2]*xyz[2]; |
97 |
|
} |
98 |
|
|
99 |
< |
static double |
99 |
> |
/* convert back from sharpened RGB color */ |
100 |
> |
double |
101 |
|
c_fromSharpRGB(float cin[3], C_COLOR *cout) |
102 |
|
{ |
103 |
|
double xyz[3], sf; |
104 |
|
|
105 |
< |
xyz[0] = fromSharp[0][0]*cin[0] + fromSharp[0][1]*cin[1] + |
106 |
< |
fromSharp[0][2]*cin[2]; |
107 |
< |
xyz[1] = fromSharp[1][0]*cin[0] + fromSharp[1][1]*cin[1] + |
108 |
< |
fromSharp[1][2]*cin[2]; |
109 |
< |
xyz[2] = fromSharp[2][0]*cin[0] + fromSharp[2][1]*cin[1] + |
110 |
< |
fromSharp[2][2]*cin[2]; |
111 |
< |
|
105 |
> |
xyz[1] = XYZfromSharp[1][0]*cin[0] + XYZfromSharp[1][1]*cin[1] + |
106 |
> |
XYZfromSharp[1][2]*cin[2]; |
107 |
> |
if (xyz[1] <= 1e-6) { |
108 |
> |
*cout = c_dfcolor; /* punting, here... */ |
109 |
> |
return xyz[1]; |
110 |
> |
} |
111 |
> |
xyz[0] = XYZfromSharp[0][0]*cin[0] + XYZfromSharp[0][1]*cin[1] + |
112 |
> |
XYZfromSharp[0][2]*cin[2]; |
113 |
> |
xyz[2] = XYZfromSharp[2][0]*cin[0] + XYZfromSharp[2][1]*cin[1] + |
114 |
> |
XYZfromSharp[2][2]*cin[2]; |
115 |
> |
|
116 |
|
sf = 1./(xyz[0] + xyz[1] + xyz[2]); |
117 |
|
|
118 |
|
cout->cx = xyz[0] * sf; |
122 |
|
return(xyz[1]); |
123 |
|
} |
124 |
|
|
125 |
+ |
/* assign arbitrary spectrum and return Y value */ |
126 |
+ |
double |
127 |
+ |
c_sset(C_COLOR *clr, double wlmin, double wlmax, const float spec[], int nwl) |
128 |
+ |
{ |
129 |
+ |
double yval, scale; |
130 |
+ |
float va[C_CNSS]; |
131 |
+ |
int i, pos, n, imax, wl; |
132 |
+ |
double wl0, wlstep; |
133 |
+ |
double boxpos, boxstep; |
134 |
+ |
/* check arguments */ |
135 |
+ |
if ((nwl <= 1) | (spec == NULL) | (wlmin >= C_CMAXWL) | |
136 |
+ |
(wlmax <= C_CMINWL) | (wlmin >= wlmax)) |
137 |
+ |
return(0.); |
138 |
+ |
wlstep = (wlmax - wlmin)/(nwl-1); |
139 |
+ |
while (wlmin < C_CMINWL) { |
140 |
+ |
wlmin += wlstep; |
141 |
+ |
--nwl; ++spec; |
142 |
+ |
} |
143 |
+ |
while (wlmax > C_CMAXWL) { |
144 |
+ |
wlmax -= wlstep; |
145 |
+ |
--nwl; |
146 |
+ |
} |
147 |
+ |
if ((nwl <= 1) | (wlmin >= wlmax)) |
148 |
+ |
return(0.); |
149 |
+ |
imax = nwl; /* box filter if necessary */ |
150 |
+ |
boxpos = 0; |
151 |
+ |
boxstep = 1; |
152 |
+ |
if (wlstep < C_CWLI) { |
153 |
+ |
imax = (wlmax - wlmin)/C_CWLI + 1e-7; |
154 |
+ |
boxpos = (wlmin - C_CMINWL)/C_CWLI; |
155 |
+ |
boxstep = wlstep/C_CWLI; |
156 |
+ |
wlstep = C_CWLI; |
157 |
+ |
} |
158 |
+ |
scale = 0.; /* get values and maximum */ |
159 |
+ |
yval = 0.; |
160 |
+ |
pos = 0; |
161 |
+ |
for (i = 0; i < imax; i++) { |
162 |
+ |
va[i] = 0.; n = 0; |
163 |
+ |
while (boxpos < i+.5 && pos < nwl) { |
164 |
+ |
va[i] += spec[pos++]; |
165 |
+ |
n++; |
166 |
+ |
boxpos += boxstep; |
167 |
+ |
} |
168 |
+ |
if (n > 1) |
169 |
+ |
va[i] /= (double)n; |
170 |
+ |
if (va[i] > scale) |
171 |
+ |
scale = va[i]; |
172 |
+ |
else if (va[i] < -scale) |
173 |
+ |
scale = -va[i]; |
174 |
+ |
yval += va[i] * c_y31.ssamp[i]; |
175 |
+ |
} |
176 |
+ |
if (scale <= 1e-7) |
177 |
+ |
return(0.); |
178 |
+ |
yval /= (double)c_y31.ssum; |
179 |
+ |
scale = C_CMAXV / scale; |
180 |
+ |
clr->ssum = 0; /* convert to our spacing */ |
181 |
+ |
wl0 = wlmin; |
182 |
+ |
pos = 0; |
183 |
+ |
for (i = 0, wl = C_CMINWL; i < C_CNSS; i++, wl += C_CWLI) |
184 |
+ |
if ((wl < wlmin) | (wl > wlmax)) |
185 |
+ |
clr->ssamp[i] = 0; |
186 |
+ |
else { |
187 |
+ |
while (wl0 + wlstep < wl+1e-7) { |
188 |
+ |
wl0 += wlstep; |
189 |
+ |
pos++; |
190 |
+ |
} |
191 |
+ |
if ((wl+1e-7 >= wl0) & (wl-1e-7 <= wl0)) |
192 |
+ |
clr->ssamp[i] = scale*va[pos] + frand(); |
193 |
+ |
else /* interpolate if necessary */ |
194 |
+ |
clr->ssamp[i] = frand() + scale / wlstep * |
195 |
+ |
( va[pos]*(wl0+wlstep - wl) + |
196 |
+ |
va[pos+1]*(wl - wl0) ); |
197 |
+ |
clr->ssum += clr->ssamp[i]; |
198 |
+ |
} |
199 |
+ |
clr->flags = C_CDSPEC|C_CSSPEC; |
200 |
+ |
return(yval); |
201 |
+ |
} |
202 |
+ |
|
203 |
|
/* check if color is grey */ |
204 |
|
int |
205 |
|
c_isgrey(C_COLOR *clr) |
230 |
|
if (fl & C_CSXY) { /* cspec -> cxy */ |
231 |
|
x = y = z = 0.; |
232 |
|
for (i = 0; i < C_CNSS; i++) { |
233 |
< |
x += cie_xf.ssamp[i] * clr->ssamp[i]; |
234 |
< |
y += cie_yf.ssamp[i] * clr->ssamp[i]; |
235 |
< |
z += cie_zf.ssamp[i] * clr->ssamp[i]; |
233 |
> |
x += c_x31.ssamp[i] * clr->ssamp[i]; |
234 |
> |
y += c_y31.ssamp[i] * clr->ssamp[i]; |
235 |
> |
z += c_z31.ssamp[i] * clr->ssamp[i]; |
236 |
|
} |
237 |
< |
x /= (double)cie_xf.ssum; |
238 |
< |
y /= (double)cie_yf.ssum; |
239 |
< |
z /= (double)cie_zf.ssum; |
237 |
> |
x /= (double)c_x31.ssum; |
238 |
> |
y /= (double)c_y31.ssum; |
239 |
> |
z /= (double)c_z31.ssum; |
240 |
|
z += x + y; |
241 |
|
clr->cx = x / z; |
242 |
|
clr->cy = y / z; |
243 |
|
clr->flags |= C_CSXY; |
244 |
< |
} else if (fl & C_CSSPEC) { /* cxy -> cspec */ |
244 |
> |
} |
245 |
> |
if (fl & C_CSSPEC) { /* cxy -> cspec */ |
246 |
|
x = clr->cx; |
247 |
|
y = clr->cy; |
248 |
|
z = 1. - x - y; |
249 |
|
clr->ssum = 0; |
250 |
|
for (i = 0; i < C_CNSS; i++) { |
251 |
|
clr->ssamp[i] = x*cie_xp.ssamp[i] + y*cie_yp.ssamp[i] |
252 |
< |
+ z*cie_zp.ssamp[i] + .5; |
252 |
> |
+ z*cie_zp.ssamp[i] + frand(); |
253 |
|
if (clr->ssamp[i] < 0) /* out of gamut! */ |
254 |
|
clr->ssamp[i] = 0; |
255 |
|
else |
261 |
|
if (clr->flags & C_CSSPEC) { /* from spectrum */ |
262 |
|
y = 0.; |
263 |
|
for (i = 0; i < C_CNSS; i++) |
264 |
< |
y += cie_yf.ssamp[i] * clr->ssamp[i]; |
264 |
> |
y += c_y31.ssamp[i] * clr->ssamp[i]; |
265 |
|
clr->eff = C_CLPWM * y / clr->ssum; |
266 |
|
} else /* clr->flags & C_CSXY */ { /* from (x,y) */ |
267 |
< |
clr->eff = clr->cx*cie_xf.eff + clr->cy*cie_yf.eff + |
268 |
< |
(1. - clr->cx - clr->cy)*cie_zf.eff; |
267 |
> |
clr->eff = clr->cx*c_x31.eff + clr->cy*c_y31.eff + |
268 |
> |
(1. - clr->cx - clr->cy)*c_z31.eff; |
269 |
|
} |
270 |
|
clr->flags |= C_CSEFF; |
271 |
|
} |
290 |
|
cmix[i] = w1*c1->ssamp[i] + w2*c2->ssamp[i]; |
291 |
|
if (cmix[i] > scale) |
292 |
|
scale = cmix[i]; |
293 |
+ |
else if (cmix[i] < -scale) |
294 |
+ |
scale = -cmix[i]; |
295 |
|
} |
296 |
|
scale = C_CMAXV / scale; |
297 |
|
cres->ssum = 0; |
298 |
|
for (i = 0; i < C_CNSS; i++) |
299 |
< |
cres->ssum += cres->ssamp[i] = scale*cmix[i] + .5; |
299 |
> |
cres->ssum += cres->ssamp[i] = scale*cmix[i] + frand(); |
300 |
|
cres->flags = C_CDSPEC|C_CSSPEC; |
301 |
|
} else { /* CIE xy mixing */ |
302 |
|
c_ccvt(c1, C_CSXY); |
331 |
|
cmix[i] = c1->ssamp[i] * c2->ssamp[i]; |
332 |
|
if (cmix[i] > cmax) |
333 |
|
cmax = cmix[i]; |
334 |
+ |
else if (cmix[i] < -cmax) |
335 |
+ |
cmax = -cmix[i]; |
336 |
|
} |
337 |
|
cmax /= C_CMAXV; |
338 |
|
if (!cmax) { |
344 |
|
cres->ssum += cres->ssamp[i] = cmix[i] / cmax; |
345 |
|
cres->flags = C_CDSPEC|C_CSSPEC; |
346 |
|
|
347 |
< |
c_ccvt(cres, C_CSEFF); /* nasty, but true */ |
348 |
< |
yres = (y1 * y2 * cie_yf.ssum * C_CLPWM) / |
347 |
> |
c_ccvt(cres, C_CSEFF); /* below is correct */ |
348 |
> |
yres = y1 * y2 * c_y31.ssum * C_CLPWM / |
349 |
|
(c1->eff*c1->ssum * c2->eff*c2->ssum) * |
350 |
|
cres->eff*( cres->ssum*(double)cmax + |
351 |
|
C_CNSS/2.0*(cmax-1) ); |
386 |
|
clr->ssum = 0; |
387 |
|
for (i = 0; i < C_CNSS; i++) { |
388 |
|
wl = (C_CMINWL + i*C_CWLI)*1e-9; |
389 |
< |
clr->ssum += clr->ssamp[i] = sf*bbsp(wl,tk) + .5; |
389 |
> |
clr->ssum += clr->ssamp[i] = sf*bbsp(wl,tk) + frand(); |
390 |
|
} |
391 |
|
clr->flags = C_CDSPEC|C_CSSPEC; |
392 |
|
return(1); |
396 |
|
#undef C2 |
397 |
|
#undef bbsp |
398 |
|
#undef bblm |
399 |
+ |
|
400 |
+ |
#define UV_NORMF 410. |
401 |
+ |
|
402 |
+ |
/* encode (x,y) chromaticity */ |
403 |
+ |
C_CHROMA |
404 |
+ |
c_encodeChroma(C_COLOR *clr) |
405 |
+ |
{ |
406 |
+ |
double df; |
407 |
+ |
int ub, vb; |
408 |
+ |
|
409 |
+ |
c_ccvt(clr, C_CSXY); |
410 |
+ |
df = UV_NORMF/(-2.*clr->cx + 12.*clr->cy + 3.); |
411 |
+ |
ub = 4.*clr->cx*df + frand(); |
412 |
+ |
if (ub > 0xff) ub = 0xff; |
413 |
+ |
else ub *= (ub > 0); |
414 |
+ |
vb = 9.*clr->cy*df + frand(); |
415 |
+ |
if (vb > 0xff) vb = 0xff; |
416 |
+ |
else vb *= (vb > 0); |
417 |
+ |
|
418 |
+ |
return(vb<<8 | ub); |
419 |
+ |
} |
420 |
+ |
|
421 |
+ |
/* decode (x,y) chromaticity */ |
422 |
+ |
void |
423 |
+ |
c_decodeChroma(C_COLOR *cres, C_CHROMA ccode) |
424 |
+ |
{ |
425 |
+ |
double up = (ccode & 0xff)*(1./UV_NORMF); |
426 |
+ |
double vp = (ccode>>8 & 0xff)*(1./UV_NORMF); |
427 |
+ |
double df = 1./(6.*up - 16.*vp + 12.); |
428 |
+ |
|
429 |
+ |
cres->cx = 9.*up * df; |
430 |
+ |
cres->cy = 4.*vp * df; |
431 |
+ |
cres->flags = C_CDXY|C_CSXY; |
432 |
+ |
} |
433 |
+ |
|
434 |
+ |
#undef UV_NORMF |