1 |
greg |
1.1 |
/* Copyright (c) 1986 Regents of the University of California */ |
2 |
|
|
|
3 |
|
|
#ifndef lint |
4 |
|
|
static char SCCSid[] = "$SunId$ LBL"; |
5 |
|
|
#endif |
6 |
|
|
|
7 |
|
|
/* |
8 |
|
|
* color.c - routines for color calculations. |
9 |
|
|
* |
10 |
|
|
* 10/10/85 |
11 |
|
|
*/ |
12 |
|
|
|
13 |
|
|
#include <stdio.h> |
14 |
|
|
|
15 |
|
|
#include "color.h" |
16 |
|
|
|
17 |
|
|
#ifdef SPEC_RGB |
18 |
|
|
/* |
19 |
|
|
* The following table contains the CIE tristimulus integrals |
20 |
|
|
* for X, Y, and Z. The table is cumulative, so that |
21 |
|
|
* each color coordinate integrates to 1. |
22 |
|
|
*/ |
23 |
|
|
|
24 |
|
|
#define STARTWL 380 /* starting wavelength (nanometers) */ |
25 |
|
|
#define INCWL 10 /* wavelength increment */ |
26 |
|
|
#define NINC 40 /* # of values */ |
27 |
|
|
|
28 |
|
|
static BYTE chroma[3][NINC] = { |
29 |
|
|
{ /* X */ |
30 |
|
|
0, 0, 0, 2, 6, 13, 22, 30, 36, 41, |
31 |
|
|
42, 43, 43, 44, 46, 52, 60, 71, 87, 106, |
32 |
|
|
128, 153, 178, 200, 219, 233, 243, 249, 252, 254, |
33 |
|
|
255, 255, 255, 255, 255, 255, 255, 255, 255, 255 |
34 |
|
|
}, { /* Y */ |
35 |
|
|
0, 0, 0, 0, 0, 1, 2, 4, 7, 11, |
36 |
|
|
17, 24, 34, 48, 64, 84, 105, 127, 148, 169, |
37 |
|
|
188, 205, 220, 232, 240, 246, 250, 253, 254, 255, |
38 |
|
|
255, 255, 255, 255, 255, 255, 255, 255, 255, 255 |
39 |
|
|
}, { /* Z */ |
40 |
|
|
0, 0, 2, 10, 32, 66, 118, 153, 191, 220, |
41 |
|
|
237, 246, 251, 253, 254, 255, 255, 255, 255, 255, |
42 |
|
|
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, |
43 |
|
|
255, 255, 255, 255, 255, 255, 255, 255, 255, 255 |
44 |
|
|
} |
45 |
|
|
}; |
46 |
|
|
|
47 |
|
|
|
48 |
|
|
spec_rgb(col, s, e) /* comput RGB color from spectral range */ |
49 |
|
|
COLOR col; |
50 |
|
|
int s, e; |
51 |
|
|
{ |
52 |
|
|
COLOR ciecolor; |
53 |
|
|
|
54 |
|
|
spec_cie(ciecolor, s, e); |
55 |
|
|
cie_rgb(col, ciecolor); |
56 |
|
|
} |
57 |
|
|
|
58 |
|
|
|
59 |
|
|
spec_cie(col, s, e) /* compute a color from a spectral range */ |
60 |
|
|
COLOR col; /* returned color */ |
61 |
|
|
int s, e; /* starting and ending wavelengths */ |
62 |
|
|
{ |
63 |
|
|
register int i, d, r; |
64 |
|
|
|
65 |
|
|
s -= STARTWL; |
66 |
|
|
if (s < 0) |
67 |
|
|
s = 0; |
68 |
|
|
|
69 |
|
|
e -= STARTWL; |
70 |
|
|
if (e >= INCWL*(NINC - 1)) |
71 |
|
|
e = INCWL*(NINC - 1) - 1; |
72 |
|
|
|
73 |
|
|
d = e / INCWL; /* interpolate values */ |
74 |
|
|
r = e % INCWL; |
75 |
|
|
for (i = 0; i < 3; i++) |
76 |
|
|
col[i] = chroma[i][d]*(INCWL - r) + chroma[i][d + 1]*r; |
77 |
|
|
|
78 |
|
|
d = s / INCWL; |
79 |
|
|
r = s % INCWL; |
80 |
|
|
for (i = 0; i < 3; i++) |
81 |
|
|
col[i] -= chroma[i][d]*(INCWL - r) - chroma[i][d + 1]*r; |
82 |
|
|
|
83 |
|
|
col[RED] = (col[RED] + 0.5) / (256*INCWL); |
84 |
|
|
col[GRN] = (col[GRN] + 0.5) / (256*INCWL); |
85 |
|
|
col[BLU] = (col[BLU] + 0.5) / (256*INCWL); |
86 |
|
|
} |
87 |
|
|
|
88 |
|
|
|
89 |
|
|
cie_rgb(rgbcolor, ciecolor) /* convert CIE to RGB (NTSC) */ |
90 |
|
|
register COLOR rgbcolor, ciecolor; |
91 |
|
|
{ |
92 |
|
|
static float cmat[3][3] = { |
93 |
|
|
1.73, -.48, -.26, |
94 |
|
|
-.81, 1.65, -.02, |
95 |
|
|
.08, -.17, 1.28, |
96 |
|
|
}; |
97 |
|
|
register int i; |
98 |
|
|
|
99 |
|
|
for (i = 0; i < 3; i++) { |
100 |
|
|
rgbcolor[i] = cmat[i][0]*ciecolor[0] + |
101 |
|
|
cmat[i][1]*ciecolor[1] + |
102 |
|
|
cmat[i][2]*ciecolor[2] ; |
103 |
|
|
if (rgbcolor[i] < 0.0) |
104 |
|
|
rgbcolor[i] = 0.0; |
105 |
|
|
} |
106 |
|
|
} |
107 |
|
|
#endif |
108 |
|
|
|
109 |
|
|
|
110 |
greg |
1.5 |
fputresolu(ord, xres, yres, fp) /* put x and y resolution */ |
111 |
|
|
register int ord; |
112 |
|
|
int xres, yres; |
113 |
|
|
FILE *fp; |
114 |
|
|
{ |
115 |
|
|
if (ord&YMAJOR) |
116 |
|
|
fprintf(fp, "%cY %d %cX %d\n", |
117 |
|
|
ord&YDECR ? '-' : '+', yres, |
118 |
|
|
ord&XDECR ? '-' : '+', xres); |
119 |
|
|
else |
120 |
|
|
fprintf(fp, "%cX %d %cY %d\n", |
121 |
|
|
ord&XDECR ? '-' : '+', xres, |
122 |
|
|
ord&YDECR ? '-' : '+', yres); |
123 |
|
|
} |
124 |
|
|
|
125 |
|
|
|
126 |
|
|
fgetresolu(xrp, yrp, fp) /* get x and y resolution */ |
127 |
|
|
int *xrp, *yrp; |
128 |
|
|
FILE *fp; |
129 |
|
|
{ |
130 |
|
|
char buf[64], *xndx, *yndx; |
131 |
|
|
register char *cp; |
132 |
|
|
register int ord; |
133 |
|
|
|
134 |
|
|
if (fgets(buf, sizeof(buf), fp) == NULL) |
135 |
|
|
return(-1); |
136 |
|
|
xndx = yndx = NULL; |
137 |
|
|
for (cp = buf+1; *cp; cp++) |
138 |
|
|
if (*cp == 'X') |
139 |
|
|
xndx = cp; |
140 |
|
|
else if (*cp == 'Y') |
141 |
|
|
yndx = cp; |
142 |
|
|
if (xndx == NULL || yndx == NULL) |
143 |
|
|
return(-1); |
144 |
|
|
ord = 0; |
145 |
|
|
if (xndx > yndx) ord |= YMAJOR; |
146 |
|
|
if (xndx[-1] == '-') ord |= XDECR; |
147 |
|
|
if (yndx[-1] == '-') ord |= YDECR; |
148 |
|
|
if ((*xrp = atoi(xndx+1)) <= 0) |
149 |
|
|
return(-1); |
150 |
|
|
if ((*yrp = atoi(yndx+1)) <= 0) |
151 |
|
|
return(-1); |
152 |
|
|
return(ord); |
153 |
|
|
} |
154 |
|
|
|
155 |
|
|
|
156 |
greg |
1.1 |
fwritecolrs(scanline, len, fp) /* write out a colr scanline */ |
157 |
|
|
register COLR *scanline; |
158 |
|
|
int len; |
159 |
|
|
register FILE *fp; |
160 |
|
|
{ |
161 |
|
|
COLR lastcolr; |
162 |
|
|
int rept; |
163 |
|
|
|
164 |
|
|
lastcolr[RED] = lastcolr[GRN] = lastcolr[BLU] = 1; |
165 |
|
|
lastcolr[EXP] = 0; |
166 |
|
|
rept = 0; |
167 |
|
|
|
168 |
|
|
while (len > 0) { |
169 |
|
|
if (scanline[0][EXP] == lastcolr[EXP] && |
170 |
|
|
scanline[0][RED] == lastcolr[RED] && |
171 |
|
|
scanline[0][GRN] == lastcolr[GRN] && |
172 |
|
|
scanline[0][BLU] == lastcolr[BLU]) |
173 |
|
|
rept++; |
174 |
|
|
else { |
175 |
|
|
while (rept) { /* write out count */ |
176 |
|
|
putc(1, fp); |
177 |
|
|
putc(1, fp); |
178 |
|
|
putc(1, fp); |
179 |
|
|
putc(rept & 255, fp); |
180 |
|
|
rept >>= 8; |
181 |
|
|
} |
182 |
|
|
putc(scanline[0][RED], fp); /* new color */ |
183 |
|
|
putc(scanline[0][GRN], fp); |
184 |
|
|
putc(scanline[0][BLU], fp); |
185 |
|
|
putc(scanline[0][EXP], fp); |
186 |
|
|
copycolr(lastcolr, scanline[0]); |
187 |
|
|
rept = 0; |
188 |
|
|
} |
189 |
|
|
scanline++; |
190 |
|
|
len--; |
191 |
|
|
} |
192 |
|
|
while (rept) { /* write out count */ |
193 |
|
|
putc(1, fp); |
194 |
|
|
putc(1, fp); |
195 |
|
|
putc(1, fp); |
196 |
|
|
putc(rept & 255, fp); |
197 |
|
|
rept >>= 8; |
198 |
|
|
} |
199 |
|
|
return(ferror(fp) ? -1 : 0); |
200 |
|
|
} |
201 |
|
|
|
202 |
|
|
|
203 |
|
|
freadcolrs(scanline, len, fp) /* read in a colr scanline */ |
204 |
|
|
register COLR *scanline; |
205 |
|
|
int len; |
206 |
|
|
register FILE *fp; |
207 |
|
|
{ |
208 |
|
|
int rshift; |
209 |
|
|
register int i; |
210 |
|
|
|
211 |
|
|
rshift = 0; |
212 |
|
|
|
213 |
|
|
while (len > 0) { |
214 |
|
|
scanline[0][RED] = getc(fp); |
215 |
|
|
scanline[0][GRN] = getc(fp); |
216 |
|
|
scanline[0][BLU] = getc(fp); |
217 |
|
|
scanline[0][EXP] = getc(fp); |
218 |
|
|
if (feof(fp) || ferror(fp)) |
219 |
|
|
return(-1); |
220 |
|
|
if (scanline[0][RED] == 1 && |
221 |
|
|
scanline[0][GRN] == 1 && |
222 |
|
|
scanline[0][BLU] == 1) { |
223 |
|
|
for (i = scanline[0][EXP] << rshift; i > 0; i--) { |
224 |
|
|
copycolr(scanline[0], scanline[-1]); |
225 |
|
|
scanline++; |
226 |
|
|
len--; |
227 |
|
|
} |
228 |
|
|
rshift += 8; |
229 |
|
|
} else { |
230 |
|
|
scanline++; |
231 |
|
|
len--; |
232 |
|
|
rshift = 0; |
233 |
|
|
} |
234 |
|
|
} |
235 |
|
|
return(0); |
236 |
|
|
} |
237 |
|
|
|
238 |
|
|
|
239 |
|
|
fwritescan(scanline, len, fp) /* write out a scanline */ |
240 |
|
|
register COLOR *scanline; |
241 |
|
|
int len; |
242 |
|
|
register FILE *fp; |
243 |
|
|
{ |
244 |
|
|
COLR lastcolr, thiscolr; |
245 |
|
|
int rept; |
246 |
|
|
|
247 |
|
|
lastcolr[RED] = lastcolr[GRN] = lastcolr[BLU] = 1; |
248 |
|
|
lastcolr[EXP] = 0; |
249 |
|
|
rept = 0; |
250 |
|
|
|
251 |
|
|
while (len > 0) { |
252 |
|
|
setcolr(thiscolr, scanline[0][RED], |
253 |
|
|
scanline[0][GRN], |
254 |
|
|
scanline[0][BLU]); |
255 |
|
|
if (thiscolr[EXP] == lastcolr[EXP] && |
256 |
|
|
thiscolr[RED] == lastcolr[RED] && |
257 |
|
|
thiscolr[GRN] == lastcolr[GRN] && |
258 |
|
|
thiscolr[BLU] == lastcolr[BLU]) |
259 |
|
|
rept++; |
260 |
|
|
else { |
261 |
|
|
while (rept) { /* write out count */ |
262 |
|
|
putc(1, fp); |
263 |
|
|
putc(1, fp); |
264 |
|
|
putc(1, fp); |
265 |
|
|
putc(rept & 255, fp); |
266 |
|
|
rept >>= 8; |
267 |
|
|
} |
268 |
|
|
putc(thiscolr[RED], fp); /* new color */ |
269 |
|
|
putc(thiscolr[GRN], fp); |
270 |
|
|
putc(thiscolr[BLU], fp); |
271 |
|
|
putc(thiscolr[EXP], fp); |
272 |
|
|
copycolr(lastcolr, thiscolr); |
273 |
|
|
rept = 0; |
274 |
|
|
} |
275 |
|
|
scanline++; |
276 |
|
|
len--; |
277 |
|
|
} |
278 |
|
|
while (rept) { /* write out count */ |
279 |
|
|
putc(1, fp); |
280 |
|
|
putc(1, fp); |
281 |
|
|
putc(1, fp); |
282 |
|
|
putc(rept & 255, fp); |
283 |
|
|
rept >>= 8; |
284 |
|
|
} |
285 |
|
|
return(ferror(fp) ? -1 : 0); |
286 |
|
|
} |
287 |
|
|
|
288 |
|
|
|
289 |
|
|
freadscan(scanline, len, fp) /* read in a scanline */ |
290 |
|
|
register COLOR *scanline; |
291 |
|
|
int len; |
292 |
|
|
register FILE *fp; |
293 |
|
|
{ |
294 |
|
|
COLR thiscolr; |
295 |
|
|
int rshift; |
296 |
|
|
register int i; |
297 |
|
|
|
298 |
|
|
rshift = 0; |
299 |
|
|
|
300 |
|
|
while (len > 0) { |
301 |
|
|
thiscolr[RED] = getc(fp); |
302 |
|
|
thiscolr[GRN] = getc(fp); |
303 |
|
|
thiscolr[BLU] = getc(fp); |
304 |
|
|
thiscolr[EXP] = getc(fp); |
305 |
|
|
if (feof(fp) || ferror(fp)) |
306 |
|
|
return(-1); |
307 |
|
|
if (thiscolr[RED] == 1 && |
308 |
|
|
thiscolr[GRN] == 1 && |
309 |
|
|
thiscolr[BLU] == 1) { |
310 |
|
|
for (i = thiscolr[EXP] << rshift; i > 0; i--) { |
311 |
|
|
copycolor(scanline[0], scanline[-1]); |
312 |
|
|
scanline++; |
313 |
|
|
len--; |
314 |
|
|
} |
315 |
|
|
rshift += 8; |
316 |
|
|
} else { |
317 |
|
|
colr_color(scanline[0], thiscolr); |
318 |
|
|
scanline++; |
319 |
|
|
len--; |
320 |
|
|
rshift = 0; |
321 |
|
|
} |
322 |
|
|
} |
323 |
|
|
return(0); |
324 |
|
|
} |
325 |
|
|
|
326 |
|
|
|
327 |
|
|
setcolr(clr, r, g, b) /* assign a short color value */ |
328 |
|
|
register COLR clr; |
329 |
|
|
double r, g, b; |
330 |
|
|
{ |
331 |
|
|
double frexp(); |
332 |
|
|
double d; |
333 |
|
|
int e; |
334 |
|
|
|
335 |
|
|
d = r > g ? r : g; |
336 |
|
|
if (b > d) d = b; |
337 |
|
|
|
338 |
greg |
1.4 |
if (d <= 1e-32) { |
339 |
greg |
1.1 |
clr[RED] = clr[GRN] = clr[BLU] = 0; |
340 |
|
|
clr[EXP] = 0; |
341 |
|
|
return; |
342 |
|
|
} |
343 |
|
|
|
344 |
|
|
d = frexp(d, &e) * 256.0 / d; |
345 |
|
|
|
346 |
|
|
clr[RED] = r * d; |
347 |
|
|
clr[GRN] = g * d; |
348 |
|
|
clr[BLU] = b * d; |
349 |
|
|
clr[EXP] = e + COLXS; |
350 |
|
|
} |
351 |
|
|
|
352 |
|
|
|
353 |
|
|
colr_color(col, clr) /* convert short to float color */ |
354 |
|
|
register COLOR col; |
355 |
|
|
register COLR clr; |
356 |
|
|
{ |
357 |
greg |
1.6 |
double f; |
358 |
greg |
1.1 |
|
359 |
|
|
if (clr[EXP] == 0) |
360 |
|
|
col[RED] = col[GRN] = col[BLU] = 0.0; |
361 |
|
|
else { |
362 |
greg |
1.2 |
f = ldexp(1.0, (int)clr[EXP]-(COLXS+8)); |
363 |
greg |
1.1 |
col[RED] = (clr[RED] + 0.5)*f; |
364 |
|
|
col[GRN] = (clr[GRN] + 0.5)*f; |
365 |
|
|
col[BLU] = (clr[BLU] + 0.5)*f; |
366 |
|
|
} |
367 |
greg |
1.6 |
} |
368 |
|
|
|
369 |
|
|
|
370 |
|
|
int |
371 |
|
|
colr_norm(clr, nclr) /* normalize a short color, return shift */ |
372 |
|
|
COLR clr, nclr; |
373 |
|
|
{ |
374 |
|
|
register int c; |
375 |
|
|
register int shift = clr[EXP]-COLXS; |
376 |
|
|
|
377 |
|
|
if (shift > 0) { |
378 |
|
|
if (shift >= 8) { |
379 |
|
|
nclr[RED] = nclr[GRN] = nclr[BLU] = 255; |
380 |
|
|
} else { |
381 |
|
|
c = clr[RED] << shift; |
382 |
|
|
nclr[RED] = c > 255 ? 255 : c; |
383 |
|
|
c = clr[GRN] << shift; |
384 |
|
|
nclr[GRN] = c > 255 ? 255 : c; |
385 |
|
|
c = clr[BLU] << shift; |
386 |
|
|
nclr[BLU] = c > 255 ? 255 : c; |
387 |
|
|
} |
388 |
|
|
} else if (shift < 0) { |
389 |
|
|
if (shift <= -8) { |
390 |
|
|
nclr[RED] = nclr[GRN] = nclr[BLU] = 0; |
391 |
|
|
} else { |
392 |
|
|
nclr[RED] = clr[RED] >> -shift; |
393 |
|
|
nclr[GRN] = clr[GRN] >> -shift; |
394 |
|
|
nclr[BLU] = clr[BLU] >> -shift; |
395 |
|
|
} |
396 |
|
|
} else { |
397 |
|
|
nclr[RED] = clr[RED]; |
398 |
|
|
nclr[GRN] = clr[GRN]; |
399 |
|
|
nclr[BLU] = clr[BLU]; |
400 |
|
|
} |
401 |
|
|
nclr[EXP] = COLXS; |
402 |
|
|
return(shift); |
403 |
greg |
1.1 |
} |
404 |
greg |
1.7 |
|
405 |
|
|
|
406 |
|
|
bigdiff(c1, c2, md) /* c1 delta c2 > md? */ |
407 |
|
|
register COLOR c1, c2; |
408 |
|
|
double md; |
409 |
|
|
{ |
410 |
|
|
register int i; |
411 |
|
|
|
412 |
|
|
for (i = 0; i < 3; i++) |
413 |
|
|
if (colval(c1,i)-colval(c2,i) > md*colval(c2,i) || |
414 |
|
|
colval(c2,i)-colval(c1,i) > md*colval(c1,i)) |
415 |
|
|
return(1); |
416 |
|
|
return(0); |
417 |
|
|
} |