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root/radiance/ray/src/common/tonemap.c
Revision: 3.22
Committed: Thu Mar 23 22:01:43 2006 UTC (18 years, 1 month ago) by greg
Content type: text/plain
Branch: MAIN
Changes since 3.21: +6 -1 lines
Log Message:
Fixed problems with NaN and Inf floating point color values

File Contents

# Content
1 #ifndef lint
2 static const char RCSid[] = "$Id: tonemap.c,v 3.21 2006/01/18 00:24:38 greg Exp $";
3 #endif
4 /*
5 * Tone mapping functions.
6 * See tonemap.h for detailed function descriptions.
7 * Added von Kries white-balance calculations 10/01 (GW).
8 *
9 * Externals declared in tonemap.h
10 */
11
12 #include "copyright.h"
13
14 #include <stdio.h>
15 #include <math.h>
16 #include "tmprivat.h"
17 #include "tmerrmsg.h"
18
19 #define exp10(x) exp(M_LN10*(x))
20
21 /* our list of conversion packages */
22 struct tmPackage *tmPkg[TM_MAXPKG];
23 int tmNumPkgs = 0; /* number of registered packages */
24
25
26 TMstruct *
27 tmInit( /* initialize new tone mapping */
28 int flags,
29 RGBPRIMP monpri,
30 double gamval
31 )
32 {
33 COLORMAT cmat;
34 TMstruct *tmnew;
35 int i;
36 /* allocate structure */
37 tmnew = (TMstruct *)malloc(sizeof(TMstruct));
38 if (tmnew == NULL)
39 return(NULL);
40
41 tmnew->flags = flags & ~TM_F_UNIMPL;
42 if (tmnew->flags & TM_F_BW)
43 tmnew->flags &= ~TM_F_MESOPIC;
44 /* set monitor transform */
45 if (monpri == NULL || monpri == stdprims || tmnew->flags & TM_F_BW) {
46 tmnew->monpri = stdprims;
47 tmnew->clf[RED] = rgb2xyzmat[1][0];
48 tmnew->clf[GRN] = rgb2xyzmat[1][1];
49 tmnew->clf[BLU] = rgb2xyzmat[1][2];
50 } else {
51 comprgb2xyzWBmat(cmat, tmnew->monpri=monpri);
52 tmnew->clf[RED] = cmat[1][0];
53 tmnew->clf[GRN] = cmat[1][1];
54 tmnew->clf[BLU] = cmat[1][2];
55 }
56 /* set gamma value */
57 if (gamval < MINGAM)
58 tmnew->mongam = DEFGAM;
59 else
60 tmnew->mongam = gamval;
61 /* set color divisors */
62 for (i = 0; i < 3; i++)
63 tmnew->cdiv[i] = 256.*pow(tmnew->clf[i], 1./tmnew->mongam);
64
65 /* set input transform */
66 tmnew->inppri = tmnew->monpri;
67 tmnew->cmat[0][0] = tmnew->cmat[1][1] = tmnew->cmat[2][2] =
68 tmnew->inpsf = WHTEFFICACY;
69 tmnew->cmat[0][1] = tmnew->cmat[0][2] = tmnew->cmat[1][0] =
70 tmnew->cmat[1][2] = tmnew->cmat[2][0] = tmnew->cmat[2][1] = 0.;
71 tmnew->inpdat = NULL;
72 tmnew->hbrmin = 10; tmnew->hbrmax = -10;
73 tmnew->histo = NULL;
74 tmnew->mbrmin = 10; tmnew->mbrmax = -10;
75 tmnew->lumap = NULL;
76 /* zero private data */
77 for (i = TM_MAXPKG; i--; )
78 tmnew->pd[i] = NULL;
79 tmnew->lastError = TM_E_OK;
80 tmnew->lastFunc = "NoErr";
81 /* return new TMstruct */
82 return(tmnew);
83 }
84
85
86 int
87 tmSetSpace( /* set input color space for conversions */
88 TMstruct *tms,
89 RGBPRIMP pri,
90 double sf,
91 MEM_PTR dat
92 )
93 {
94 static const char funcName[] = "tmSetSpace";
95 int i, j;
96 /* error check */
97 if (tms == NULL)
98 returnErr(TM_E_TMINVAL);
99 if (sf <= 1e-12)
100 returnErr(TM_E_ILLEGAL);
101 /* check if no change */
102 if (pri == tms->inppri && FEQ(sf, tms->inpsf) && dat == tms->inpdat)
103 returnOK;
104 tms->inppri = pri; /* let's set it */
105 tms->inpsf = sf;
106 tms->inpdat = dat;
107
108 if (tms->flags & TM_F_BW) { /* color doesn't matter */
109 tms->monpri = tms->inppri; /* eliminate xform */
110 if (tms->inppri == TM_XYZPRIM) {
111 tms->clf[CIEX] = tms->clf[CIEZ] = 0.;
112 tms->clf[CIEY] = 1.;
113 } else {
114 comprgb2xyzWBmat(tms->cmat, tms->monpri);
115 tms->clf[RED] = tms->cmat[1][0];
116 tms->clf[GRN] = tms->cmat[1][1];
117 tms->clf[BLU] = tms->cmat[1][2];
118 }
119 tms->cmat[0][0] = tms->cmat[1][1] = tms->cmat[2][2] =
120 tms->inpsf;
121 tms->cmat[0][1] = tms->cmat[0][2] = tms->cmat[1][0] =
122 tms->cmat[1][2] = tms->cmat[2][0] = tms->cmat[2][1] = 0.;
123
124 } else if (tms->inppri == TM_XYZPRIM) /* input is XYZ */
125 compxyz2rgbWBmat(tms->cmat, tms->monpri);
126
127 else { /* input is RGB */
128 if (tms->inppri != tms->monpri &&
129 PRIMEQ(tms->inppri, tms->monpri))
130 tms->inppri = tms->monpri; /* no xform */
131 comprgb2rgbWBmat(tms->cmat, tms->inppri, tms->monpri);
132 }
133 for (i = 0; i < 3; i++)
134 for (j = 0; j < 3; j++)
135 tms->cmat[i][j] *= tms->inpsf;
136 /* set color divisors */
137 for (i = 0; i < 3; i++)
138 if (tms->clf[i] > .001)
139 tms->cdiv[i] =
140 256.*pow(tms->clf[i], 1./tms->mongam);
141 else
142 tms->cdiv[i] = 1;
143 /* notify packages */
144 for (i = tmNumPkgs; i--; )
145 if (tms->pd[i] != NULL && tmPkg[i]->NewSpace != NULL)
146 (*tmPkg[i]->NewSpace)(tms);
147 returnOK;
148 }
149
150
151 void
152 tmClearHisto( /* clear current histogram */
153 TMstruct *tms
154 )
155 {
156 if (tms == NULL || tms->histo == NULL)
157 return;
158 free((MEM_PTR)tms->histo);
159 tms->histo = NULL;
160 }
161
162
163 int
164 tmCvColors( /* convert float colors */
165 TMstruct *tms,
166 TMbright *ls,
167 BYTE *cs,
168 COLOR *scan,
169 int len
170 )
171 {
172 static const char funcName[] = "tmCvColors";
173 static COLOR csmall = {.5*MINLUM, .5*MINLUM, .5*MINLUM};
174 static BYTE gamtab[1024];
175 static double curgam = .0;
176 COLOR cmon;
177 double lum, slum;
178 double d;
179 int i;
180
181 if (tms == NULL)
182 returnErr(TM_E_TMINVAL);
183 if ((ls == NULL) | (scan == NULL) | (len < 0))
184 returnErr(TM_E_ILLEGAL);
185 if (cs != TM_NOCHROM && fabs(tms->mongam - curgam) > .02) {
186 curgam = tms->mongam; /* (re)build table */
187 for (i = 1024; i--; )
188 gamtab[i] = (int)(256.*pow((i+.5)/1024., 1./curgam));
189 }
190 for (i = len; i--; ) {
191 if (tmNeedMatrix(tms)) { /* get monitor RGB */
192 colortrans(cmon, tms->cmat, scan[i]);
193 } else {
194 cmon[RED] = tms->inpsf*scan[i][RED];
195 cmon[GRN] = tms->inpsf*scan[i][GRN];
196 cmon[BLU] = tms->inpsf*scan[i][BLU];
197 }
198 #ifdef isnan
199 if (isnan(cmon[RED]) || isinf(cmon[RED])) cmon[RED] = .0f;
200 if (isnan(cmon[GRN]) || isinf(cmon[GRN])) cmon[GRN] = .0f;
201 if (isnan(cmon[BLU]) || isinf(cmon[BLU])) cmon[BLU] = .0f;
202 #endif
203 /* world luminance */
204 lum = tms->clf[RED]*cmon[RED] +
205 tms->clf[GRN]*cmon[GRN] +
206 tms->clf[BLU]*cmon[BLU] ;
207 /* check range */
208 if (clipgamut(cmon, lum, CGAMUT_LOWER, csmall, cwhite))
209 lum = tms->clf[RED]*cmon[RED] +
210 tms->clf[GRN]*cmon[GRN] +
211 tms->clf[BLU]*cmon[BLU] ;
212 if (lum < MINLUM) {
213 ls[i] = MINBRT-1; /* bogus value */
214 lum = MINLUM;
215 } else {
216 d = TM_BRTSCALE*log(lum); /* encode it */
217 ls[i] = d>0. ? (int)(d+.5) : (int)(d-.5);
218 }
219 if (cs == TM_NOCHROM) /* no color? */
220 continue;
221 if (tms->flags & TM_F_MESOPIC && lum < LMESUPPER) {
222 slum = scotlum(cmon); /* mesopic adj. */
223 if (lum < LMESLOWER)
224 cmon[RED] = cmon[GRN] = cmon[BLU] = slum;
225 else {
226 d = (lum - LMESLOWER)/(LMESUPPER - LMESLOWER);
227 if (tms->flags & TM_F_BW)
228 cmon[RED] = cmon[GRN] =
229 cmon[BLU] = d*lum;
230 else
231 scalecolor(cmon, d);
232 d = (1.-d)*slum;
233 cmon[RED] += d;
234 cmon[GRN] += d;
235 cmon[BLU] += d;
236 }
237 } else if (tms->flags & TM_F_BW) {
238 cmon[RED] = cmon[GRN] = cmon[BLU] = lum;
239 }
240 d = tms->clf[RED]*cmon[RED]/lum;
241 cs[3*i ] = d>=.999 ? 255 : gamtab[(int)(1024.*d)];
242 d = tms->clf[GRN]*cmon[GRN]/lum;
243 cs[3*i+1] = d>=.999 ? 255 : gamtab[(int)(1024.*d)];
244 d = tms->clf[BLU]*cmon[BLU]/lum;
245 cs[3*i+2] = d>=.999 ? 255 : gamtab[(int)(1024.*d)];
246 }
247 returnOK;
248 }
249
250
251 TMbright
252 tmCvLuminance( /* convert a single luminance */
253 double lum
254 )
255 {
256 double d;
257
258 if (lum <= TM_NOLUM)
259 return(TM_NOBRT);
260 d = TM_BRTSCALE*log(lum);
261 if (d > 0.)
262 return((TMbright)(d+.5));
263 return((TMbright)(d-.5));
264 }
265
266
267 int
268 tmCvGrays( /* convert float gray values */
269 TMstruct *tms,
270 TMbright *ls,
271 float *scan,
272 int len
273 )
274 {
275 static const char funcName[] = "tmCvGrays";
276 double d;
277 int i;
278
279 if (tms == NULL)
280 returnErr(TM_E_TMINVAL);
281 if ((ls == NULL) | (scan == NULL) | (len < 0))
282 returnErr(TM_E_ILLEGAL);
283 for (i = len; i--; )
284 if (scan[i] <= TM_NOLUM) {
285 ls[i] = TM_NOBRT; /* bogus value */
286 } else {
287 d = TM_BRTSCALE*log(scan[i]); /* encode it */
288 ls[i] = d>0. ? (int)(d+.5) : (int)(d-.5);
289 }
290 returnOK;
291 }
292
293
294 int
295 tmAddHisto( /* add values to histogram */
296 TMstruct *tms,
297 TMbright *ls,
298 int len,
299 int wt
300 )
301 {
302 static const char funcName[] = "tmAddHisto";
303 int oldorig=0, oldlen, horig, hlen;
304 int i, j;
305
306 if (tms == NULL)
307 returnErr(TM_E_TMINVAL);
308 if (len < 0)
309 returnErr(TM_E_ILLEGAL);
310 if (len == 0)
311 returnOK;
312 /* first, grow limits */
313 if (tms->histo == NULL) {
314 for (i = len; i-- && ls[i] < MINBRT; )
315 ;
316 if (i < 0)
317 returnOK;
318 tms->hbrmin = tms->hbrmax = ls[i];
319 oldlen = 0;
320 } else {
321 oldorig = (tms->hbrmin-MINBRT)/HISTEP;
322 oldlen = (tms->hbrmax-MINBRT)/HISTEP + 1 - oldorig;
323 }
324 for (i = len; i--; ) {
325 if ((j = ls[i]) < MINBRT)
326 continue;
327 if (j < tms->hbrmin)
328 tms->hbrmin = j;
329 else if (j > tms->hbrmax)
330 tms->hbrmax = j;
331 }
332 horig = (tms->hbrmin-MINBRT)/HISTEP;
333 hlen = (tms->hbrmax-MINBRT)/HISTEP + 1 - horig;
334 if (hlen > oldlen) { /* (re)allocate histogram */
335 int *newhist = (int *)calloc(hlen, sizeof(int));
336 if (newhist == NULL)
337 returnErr(TM_E_NOMEM);
338 if (oldlen) { /* copy and free old */
339 for (i = oldlen, j = i+oldorig-horig; i; )
340 newhist[--j] = tms->histo[--i];
341 free((MEM_PTR)tms->histo);
342 }
343 tms->histo = newhist;
344 }
345 if (wt == 0)
346 returnOK;
347 for (i = len; i--; ) /* add in new counts */
348 if (ls[i] >= MINBRT)
349 tms->histo[ (ls[i]-MINBRT)/HISTEP - horig ] += wt;
350 returnOK;
351 }
352
353
354 static double
355 htcontrs( /* human threshold contrast sensitivity, dL(La) */
356 double La
357 )
358 {
359 double l10La, l10dL;
360 /* formula taken from Ferwerda et al. [SG96] */
361 if (La < 1.148e-4)
362 return(1.38e-3);
363 l10La = log10(La);
364 if (l10La < -1.44) /* rod response regime */
365 l10dL = pow(.405*l10La + 1.6, 2.18) - 2.86;
366 else if (l10La < -.0184)
367 l10dL = l10La - .395;
368 else if (l10La < 1.9) /* cone response regime */
369 l10dL = pow(.249*l10La + .65, 2.7) - .72;
370 else
371 l10dL = l10La - 1.255;
372
373 return(exp10(l10dL));
374 }
375
376
377 static int
378 tmNewMap( /* allocate new tone-mapping array */
379 TMstruct *tms
380 )
381 {
382 if (tms->lumap != NULL && (tms->mbrmax - tms->mbrmin) !=
383 (tms->hbrmax - tms->hbrmin)) {
384 free((MEM_PTR)tms->lumap);
385 tms->lumap = NULL;
386 }
387 tms->mbrmin = tms->hbrmin;
388 tms->mbrmax = tms->hbrmax;
389 if (tms->mbrmin > tms->mbrmax)
390 return 0;
391 if (tms->lumap == NULL)
392 tms->lumap = (unsigned short *)malloc(sizeof(unsigned short)*
393 (tms->mbrmax-tms->mbrmin+1));
394 return(tms->lumap != NULL);
395 }
396
397
398 int
399 tmFixedMapping( /* compute fixed, linear tone-mapping */
400 TMstruct *tms,
401 double expmult,
402 double gamval
403 )
404 {
405 static const char funcName[] = "tmFixedMapping";
406 double d;
407 int i;
408
409 if (!tmNewMap(tms))
410 returnErr(TM_E_NOMEM);
411 if (expmult <= .0)
412 expmult = 1.;
413 if (gamval < MINGAM)
414 gamval = tms->mongam;
415 d = log(expmult/tms->inpsf);
416 for (i = tms->mbrmax-tms->mbrmin+1; i--; )
417 tms->lumap[i] = 256. * exp(
418 ( d + (tms->mbrmin+i)*(1./TM_BRTSCALE) )
419 / gamval );
420 returnOK;
421 }
422
423
424 int
425 tmComputeMapping( /* compute histogram tone-mapping */
426 TMstruct *tms,
427 double gamval,
428 double Lddyn,
429 double Ldmax
430 )
431 {
432 static const char funcName[] = "tmComputeMapping";
433 int *histo;
434 float *cumf;
435 int brt0, histlen, threshold, ceiling, trimmings;
436 double logLddyn, Ldmin, Ldavg, Lwavg, Tr, Lw, Ld;
437 int32 histot;
438 double sum;
439 double d;
440 int i, j;
441
442 if (tms == NULL || tms->histo == NULL)
443 returnErr(TM_E_TMINVAL);
444 /* check arguments */
445 if (Lddyn < MINLDDYN) Lddyn = DEFLDDYN;
446 if (Ldmax < MINLDMAX) Ldmax = DEFLDMAX;
447 if (gamval < MINGAM) gamval = tms->mongam;
448 /* compute handy values */
449 Ldmin = Ldmax/Lddyn;
450 logLddyn = log(Lddyn);
451 Ldavg = sqrt(Ldmax*Ldmin);
452 i = (tms->hbrmin-MINBRT)/HISTEP;
453 brt0 = MINBRT + HISTEP/2 + i*HISTEP;
454 histlen = (tms->hbrmax-MINBRT)/HISTEP + 1 - i;
455 /* histogram total and mean */
456 histot = 0; sum = 0;
457 j = brt0 + histlen*HISTEP;
458 for (i = histlen; i--; ) {
459 histot += tms->histo[i];
460 sum += (j -= HISTEP) * tms->histo[i];
461 }
462 threshold = histot*0.005 + .5;
463 if (threshold < 4)
464 returnErr(TM_E_TMFAIL);
465 Lwavg = tmLuminance( (double)sum / histot );
466 /* allocate space for mapping */
467 if (!tmNewMap(tms))
468 returnErr(TM_E_NOMEM);
469 /* use linear tone mapping? */
470 if (tms->flags & TM_F_LINEAR)
471 goto linearmap;
472 /* clamp histogram */
473 histo = (int *)malloc(histlen*sizeof(int));
474 cumf = (float *)malloc((histlen+2)*sizeof(float));
475 if ((histo == NULL) | (cumf == NULL))
476 returnErr(TM_E_NOMEM);
477 cumf[histlen+1] = 1.; /* guard for assignment code */
478 for (i = histlen; i--; ) /* make malleable copy */
479 histo[i] = tms->histo[i];
480 do { /* iterate to solution */
481 sum = 0; /* cumulative probability */
482 for (i = 0; i < histlen; i++) {
483 cumf[i] = (double)sum/histot;
484 sum += histo[i];
485 }
486 cumf[histlen] = 1.;
487 Tr = histot * (double)(tms->hbrmax - tms->hbrmin) /
488 ((double)histlen*TM_BRTSCALE) / logLddyn;
489 ceiling = Tr + 1.;
490 trimmings = 0; /* clip to envelope */
491 for (i = histlen; i--; ) {
492 if (tms->flags & TM_F_HCONTR) {
493 Lw = tmLuminance(brt0 + i*HISTEP);
494 Ld = Ldmin * exp( logLddyn *
495 .5*(cumf[i]+cumf[i+1]) );
496 ceiling = Tr * (htcontrs(Ld) * Lw) /
497 (htcontrs(Lw) * Ld) + 1.;
498 }
499 if (histo[i] > ceiling) {
500 trimmings += histo[i] - ceiling;
501 histo[i] = ceiling;
502 }
503 }
504 /* check if we're out of data */
505 if ((histot -= trimmings) <= threshold) {
506 free((MEM_PTR)histo);
507 free((MEM_PTR)cumf);
508 goto linearmap;
509 }
510 } while (trimmings > threshold);
511 /* assign tone-mapping */
512 for (i = tms->mbrmax-tms->mbrmin+1; i--; ) {
513 j = d = (double)i/(tms->mbrmax-tms->mbrmin)*histlen;
514 d -= (double)j;
515 Ld = Ldmin*exp(logLddyn*((1.-d)*cumf[j]+d*cumf[j+1]));
516 d = (Ld - Ldmin)/(Ldmax - Ldmin);
517 tms->lumap[i] = 256.*pow(d, 1./gamval);
518 }
519 free((MEM_PTR)histo); /* clean up and return */
520 free((MEM_PTR)cumf);
521 returnOK;
522 linearmap: /* linear tone-mapping */
523 if (tms->flags & TM_F_HCONTR)
524 d = htcontrs(Ldavg) / htcontrs(Lwavg);
525 else
526 d = Ldavg / Lwavg;
527 return(tmFixedMapping(tms, tms->inpsf*d/Ldmax, gamval));
528 }
529
530
531 int
532 tmMapPixels( /* apply tone-mapping to pixel(s) */
533 TMstruct *tms,
534 BYTE *ps,
535 TMbright *ls,
536 BYTE *cs,
537 int len
538 )
539 {
540 static const char funcName[] = "tmMapPixels";
541 int32 li, pv;
542
543 if (tms == NULL || tms->lumap == NULL)
544 returnErr(TM_E_TMINVAL);
545 if ((ps == NULL) | (ls == NULL) | (len < 0))
546 returnErr(TM_E_ILLEGAL);
547 while (len--) {
548 if ((li = *ls++) < tms->mbrmin) {
549 li = 0;
550 } else {
551 if (li > tms->mbrmax)
552 li = tms->mbrmax;
553 li = tms->lumap[li - tms->mbrmin];
554 }
555 if (cs == TM_NOCHROM)
556 *ps++ = li>255 ? 255 : li;
557 else {
558 pv = *cs++ * li / tms->cdiv[RED];
559 *ps++ = pv>255 ? 255 : pv;
560 pv = *cs++ * li / tms->cdiv[GRN];
561 *ps++ = pv>255 ? 255 : pv;
562 pv = *cs++ * li / tms->cdiv[BLU];
563 *ps++ = pv>255 ? 255 : pv;
564 }
565 }
566 returnOK;
567 }
568
569
570
571
572 TMstruct *
573 tmDup( /* duplicate top tone mapping */
574 TMstruct *tms
575 )
576 {
577 int len;
578 int i;
579 TMstruct *tmnew;
580
581 if (tms == NULL) /* anything to duplicate? */
582 return(NULL);
583 tmnew = (TMstruct *)malloc(sizeof(TMstruct));
584 if (tmnew == NULL)
585 return(NULL);
586 *tmnew = *tms; /* copy everything */
587 if (tmnew->histo != NULL) { /* duplicate histogram */
588 len = (tmnew->hbrmax-MINBRT)/HISTEP + 1 -
589 (tmnew->hbrmin-MINBRT)/HISTEP;
590 tmnew->histo = (int *)malloc(len*sizeof(int));
591 if (tmnew->histo != NULL)
592 for (i = len; i--; )
593 tmnew->histo[i] = tms->histo[i];
594 }
595 if (tmnew->lumap != NULL) { /* duplicate luminance mapping */
596 len = tmnew->mbrmax-tmnew->mbrmin+1;
597 tmnew->lumap = (unsigned short *)malloc(
598 len*sizeof(unsigned short) );
599 if (tmnew->lumap != NULL)
600 for (i = len; i--; )
601 tmnew->lumap[i] = tms->lumap[i];
602 }
603 /* clear package data */
604 for (i = tmNumPkgs; i--; )
605 tmnew->pd[i] = NULL;
606 /* return copy */
607 return(tmnew);
608 }
609
610
611 void
612 tmDone(tms) /* done with tone mapping -- destroy it */
613 TMstruct *tms;
614 {
615 int i;
616 /* NULL arg. is equiv. to tms */
617 if (tms == NULL)
618 return;
619 /* free tables */
620 if (tms->histo != NULL)
621 free((MEM_PTR)tms->histo);
622 if (tms->lumap != NULL)
623 free((MEM_PTR)tms->lumap);
624 /* free private data */
625 for (i = tmNumPkgs; i--; )
626 if (tms->pd[i] != NULL)
627 (*tmPkg[i]->Free)(tms->pd[i]);
628 free((MEM_PTR)tms); /* free basic structure */
629 }
630
631 /******************** Shared but Private library routines *********************/
632
633 BYTE tmMesofact[BMESUPPER-BMESLOWER];
634
635 void
636 tmMkMesofact() /* build mesopic lookup factor table */
637 {
638 int i;
639
640 if (tmMesofact[BMESUPPER-BMESLOWER-1])
641 return;
642
643 for (i = BMESLOWER; i < BMESUPPER; i++)
644 tmMesofact[i-BMESLOWER] = 256. *
645 (tmLuminance(i) - LMESLOWER) /
646 (LMESUPPER - LMESLOWER);
647 }
648
649
650 int
651 tmErrorReturn( /* error return (with message) */
652 const char *func,
653 TMstruct *tms,
654 int err
655 )
656 {
657 if (tms != NULL) {
658 tms->lastFunc = func;
659 tms->lastError = err;
660 if (tms->flags & TM_F_NOSTDERR)
661 return(err);
662 }
663 fputs(func, stderr);
664 fputs(": ", stderr);
665 fputs(tmErrorMessage[err], stderr);
666 fputs("!\n", stderr);
667 return(err);
668 }