| 1 |
/* Copyright (c) 1997 Regents of the University of California */ |
| 2 |
|
| 3 |
#ifndef lint |
| 4 |
static char SCCSid[] = "$SunId$ LBL"; |
| 5 |
#endif |
| 6 |
|
| 7 |
/* |
| 8 |
* Tone mapping functions. |
| 9 |
* See tonemap.h for detailed function descriptions. |
| 10 |
*/ |
| 11 |
|
| 12 |
#include <stdio.h> |
| 13 |
#include <math.h> |
| 14 |
#include "tmprivat.h" |
| 15 |
#include "tmerrmsg.h" |
| 16 |
|
| 17 |
#define exp10(x) exp(M_LN10*(x)) |
| 18 |
|
| 19 |
struct tmStruct *tmTop = NULL; /* current tone mapping stack */ |
| 20 |
|
| 21 |
|
| 22 |
int |
| 23 |
tmErrorReturn(func, err) /* error return (with message) */ |
| 24 |
char *func; |
| 25 |
int err; |
| 26 |
{ |
| 27 |
if (tmTop != NULL && tmTop->flags & TM_F_NOERRS) |
| 28 |
return(err); |
| 29 |
fputs(func, stderr); |
| 30 |
fputs(": ", stderr); |
| 31 |
fputs(tmErrorMessage[err], stderr); |
| 32 |
fputs("!\n", stderr); |
| 33 |
return(err); |
| 34 |
} |
| 35 |
|
| 36 |
|
| 37 |
struct tmStruct * |
| 38 |
tmInit(flags, monpri, gamval) /* initialize new tone mapping */ |
| 39 |
int flags; |
| 40 |
RGBPRIMP monpri; |
| 41 |
double gamval; |
| 42 |
{ |
| 43 |
static char funcName[] = "tmInit"; |
| 44 |
COLORMAT cmat; |
| 45 |
register struct tmStruct *tmnew; |
| 46 |
register int i; |
| 47 |
/* allocate structure */ |
| 48 |
tmnew = (struct tmStruct *)malloc(sizeof(struct tmStruct)); |
| 49 |
if (tmnew == NULL) |
| 50 |
return(NULL); |
| 51 |
|
| 52 |
tmnew->flags = flags & ~TM_F_UNIMPL; |
| 53 |
/* set monitor transform */ |
| 54 |
if (monpri == NULL || monpri == stdprims || tmnew->flags & TM_F_BW) { |
| 55 |
tmnew->monpri = stdprims; |
| 56 |
tmnew->clf[RED] = rgb2xyzmat[1][0]; |
| 57 |
tmnew->clf[GRN] = rgb2xyzmat[1][1]; |
| 58 |
tmnew->clf[BLU] = rgb2xyzmat[1][2]; |
| 59 |
} else { |
| 60 |
comprgb2xyzmat(cmat, tmnew->monpri=monpri); |
| 61 |
tmnew->clf[RED] = cmat[1][0]; |
| 62 |
tmnew->clf[GRN] = cmat[1][1]; |
| 63 |
tmnew->clf[BLU] = cmat[1][2]; |
| 64 |
} |
| 65 |
tmnew->clfb[RED] = 256.*tmnew->clf[RED] + .5; |
| 66 |
tmnew->clfb[GRN] = 256.*tmnew->clf[GRN] + .5; |
| 67 |
tmnew->clfb[BLU] = 256.*tmnew->clf[BLU] + .5; |
| 68 |
tmnew->clfb[EXP] = COLXS; |
| 69 |
/* set gamma value */ |
| 70 |
if (gamval < MINGAM) |
| 71 |
tmnew->mongam = DEFGAM; |
| 72 |
else |
| 73 |
tmnew->mongam = gamval; |
| 74 |
for (i = TM_GAMTSZ; i--; ) |
| 75 |
tmnew->gamb[i] = 256.*pow((i+.5)/TM_GAMTSZ, 1./tmnew->mongam); |
| 76 |
/* set input transform */ |
| 77 |
tmnew->inppri = tmnew->monpri; |
| 78 |
tmnew->cmat[0][0] = tmnew->cmat[1][1] = tmnew->cmat[2][2] = |
| 79 |
tmnew->inpsf = WHTEFFICACY; |
| 80 |
tmnew->inpsfb = TM_BRTSCALE*log(tmnew->inpsf) + .5; |
| 81 |
tmnew->cmat[0][1] = tmnew->cmat[0][2] = tmnew->cmat[1][0] = |
| 82 |
tmnew->cmat[1][2] = tmnew->cmat[2][0] = tmnew->cmat[2][1] = 0.; |
| 83 |
tmnew->flags &= ~TM_F_NEEDMAT; |
| 84 |
tmnew->brmin = tmnew->brmax = 0; |
| 85 |
tmnew->histo = NULL; |
| 86 |
tmnew->lumap = NULL; |
| 87 |
tmnew->tmprev = NULL; |
| 88 |
|
| 89 |
tmnew->flags |= TM_F_INITED; |
| 90 |
/* make it current */ |
| 91 |
tmnew->tmprev = tmTop; |
| 92 |
return(tmTop = tmnew); |
| 93 |
} |
| 94 |
|
| 95 |
|
| 96 |
int |
| 97 |
tmSetSpace(pri, sf) /* set input color space for conversions */ |
| 98 |
RGBPRIMP pri; |
| 99 |
double sf; |
| 100 |
{ |
| 101 |
static char funcName[] = "tmSetSpace"; |
| 102 |
register int i, j; |
| 103 |
/* error check */ |
| 104 |
if (tmTop == NULL) |
| 105 |
returnErr(TM_E_TMINVAL); |
| 106 |
if (sf <= 1e-12) |
| 107 |
returnErr(TM_E_ILLEGAL); |
| 108 |
/* check if no change */ |
| 109 |
if (pri == tmTop->inppri && FEQ(sf, tmTop->inpsf)) |
| 110 |
returnOK; |
| 111 |
tmTop->inppri = pri; /* let's set it */ |
| 112 |
tmTop->inpsf = sf; |
| 113 |
tmTop->inpsfb = TM_BRTSCALE*log(sf) + (sf>=1. ? .5 : -.5); |
| 114 |
|
| 115 |
if (tmTop->flags & TM_F_BW) { /* color doesn't matter */ |
| 116 |
tmTop->monpri = tmTop->inppri; /* eliminate xform */ |
| 117 |
if (tmTop->inppri == TM_XYZPRIM) { |
| 118 |
tmTop->clf[CIEX] = tmTop->clf[CIEZ] = 0.; |
| 119 |
tmTop->clf[CIEY] = 1.; |
| 120 |
tmTop->clfb[CIEX] = tmTop->clfb[CIEZ] = 0; |
| 121 |
tmTop->clfb[CIEY] = 255; |
| 122 |
} else { |
| 123 |
comprgb2xyzmat(tmTop->cmat, tmTop->monpri); |
| 124 |
tmTop->clf[RED] = tmTop->cmat[1][0]; |
| 125 |
tmTop->clf[GRN] = tmTop->cmat[1][1]; |
| 126 |
tmTop->clf[BLU] = tmTop->cmat[1][2]; |
| 127 |
} |
| 128 |
tmTop->cmat[0][0] = tmTop->cmat[1][1] = tmTop->cmat[2][2] = |
| 129 |
tmTop->inpsf; |
| 130 |
tmTop->cmat[0][1] = tmTop->cmat[0][2] = tmTop->cmat[1][0] = |
| 131 |
tmTop->cmat[1][2] = tmTop->cmat[2][0] = tmTop->cmat[2][1] = 0.; |
| 132 |
|
| 133 |
} else if (tmTop->inppri == TM_XYZPRIM) /* input is XYZ */ |
| 134 |
compxyz2rgbmat(tmTop->cmat, tmTop->monpri); |
| 135 |
|
| 136 |
else { /* input is RGB */ |
| 137 |
if (tmTop->inppri != tmTop->monpri && |
| 138 |
PRIMEQ(tmTop->inppri, tmTop->monpri)) |
| 139 |
tmTop->inppri = tmTop->monpri; /* no xform */ |
| 140 |
comprgb2rgbmat(tmTop->cmat, tmTop->inppri, tmTop->monpri); |
| 141 |
} |
| 142 |
for (i = 0; i < 3; i++) |
| 143 |
for (j = 0; j < 3; j++) |
| 144 |
tmTop->cmat[i][j] *= tmTop->inpsf; |
| 145 |
if (tmTop->inppri != tmTop->monpri) |
| 146 |
tmTop->flags |= TM_F_NEEDMAT; |
| 147 |
else |
| 148 |
tmTop->flags &= ~TM_F_NEEDMAT; |
| 149 |
returnOK; |
| 150 |
} |
| 151 |
|
| 152 |
|
| 153 |
void |
| 154 |
tmClearHisto() /* clear current histogram */ |
| 155 |
{ |
| 156 |
if (tmTop == NULL || tmTop->histo == NULL) |
| 157 |
return; |
| 158 |
free((char *)tmTop->histo); |
| 159 |
tmTop->histo = NULL; |
| 160 |
} |
| 161 |
|
| 162 |
|
| 163 |
int |
| 164 |
tmCvColors(ls, cs, scan, len) /* convert float colors */ |
| 165 |
TMbright *ls; |
| 166 |
BYTE *cs; |
| 167 |
COLOR *scan; |
| 168 |
int len; |
| 169 |
{ |
| 170 |
static char funcName[] = "tmCvColors"; |
| 171 |
COLOR cmon; |
| 172 |
double lum, slum; |
| 173 |
register double d; |
| 174 |
register int i; |
| 175 |
|
| 176 |
if (tmTop == NULL) |
| 177 |
returnErr(TM_E_TMINVAL); |
| 178 |
if (ls == NULL | scan == NULL | len <= 0) |
| 179 |
returnErr(TM_E_ILLEGAL); |
| 180 |
for (i = len; i--; ) { |
| 181 |
if (tmTop->flags & TM_F_NEEDMAT) /* get monitor RGB */ |
| 182 |
colortrans(cmon, tmTop->cmat, scan[i]); |
| 183 |
else { |
| 184 |
cmon[RED] = tmTop->inpsf*scan[i][RED]; |
| 185 |
cmon[GRN] = tmTop->inpsf*scan[i][GRN]; |
| 186 |
cmon[BLU] = tmTop->inpsf*scan[i][BLU]; |
| 187 |
} |
| 188 |
/* world luminance */ |
| 189 |
lum = tmTop->clf[RED]*cmon[RED] + |
| 190 |
tmTop->clf[GRN]*cmon[GRN] + |
| 191 |
tmTop->clf[BLU]*cmon[BLU] ; |
| 192 |
/* check range */ |
| 193 |
if (clipgamut(cmon, lum, CGAMUT_LOWER, cblack, cwhite)) |
| 194 |
lum = tmTop->clf[RED]*cmon[RED] + |
| 195 |
tmTop->clf[GRN]*cmon[GRN] + |
| 196 |
tmTop->clf[BLU]*cmon[BLU] ; |
| 197 |
if (lum < MINLUM) { |
| 198 |
ls[i] = MINBRT-1; /* bogus value */ |
| 199 |
lum = MINLUM; |
| 200 |
} else { |
| 201 |
d = TM_BRTSCALE*log(lum); /* encode it */ |
| 202 |
ls[i] = d>0. ? (int)(d+.5) : (int)(d-.5); |
| 203 |
} |
| 204 |
if (cs == TM_NOCHROM) /* no color? */ |
| 205 |
continue; |
| 206 |
if (tmTop->flags & TM_F_MESOPIC && lum < LMESUPPER) { |
| 207 |
slum = scotlum(cmon); /* mesopic adj. */ |
| 208 |
if (lum < LMESLOWER) |
| 209 |
cmon[RED] = cmon[GRN] = cmon[BLU] = slum; |
| 210 |
else { |
| 211 |
d = (lum - LMESLOWER)/(LMESUPPER - LMESLOWER); |
| 212 |
if (tmTop->flags & TM_F_BW) |
| 213 |
cmon[RED] = cmon[GRN] = |
| 214 |
cmon[BLU] = d*lum; |
| 215 |
else |
| 216 |
scalecolor(cmon, d); |
| 217 |
d = (1.-d)*slum; |
| 218 |
cmon[RED] += d; |
| 219 |
cmon[GRN] += d; |
| 220 |
cmon[BLU] += d; |
| 221 |
} |
| 222 |
} else if (tmTop->flags & TM_F_BW) { |
| 223 |
cmon[RED] = cmon[GRN] = cmon[BLU] = lum; |
| 224 |
} |
| 225 |
d = tmTop->clf[RED]*cmon[RED]/lum; |
| 226 |
/* cs[3*i ] = d>.999 ? 255 : 256.*pow(d, 1./tmTop->mongam); */ |
| 227 |
cs[3*i ] = d>.999 ? 255 : tmTop->gamb[(int)(d*TM_GAMTSZ)]; |
| 228 |
d = tmTop->clf[GRN]*cmon[GRN]/lum; |
| 229 |
/* cs[3*i+1] = d>.999 ? 255 : 256.*pow(d, 1./tmTop->mongam); */ |
| 230 |
cs[3*i+1] = d>.999 ? 255 : tmTop->gamb[(int)(d*TM_GAMTSZ)]; |
| 231 |
d = tmTop->clf[BLU]*cmon[BLU]/lum; |
| 232 |
/* cs[3*i+2] = d>.999 ? 255 : 256.*pow(d, 1./tmTop->mongam); */ |
| 233 |
cs[3*i+2] = d>.999 ? 255 : tmTop->gamb[(int)(d*TM_GAMTSZ)]; |
| 234 |
} |
| 235 |
returnOK; |
| 236 |
} |
| 237 |
|
| 238 |
|
| 239 |
int |
| 240 |
tmAddHisto(ls, len, wt) /* add values to histogram */ |
| 241 |
register TMbright *ls; |
| 242 |
int len; |
| 243 |
int wt; |
| 244 |
{ |
| 245 |
static char funcName[] = "tmAddHisto"; |
| 246 |
int sum, oldorig, oldlen, horig, hlen; |
| 247 |
register int i, j; |
| 248 |
|
| 249 |
if (len <= 0) |
| 250 |
returnErr(TM_E_ILLEGAL); |
| 251 |
if (tmTop == NULL) |
| 252 |
returnErr(TM_E_TMINVAL); |
| 253 |
/* first, grow limits */ |
| 254 |
if (tmTop->histo == NULL) { |
| 255 |
for (i = len; i-- && ls[i] < MINBRT; ) |
| 256 |
; |
| 257 |
if (i < 0) |
| 258 |
returnOK; |
| 259 |
tmTop->brmin = tmTop->brmax = ls[i]; |
| 260 |
oldlen = 0; |
| 261 |
} else { |
| 262 |
oldorig = (tmTop->brmin-MINBRT)/HISTEP; |
| 263 |
oldlen = (tmTop->brmax-MINBRT)/HISTEP + 1 - oldorig; |
| 264 |
} |
| 265 |
for (i = len; i--; ) { |
| 266 |
if ((j = ls[i]) < MINBRT) |
| 267 |
continue; |
| 268 |
if (j < tmTop->brmin) |
| 269 |
tmTop->brmin = j; |
| 270 |
else if (j > tmTop->brmax) |
| 271 |
tmTop->brmax = j; |
| 272 |
} |
| 273 |
horig = (tmTop->brmin-MINBRT)/HISTEP; |
| 274 |
hlen = (tmTop->brmax-MINBRT)/HISTEP + 1 - horig; |
| 275 |
if (hlen > oldlen) { /* (re)allocate histogram */ |
| 276 |
register int *newhist = (int *)calloc(hlen, sizeof(int)); |
| 277 |
if (newhist == NULL) |
| 278 |
returnErr(TM_E_NOMEM); |
| 279 |
if (oldlen) { /* copy and free old */ |
| 280 |
for (i = oldlen, j = i+oldorig-horig; i--; ) |
| 281 |
newhist[--j] = tmTop->histo[i]; |
| 282 |
free((char *)tmTop->histo); |
| 283 |
} |
| 284 |
tmTop->histo = newhist; |
| 285 |
if (tmTop->lumap != NULL) { /* invalid tone map */ |
| 286 |
free((char *)tmTop->lumap); |
| 287 |
tmTop->lumap = NULL; |
| 288 |
} |
| 289 |
} |
| 290 |
if (wt == 0) |
| 291 |
returnOK; |
| 292 |
for (i = len; i--; ) /* add in new counts */ |
| 293 |
if (ls[i] >= MINBRT) |
| 294 |
tmTop->histo[ (ls[i]-MINBRT)/HISTEP - horig ] += wt; |
| 295 |
returnOK; |
| 296 |
} |
| 297 |
|
| 298 |
|
| 299 |
static double |
| 300 |
htcontrs(La) /* human threshold contrast sensitivity, dL(La) */ |
| 301 |
double La; |
| 302 |
{ |
| 303 |
double l10La, l10dL; |
| 304 |
/* formula taken from Ferwerda et al. [SG96] */ |
| 305 |
if (La < 1.148e-4) |
| 306 |
return(1.38e-3); |
| 307 |
l10La = log10(La); |
| 308 |
if (l10La < -1.44) /* rod response regime */ |
| 309 |
l10dL = pow(.405*l10La + 1.6, 2.18) - 2.86; |
| 310 |
else if (l10La < -.0184) |
| 311 |
l10dL = l10La - .395; |
| 312 |
else if (l10La < 1.9) /* cone response regime */ |
| 313 |
l10dL = pow(.249*l10La + .65, 2.7) - .72; |
| 314 |
else |
| 315 |
l10dL = l10La - 1.255; |
| 316 |
|
| 317 |
return(exp10(l10dL)); |
| 318 |
} |
| 319 |
|
| 320 |
|
| 321 |
int |
| 322 |
tmComputeMapping(gamval, Lddyn, Ldmax) |
| 323 |
double gamval; |
| 324 |
double Lddyn; |
| 325 |
double Ldmax; |
| 326 |
{ |
| 327 |
static char funcName[] = "tmComputeMapping"; |
| 328 |
int *histo; |
| 329 |
float *cumf; |
| 330 |
int brt0, histlen, histot, threshold, ceiling, trimmings; |
| 331 |
double logLddyn, Ldmin, Ldavg, Lwavg, Tr, Lw, Ld; |
| 332 |
int4 sum; |
| 333 |
register double d; |
| 334 |
register int i, j; |
| 335 |
|
| 336 |
if (tmTop == NULL || tmTop->histo == NULL) |
| 337 |
returnErr(TM_E_TMINVAL); |
| 338 |
/* check arguments */ |
| 339 |
if (Lddyn < MINLDDYN) Lddyn = DEFLDDYN; |
| 340 |
if (Ldmax < MINLDMAX) Ldmax = DEFLDMAX; |
| 341 |
if (gamval < MINGAM) gamval = tmTop->mongam; |
| 342 |
/* compute handy values */ |
| 343 |
Ldmin = Ldmax/Lddyn; |
| 344 |
logLddyn = log(Lddyn); |
| 345 |
Ldavg = sqrt(Ldmax*Ldmin); |
| 346 |
i = (tmTop->brmin-MINBRT)/HISTEP; |
| 347 |
brt0 = MINBRT + HISTEP/2 + i*HISTEP; |
| 348 |
histlen = (tmTop->brmax-MINBRT)/HISTEP + 1 - i; |
| 349 |
/* allocate temporary tables */ |
| 350 |
histo = (int *)malloc(histlen*sizeof(int)); |
| 351 |
cumf = (float *)malloc((histlen+1)*sizeof(float)); |
| 352 |
if (histo == NULL | cumf == NULL) |
| 353 |
returnErr(TM_E_NOMEM); |
| 354 |
/* histogram total and mean */ |
| 355 |
histot = 0; sum = 0; |
| 356 |
j = brt0 + histlen*HISTEP; |
| 357 |
for (i = histlen; i--; ) { |
| 358 |
histot += (histo[i] = tmTop->histo[i]); |
| 359 |
sum += (j -= HISTEP) * histo[i]; |
| 360 |
} |
| 361 |
threshold = histot*.025 + .5; |
| 362 |
if (threshold < 4) |
| 363 |
returnErr(TM_E_TMFAIL); |
| 364 |
Lwavg = tmLuminance( (double)sum / histot ); |
| 365 |
do { /* iterate to solution */ |
| 366 |
sum = 0; /* compute cumulative probability */ |
| 367 |
for (i = 0; i < histlen; i++) { |
| 368 |
cumf[i] = (double)sum/histot; |
| 369 |
sum += histo[i]; |
| 370 |
} |
| 371 |
cumf[i] = 1.; |
| 372 |
Tr = histot * (double)(tmTop->brmax - tmTop->brmin) / |
| 373 |
((double)histlen*TM_BRTSCALE) / logLddyn; |
| 374 |
ceiling = Tr + 1.; |
| 375 |
trimmings = 0; /* clip to envelope */ |
| 376 |
for (i = histlen; i--; ) { |
| 377 |
if (tmTop->flags & TM_F_HCONTR) { |
| 378 |
Lw = tmLuminance(brt0 + i*HISTEP); |
| 379 |
Ld = Ldmin * exp( logLddyn * |
| 380 |
.5*(cumf[i]+cumf[i+1]) ); |
| 381 |
ceiling = Tr * (htcontrs(Ld) * Lw) / |
| 382 |
(htcontrs(Lw) * Ld) + 1.; |
| 383 |
} |
| 384 |
if (histo[i] > ceiling) { |
| 385 |
trimmings += histo[i] - ceiling; |
| 386 |
histo[i] = ceiling; |
| 387 |
} |
| 388 |
} |
| 389 |
} while ((histot -= trimmings) > threshold && trimmings > threshold); |
| 390 |
|
| 391 |
if (tmTop->lumap == NULL) { /* allocate luminance map */ |
| 392 |
tmTop->lumap = (unsigned short *)malloc( |
| 393 |
(tmTop->brmax-tmTop->brmin+1)*sizeof(unsigned short) ); |
| 394 |
if (tmTop->lumap == NULL) |
| 395 |
returnErr(TM_E_NOMEM); |
| 396 |
} |
| 397 |
if (tmTop->flags & TM_F_LINEAR || histot <= threshold) { |
| 398 |
/* linear tone mapping */ |
| 399 |
if (tmTop->flags & TM_F_HCONTR) |
| 400 |
d = htcontrs(Ldavg) / htcontrs(Lwavg); |
| 401 |
else |
| 402 |
d = Ldavg / Lwavg; |
| 403 |
d = log(d/Ldmax); |
| 404 |
for (i = tmTop->brmax-tmTop->brmin+1; i--; ) |
| 405 |
tmTop->lumap[i] = 256. * exp( |
| 406 |
( d + (tmTop->brmin+i)/(double)TM_BRTSCALE ) |
| 407 |
/ gamval ); |
| 408 |
} else { |
| 409 |
/* histogram adjustment */ |
| 410 |
for (i = tmTop->brmax-tmTop->brmin+1; i--; ) { |
| 411 |
j = d = (double)i/(tmTop->brmax-tmTop->brmin)*histlen; |
| 412 |
d -= (double)j; |
| 413 |
Ld = Ldmin*exp(logLddyn*((1.-d)*cumf[j]+d*cumf[j+1])); |
| 414 |
d = (Ld - Ldmin)/(Ldmax - Ldmin); |
| 415 |
tmTop->lumap[i] = 256.*pow(d, 1./gamval); |
| 416 |
} |
| 417 |
} |
| 418 |
free((char *)histo); |
| 419 |
free((char *)cumf); |
| 420 |
returnOK; |
| 421 |
} |
| 422 |
|
| 423 |
|
| 424 |
int |
| 425 |
tmMapPixels(ps, ls, cs, len) |
| 426 |
register BYTE *ps; |
| 427 |
TMbright *ls; |
| 428 |
register BYTE *cs; |
| 429 |
int len; |
| 430 |
{ |
| 431 |
static char funcName[] = "tmMapPixels"; |
| 432 |
int rdiv, gdiv, bdiv; |
| 433 |
register int li, pv; |
| 434 |
|
| 435 |
if (tmTop == NULL || tmTop->lumap == NULL) |
| 436 |
returnErr(TM_E_TMINVAL); |
| 437 |
if (ps == NULL | ls == NULL | len <= 0) |
| 438 |
returnErr(TM_E_ILLEGAL); |
| 439 |
rdiv = tmTop->gamb[((int4)TM_GAMTSZ*tmTop->clfb[RED])>>8]; |
| 440 |
gdiv = tmTop->gamb[((int4)TM_GAMTSZ*tmTop->clfb[GRN])>>8]; |
| 441 |
bdiv = tmTop->gamb[((int4)TM_GAMTSZ*tmTop->clfb[BLU])>>8]; |
| 442 |
while (len--) { |
| 443 |
if ((li = *ls++) < tmTop->brmin) |
| 444 |
li = tmTop->brmin; |
| 445 |
else if (li > tmTop->brmax) |
| 446 |
li = tmTop->brmax; |
| 447 |
li = tmTop->lumap[li - tmTop->brmin]; |
| 448 |
if (cs == TM_NOCHROM) |
| 449 |
*ps++ = li>255 ? 255 : li; |
| 450 |
else { |
| 451 |
pv = *cs++ * li / rdiv; |
| 452 |
*ps++ = pv>255 ? 255 : pv; |
| 453 |
pv = *cs++ * li / gdiv; |
| 454 |
*ps++ = pv>255 ? 255 : pv; |
| 455 |
pv = *cs++ * li / bdiv; |
| 456 |
*ps++ = pv>255 ? 255 : pv; |
| 457 |
} |
| 458 |
} |
| 459 |
returnOK; |
| 460 |
} |
| 461 |
|
| 462 |
|
| 463 |
struct tmStruct * |
| 464 |
tmPop() /* pop top tone mapping off stack */ |
| 465 |
{ |
| 466 |
register struct tmStruct *tms; |
| 467 |
|
| 468 |
if ((tms = tmTop) != NULL) |
| 469 |
tmTop = tms->tmprev; |
| 470 |
return(tms); |
| 471 |
} |
| 472 |
|
| 473 |
|
| 474 |
int |
| 475 |
tmPull(tms) /* pull a tone mapping from stack */ |
| 476 |
register struct tmStruct *tms; |
| 477 |
{ |
| 478 |
register struct tmStruct *tms2; |
| 479 |
/* special cases first */ |
| 480 |
if (tms == NULL | tmTop == NULL) |
| 481 |
return(0); |
| 482 |
if (tms == tmTop) { |
| 483 |
tmTop = tms->tmprev; |
| 484 |
tms->tmprev = NULL; |
| 485 |
return(1); |
| 486 |
} |
| 487 |
for (tms2 = tmTop; tms2->tmprev != NULL; tms2 = tms2->tmprev) |
| 488 |
if (tms == tms2->tmprev) { /* remove it */ |
| 489 |
tms2->tmprev = tms->tmprev; |
| 490 |
tms->tmprev = NULL; |
| 491 |
return(1); |
| 492 |
} |
| 493 |
return(0); /* not found on stack */ |
| 494 |
} |
| 495 |
|
| 496 |
|
| 497 |
int |
| 498 |
tmPush(tms) /* push tone mapping on top of stack */ |
| 499 |
register struct tmStruct *tms; |
| 500 |
{ |
| 501 |
static char funcName[] = "tmPush"; |
| 502 |
/* check validity */ |
| 503 |
if (tms == NULL || !(tms->flags & TM_F_INITED)) |
| 504 |
returnErr(TM_E_ILLEGAL); |
| 505 |
if (tms == tmTop) /* check necessity */ |
| 506 |
returnOK; |
| 507 |
/* pull if already in stack */ |
| 508 |
(void)tmPull(tms); |
| 509 |
/* push it on top */ |
| 510 |
tms->tmprev = tmTop; |
| 511 |
tmTop = tms; |
| 512 |
returnOK; |
| 513 |
} |
| 514 |
|
| 515 |
|
| 516 |
void |
| 517 |
tmDone(tms) /* done with tone mapping -- destroy it */ |
| 518 |
register struct tmStruct *tms; |
| 519 |
{ |
| 520 |
/* NULL arg. is equiv. to tmTop */ |
| 521 |
if (tms == NULL && (tms = tmTop) == NULL) |
| 522 |
return; |
| 523 |
/* take out of stack if present */ |
| 524 |
(void)tmPull(tms); |
| 525 |
/* free tables */ |
| 526 |
if (tms->histo != NULL) |
| 527 |
free((char *)tms->histo); |
| 528 |
if (tms->lumap != NULL) |
| 529 |
free((char *)tms->lumap); |
| 530 |
tms->flags = 0; |
| 531 |
free((char *)tms); /* free basic structure */ |
| 532 |
} |
