| 1 |
#ifndef lint |
| 2 |
static const char RCSid[] = "$Id: tonemap.c,v 3.22 2006/03/23 22:01:43 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 |
/* luminance->brightness lookup */ |
| 26 |
static TMbright *tmFloat2BrtLUT; |
| 27 |
|
| 28 |
#define tmCvLumLUfp(pf) tmFloat2BrtLUT[*(int32 *)(pf) >> 15] |
| 29 |
|
| 30 |
|
| 31 |
TMstruct * |
| 32 |
tmInit( /* initialize new tone mapping */ |
| 33 |
int flags, |
| 34 |
RGBPRIMP monpri, |
| 35 |
double gamval |
| 36 |
) |
| 37 |
{ |
| 38 |
COLORMAT cmat; |
| 39 |
TMstruct *tmnew; |
| 40 |
int i; |
| 41 |
/* allocate structure */ |
| 42 |
tmnew = (TMstruct *)malloc(sizeof(TMstruct)); |
| 43 |
if (tmnew == NULL) |
| 44 |
return(NULL); |
| 45 |
|
| 46 |
tmnew->flags = flags & ~TM_F_UNIMPL; |
| 47 |
if (tmnew->flags & TM_F_BW) |
| 48 |
tmnew->flags &= ~TM_F_MESOPIC; |
| 49 |
/* set monitor transform */ |
| 50 |
if (monpri == NULL || monpri == stdprims || tmnew->flags & TM_F_BW) { |
| 51 |
tmnew->monpri = stdprims; |
| 52 |
tmnew->clf[RED] = rgb2xyzmat[1][0]; |
| 53 |
tmnew->clf[GRN] = rgb2xyzmat[1][1]; |
| 54 |
tmnew->clf[BLU] = rgb2xyzmat[1][2]; |
| 55 |
} else { |
| 56 |
comprgb2xyzWBmat(cmat, tmnew->monpri=monpri); |
| 57 |
tmnew->clf[RED] = cmat[1][0]; |
| 58 |
tmnew->clf[GRN] = cmat[1][1]; |
| 59 |
tmnew->clf[BLU] = cmat[1][2]; |
| 60 |
} |
| 61 |
/* set gamma value */ |
| 62 |
if (gamval < MINGAM) |
| 63 |
tmnew->mongam = DEFGAM; |
| 64 |
else |
| 65 |
tmnew->mongam = gamval; |
| 66 |
/* set color divisors */ |
| 67 |
for (i = 0; i < 3; i++) |
| 68 |
tmnew->cdiv[i] = 256.*pow(tmnew->clf[i], 1./tmnew->mongam); |
| 69 |
|
| 70 |
/* set input transform */ |
| 71 |
tmnew->inppri = tmnew->monpri; |
| 72 |
tmnew->cmat[0][0] = tmnew->cmat[1][1] = tmnew->cmat[2][2] = |
| 73 |
tmnew->inpsf = WHTEFFICACY; |
| 74 |
tmnew->cmat[0][1] = tmnew->cmat[0][2] = tmnew->cmat[1][0] = |
| 75 |
tmnew->cmat[1][2] = tmnew->cmat[2][0] = tmnew->cmat[2][1] = 0.; |
| 76 |
tmnew->inpdat = NULL; |
| 77 |
tmnew->hbrmin = 10; tmnew->hbrmax = -10; |
| 78 |
tmnew->histo = NULL; |
| 79 |
tmnew->mbrmin = 10; tmnew->mbrmax = -10; |
| 80 |
tmnew->lumap = NULL; |
| 81 |
/* zero private data */ |
| 82 |
for (i = TM_MAXPKG; i--; ) |
| 83 |
tmnew->pd[i] = NULL; |
| 84 |
tmnew->lastError = TM_E_OK; |
| 85 |
tmnew->lastFunc = "NoErr"; |
| 86 |
/* return new TMstruct */ |
| 87 |
return(tmnew); |
| 88 |
} |
| 89 |
|
| 90 |
|
| 91 |
int |
| 92 |
tmSetSpace( /* set input color space for conversions */ |
| 93 |
TMstruct *tms, |
| 94 |
RGBPRIMP pri, |
| 95 |
double sf, |
| 96 |
MEM_PTR dat |
| 97 |
) |
| 98 |
{ |
| 99 |
static const char funcName[] = "tmSetSpace"; |
| 100 |
int i, j; |
| 101 |
/* error check */ |
| 102 |
if (tms == NULL) |
| 103 |
returnErr(TM_E_TMINVAL); |
| 104 |
if (sf <= 1e-12) |
| 105 |
returnErr(TM_E_ILLEGAL); |
| 106 |
/* check if no change */ |
| 107 |
if (pri == tms->inppri && FEQ(sf, tms->inpsf) && dat == tms->inpdat) |
| 108 |
returnOK; |
| 109 |
tms->inppri = pri; /* let's set it */ |
| 110 |
tms->inpsf = sf; |
| 111 |
tms->inpdat = dat; |
| 112 |
|
| 113 |
if (tms->flags & TM_F_BW) { /* color doesn't matter */ |
| 114 |
tms->monpri = tms->inppri; /* eliminate xform */ |
| 115 |
if (tms->inppri == TM_XYZPRIM) { |
| 116 |
tms->clf[CIEX] = tms->clf[CIEZ] = 0.; |
| 117 |
tms->clf[CIEY] = 1.; |
| 118 |
} else { |
| 119 |
comprgb2xyzWBmat(tms->cmat, tms->monpri); |
| 120 |
tms->clf[RED] = tms->cmat[1][0]; |
| 121 |
tms->clf[GRN] = tms->cmat[1][1]; |
| 122 |
tms->clf[BLU] = tms->cmat[1][2]; |
| 123 |
} |
| 124 |
tms->cmat[0][0] = tms->cmat[1][1] = tms->cmat[2][2] = |
| 125 |
tms->inpsf; |
| 126 |
tms->cmat[0][1] = tms->cmat[0][2] = tms->cmat[1][0] = |
| 127 |
tms->cmat[1][2] = tms->cmat[2][0] = tms->cmat[2][1] = 0.; |
| 128 |
|
| 129 |
} else if (tms->inppri == TM_XYZPRIM) /* input is XYZ */ |
| 130 |
compxyz2rgbWBmat(tms->cmat, tms->monpri); |
| 131 |
|
| 132 |
else { /* input is RGB */ |
| 133 |
if (tms->inppri != tms->monpri && |
| 134 |
PRIMEQ(tms->inppri, tms->monpri)) |
| 135 |
tms->inppri = tms->monpri; /* no xform */ |
| 136 |
comprgb2rgbWBmat(tms->cmat, tms->inppri, tms->monpri); |
| 137 |
} |
| 138 |
for (i = 0; i < 3; i++) |
| 139 |
for (j = 0; j < 3; j++) |
| 140 |
tms->cmat[i][j] *= tms->inpsf; |
| 141 |
/* set color divisors */ |
| 142 |
for (i = 0; i < 3; i++) |
| 143 |
if (tms->clf[i] > .001) |
| 144 |
tms->cdiv[i] = |
| 145 |
256.*pow(tms->clf[i], 1./tms->mongam); |
| 146 |
else |
| 147 |
tms->cdiv[i] = 1; |
| 148 |
/* notify packages */ |
| 149 |
for (i = tmNumPkgs; i--; ) |
| 150 |
if (tms->pd[i] != NULL && tmPkg[i]->NewSpace != NULL) |
| 151 |
(*tmPkg[i]->NewSpace)(tms); |
| 152 |
returnOK; |
| 153 |
} |
| 154 |
|
| 155 |
|
| 156 |
void |
| 157 |
tmClearHisto( /* clear current histogram */ |
| 158 |
TMstruct *tms |
| 159 |
) |
| 160 |
{ |
| 161 |
if (tms == NULL || tms->histo == NULL) |
| 162 |
return; |
| 163 |
free((MEM_PTR)tms->histo); |
| 164 |
tms->histo = NULL; |
| 165 |
} |
| 166 |
|
| 167 |
|
| 168 |
TMbright |
| 169 |
tmCvLuminance( /* convert a single luminance */ |
| 170 |
double lum |
| 171 |
) |
| 172 |
{ |
| 173 |
double d; |
| 174 |
|
| 175 |
#ifdef isfinite |
| 176 |
if (!isfinite(lum) || lum <= TM_NOLUM) |
| 177 |
#else |
| 178 |
if (lum <= TM_NOLUM) |
| 179 |
#endif |
| 180 |
return(TM_NOBRT); |
| 181 |
d = TM_BRTSCALE*log(lum); |
| 182 |
if (d > 0.) |
| 183 |
return((TMbright)(d+.5)); |
| 184 |
return((TMbright)(d-.5)); |
| 185 |
} |
| 186 |
|
| 187 |
|
| 188 |
int |
| 189 |
tmCvLums( /* convert luminances using lookup */ |
| 190 |
TMbright *ls, |
| 191 |
float *scan, |
| 192 |
int len |
| 193 |
) |
| 194 |
{ |
| 195 |
if (tmFloat2BrtLUT == NULL) { /* initialize lookup table */ |
| 196 |
int32 i; |
| 197 |
tmFloat2BrtLUT = (TMbright *)malloc(sizeof(TMbright)*0x10000); |
| 198 |
if (tmFloat2BrtLUT == NULL) |
| 199 |
return(TM_E_NOMEM); |
| 200 |
for (i = 0; i < 0x10000; i++) { |
| 201 |
int32 l = (i<<1 | 1) << 14; |
| 202 |
#ifndef isfinite |
| 203 |
if ((l & 0x7f800000) == 0x7f800000) |
| 204 |
tmFloat2BrtLUT[i] = TM_NOBRT; |
| 205 |
else |
| 206 |
#endif |
| 207 |
tmFloat2BrtLUT[i] = tmCvLuminance(*(float *)&l); |
| 208 |
} |
| 209 |
} |
| 210 |
if (len <= 0) |
| 211 |
return(TM_E_OK); |
| 212 |
if ((ls == NULL) | (scan == NULL)) |
| 213 |
return(TM_E_ILLEGAL); |
| 214 |
while (len--) { |
| 215 |
if (*scan <= TM_NOLUM) { |
| 216 |
*ls++ = TM_NOBRT; |
| 217 |
++scan; |
| 218 |
continue; |
| 219 |
} |
| 220 |
*ls++ = tmCvLumLUfp(scan++); |
| 221 |
} |
| 222 |
return(TM_E_OK); |
| 223 |
} |
| 224 |
|
| 225 |
|
| 226 |
int |
| 227 |
tmCvGrays( /* convert float gray values */ |
| 228 |
TMstruct *tms, |
| 229 |
TMbright *ls, |
| 230 |
float *scan, |
| 231 |
int len |
| 232 |
) |
| 233 |
{ |
| 234 |
static const char funcName[] = "tmCvGrays"; |
| 235 |
double d; |
| 236 |
int i; |
| 237 |
|
| 238 |
if (tms == NULL) |
| 239 |
returnErr(TM_E_TMINVAL); |
| 240 |
if ((ls == NULL) | (scan == NULL) | (len < 0)) |
| 241 |
returnErr(TM_E_ILLEGAL); |
| 242 |
for (i = len; i--; ) { |
| 243 |
float lum = tms->inpsf * scan[i]; |
| 244 |
if (lum <= TM_NOLUM) |
| 245 |
ls[i] = TM_NOBRT; |
| 246 |
else |
| 247 |
ls[i] = tmCvLumLUfp(&lum); |
| 248 |
} |
| 249 |
returnOK; |
| 250 |
} |
| 251 |
|
| 252 |
|
| 253 |
int |
| 254 |
tmCvColors( /* convert float colors */ |
| 255 |
TMstruct *tms, |
| 256 |
TMbright *ls, |
| 257 |
BYTE *cs, |
| 258 |
COLOR *scan, |
| 259 |
int len |
| 260 |
) |
| 261 |
{ |
| 262 |
static const char funcName[] = "tmCvColors"; |
| 263 |
static COLOR csmall = {.5*MINLUM, .5*MINLUM, .5*MINLUM}; |
| 264 |
static BYTE gamtab[1024]; |
| 265 |
static double curgam = .0; |
| 266 |
COLOR cmon; |
| 267 |
float lum, slum, d; |
| 268 |
int i; |
| 269 |
|
| 270 |
if (tms == NULL) |
| 271 |
returnErr(TM_E_TMINVAL); |
| 272 |
if ((ls == NULL) | (scan == NULL) | (len < 0)) |
| 273 |
returnErr(TM_E_ILLEGAL); |
| 274 |
tmCvLums(NULL, NULL, 0); /* initialize */ |
| 275 |
if (cs != TM_NOCHROM && fabs(tms->mongam - curgam) > .02) { |
| 276 |
curgam = tms->mongam; /* (re)build table */ |
| 277 |
for (i = 1024; i--; ) |
| 278 |
gamtab[i] = (int)(256.*pow((i+.5)/1024., 1./curgam)); |
| 279 |
} |
| 280 |
for (i = len; i--; ) { |
| 281 |
if (tmNeedMatrix(tms)) { /* get monitor RGB */ |
| 282 |
colortrans(cmon, tms->cmat, scan[i]); |
| 283 |
} else { |
| 284 |
cmon[RED] = tms->inpsf*scan[i][RED]; |
| 285 |
cmon[GRN] = tms->inpsf*scan[i][GRN]; |
| 286 |
cmon[BLU] = tms->inpsf*scan[i][BLU]; |
| 287 |
} |
| 288 |
#ifdef isfinite |
| 289 |
if (!isfinite(cmon[RED]) || cmon[RED] < .0f) cmon[RED] = .0f; |
| 290 |
if (!isfinite(cmon[GRN]) || cmon[GRN] < .0f) cmon[GRN] = .0f; |
| 291 |
if (!isfinite(cmon[BLU]) || cmon[BLU] < .0f) cmon[BLU] = .0f; |
| 292 |
#else |
| 293 |
if (cmon[RED] < .0f) cmon[RED] = .0f; |
| 294 |
if (cmon[GRN] < .0f) cmon[GRN] = .0f; |
| 295 |
if (cmon[BLU] < .0f) cmon[BLU] = .0f; |
| 296 |
#endif |
| 297 |
/* world luminance */ |
| 298 |
lum = tms->clf[RED]*cmon[RED] + |
| 299 |
tms->clf[GRN]*cmon[GRN] + |
| 300 |
tms->clf[BLU]*cmon[BLU] ; |
| 301 |
if (lum <= TM_NOLUM) /* convert brightness */ |
| 302 |
ls[i] = TM_NOBRT; |
| 303 |
else |
| 304 |
ls[i] = tmCvLumLUfp(&lum); |
| 305 |
if (cs == TM_NOCHROM) /* no color? */ |
| 306 |
continue; |
| 307 |
if (tms->flags & TM_F_MESOPIC && lum < LMESUPPER) { |
| 308 |
slum = scotlum(cmon); /* mesopic adj. */ |
| 309 |
if (lum < LMESLOWER) |
| 310 |
cmon[RED] = cmon[GRN] = cmon[BLU] = slum; |
| 311 |
else { |
| 312 |
d = (lum - LMESLOWER)/(LMESUPPER - LMESLOWER); |
| 313 |
if (tms->flags & TM_F_BW) |
| 314 |
cmon[RED] = cmon[GRN] = |
| 315 |
cmon[BLU] = d*lum; |
| 316 |
else |
| 317 |
scalecolor(cmon, d); |
| 318 |
d = (1.f-d)*slum; |
| 319 |
cmon[RED] += d; |
| 320 |
cmon[GRN] += d; |
| 321 |
cmon[BLU] += d; |
| 322 |
} |
| 323 |
} else if (tms->flags & TM_F_BW) { |
| 324 |
cmon[RED] = cmon[GRN] = cmon[BLU] = lum; |
| 325 |
} |
| 326 |
d = tms->clf[RED]*cmon[RED]/lum; |
| 327 |
cs[3*i ] = d>=.999f ? 255 : gamtab[(int)(1024.f*d)]; |
| 328 |
d = tms->clf[GRN]*cmon[GRN]/lum; |
| 329 |
cs[3*i+1] = d>=.999f ? 255 : gamtab[(int)(1024.f*d)]; |
| 330 |
d = tms->clf[BLU]*cmon[BLU]/lum; |
| 331 |
cs[3*i+2] = d>=.999f ? 255 : gamtab[(int)(1024.f*d)]; |
| 332 |
} |
| 333 |
returnOK; |
| 334 |
} |
| 335 |
|
| 336 |
|
| 337 |
int |
| 338 |
tmAddHisto( /* add values to histogram */ |
| 339 |
TMstruct *tms, |
| 340 |
TMbright *ls, |
| 341 |
int len, |
| 342 |
int wt |
| 343 |
) |
| 344 |
{ |
| 345 |
static const char funcName[] = "tmAddHisto"; |
| 346 |
int oldorig=0, oldlen, horig, hlen; |
| 347 |
int i, j; |
| 348 |
|
| 349 |
if (tms == NULL) |
| 350 |
returnErr(TM_E_TMINVAL); |
| 351 |
if (len < 0) |
| 352 |
returnErr(TM_E_ILLEGAL); |
| 353 |
if (len == 0) |
| 354 |
returnOK; |
| 355 |
/* first, grow limits */ |
| 356 |
if (tms->histo == NULL) { |
| 357 |
for (i = len; i-- && ls[i] < MINBRT; ) |
| 358 |
; |
| 359 |
if (i < 0) |
| 360 |
returnOK; |
| 361 |
tms->hbrmin = tms->hbrmax = ls[i]; |
| 362 |
oldlen = 0; |
| 363 |
} else { |
| 364 |
oldorig = (tms->hbrmin-MINBRT)/HISTEP; |
| 365 |
oldlen = (tms->hbrmax-MINBRT)/HISTEP + 1 - oldorig; |
| 366 |
} |
| 367 |
for (i = len; i--; ) { |
| 368 |
if ((j = ls[i]) < MINBRT) |
| 369 |
continue; |
| 370 |
if (j < tms->hbrmin) |
| 371 |
tms->hbrmin = j; |
| 372 |
else if (j > tms->hbrmax) |
| 373 |
tms->hbrmax = j; |
| 374 |
} |
| 375 |
horig = (tms->hbrmin-MINBRT)/HISTEP; |
| 376 |
hlen = (tms->hbrmax-MINBRT)/HISTEP + 1 - horig; |
| 377 |
if (hlen > oldlen) { /* (re)allocate histogram */ |
| 378 |
int *newhist = (int *)calloc(hlen, sizeof(int)); |
| 379 |
if (newhist == NULL) |
| 380 |
returnErr(TM_E_NOMEM); |
| 381 |
if (oldlen) { /* copy and free old */ |
| 382 |
for (i = oldlen, j = i+oldorig-horig; i; ) |
| 383 |
newhist[--j] = tms->histo[--i]; |
| 384 |
free((MEM_PTR)tms->histo); |
| 385 |
} |
| 386 |
tms->histo = newhist; |
| 387 |
} |
| 388 |
if (wt == 0) |
| 389 |
returnOK; |
| 390 |
for (i = len; i--; ) /* add in new counts */ |
| 391 |
if (ls[i] >= MINBRT) |
| 392 |
tms->histo[ (ls[i]-MINBRT)/HISTEP - horig ] += wt; |
| 393 |
returnOK; |
| 394 |
} |
| 395 |
|
| 396 |
|
| 397 |
static double |
| 398 |
htcontrs( /* human threshold contrast sensitivity, dL(La) */ |
| 399 |
double La |
| 400 |
) |
| 401 |
{ |
| 402 |
double l10La, l10dL; |
| 403 |
/* formula taken from Ferwerda et al. [SG96] */ |
| 404 |
if (La < 1.148e-4) |
| 405 |
return(1.38e-3); |
| 406 |
l10La = log10(La); |
| 407 |
if (l10La < -1.44) /* rod response regime */ |
| 408 |
l10dL = pow(.405*l10La + 1.6, 2.18) - 2.86; |
| 409 |
else if (l10La < -.0184) |
| 410 |
l10dL = l10La - .395; |
| 411 |
else if (l10La < 1.9) /* cone response regime */ |
| 412 |
l10dL = pow(.249*l10La + .65, 2.7) - .72; |
| 413 |
else |
| 414 |
l10dL = l10La - 1.255; |
| 415 |
|
| 416 |
return(exp10(l10dL)); |
| 417 |
} |
| 418 |
|
| 419 |
|
| 420 |
static int |
| 421 |
tmNewMap( /* allocate new tone-mapping array */ |
| 422 |
TMstruct *tms |
| 423 |
) |
| 424 |
{ |
| 425 |
if (tms->lumap != NULL && (tms->mbrmax - tms->mbrmin) != |
| 426 |
(tms->hbrmax - tms->hbrmin)) { |
| 427 |
free((MEM_PTR)tms->lumap); |
| 428 |
tms->lumap = NULL; |
| 429 |
} |
| 430 |
tms->mbrmin = tms->hbrmin; |
| 431 |
tms->mbrmax = tms->hbrmax; |
| 432 |
if (tms->mbrmin > tms->mbrmax) |
| 433 |
return 0; |
| 434 |
if (tms->lumap == NULL) |
| 435 |
tms->lumap = (unsigned short *)malloc(sizeof(unsigned short)* |
| 436 |
(tms->mbrmax-tms->mbrmin+1)); |
| 437 |
return(tms->lumap != NULL); |
| 438 |
} |
| 439 |
|
| 440 |
|
| 441 |
int |
| 442 |
tmFixedMapping( /* compute fixed, linear tone-mapping */ |
| 443 |
TMstruct *tms, |
| 444 |
double expmult, |
| 445 |
double gamval |
| 446 |
) |
| 447 |
{ |
| 448 |
static const char funcName[] = "tmFixedMapping"; |
| 449 |
double d; |
| 450 |
int i; |
| 451 |
|
| 452 |
if (!tmNewMap(tms)) |
| 453 |
returnErr(TM_E_NOMEM); |
| 454 |
if (expmult <= .0) |
| 455 |
expmult = 1.; |
| 456 |
if (gamval < MINGAM) |
| 457 |
gamval = tms->mongam; |
| 458 |
d = log(expmult/tms->inpsf); |
| 459 |
for (i = tms->mbrmax-tms->mbrmin+1; i--; ) |
| 460 |
tms->lumap[i] = 256. * exp( |
| 461 |
( d + (tms->mbrmin+i)*(1./TM_BRTSCALE) ) |
| 462 |
/ gamval ); |
| 463 |
returnOK; |
| 464 |
} |
| 465 |
|
| 466 |
|
| 467 |
int |
| 468 |
tmComputeMapping( /* compute histogram tone-mapping */ |
| 469 |
TMstruct *tms, |
| 470 |
double gamval, |
| 471 |
double Lddyn, |
| 472 |
double Ldmax |
| 473 |
) |
| 474 |
{ |
| 475 |
static const char funcName[] = "tmComputeMapping"; |
| 476 |
int *histo; |
| 477 |
float *cumf; |
| 478 |
int brt0, histlen, threshold, ceiling, trimmings; |
| 479 |
double logLddyn, Ldmin, Ldavg, Lwavg, Tr, Lw, Ld; |
| 480 |
int32 histot; |
| 481 |
double sum; |
| 482 |
double d; |
| 483 |
int i, j; |
| 484 |
|
| 485 |
if (tms == NULL || tms->histo == NULL) |
| 486 |
returnErr(TM_E_TMINVAL); |
| 487 |
/* check arguments */ |
| 488 |
if (Lddyn < MINLDDYN) Lddyn = DEFLDDYN; |
| 489 |
if (Ldmax < MINLDMAX) Ldmax = DEFLDMAX; |
| 490 |
if (gamval < MINGAM) gamval = tms->mongam; |
| 491 |
/* compute handy values */ |
| 492 |
Ldmin = Ldmax/Lddyn; |
| 493 |
logLddyn = log(Lddyn); |
| 494 |
Ldavg = sqrt(Ldmax*Ldmin); |
| 495 |
i = (tms->hbrmin-MINBRT)/HISTEP; |
| 496 |
brt0 = MINBRT + HISTEP/2 + i*HISTEP; |
| 497 |
histlen = (tms->hbrmax-MINBRT)/HISTEP + 1 - i; |
| 498 |
/* histogram total and mean */ |
| 499 |
histot = 0; sum = 0; |
| 500 |
j = brt0 + histlen*HISTEP; |
| 501 |
for (i = histlen; i--; ) { |
| 502 |
histot += tms->histo[i]; |
| 503 |
sum += (j -= HISTEP) * tms->histo[i]; |
| 504 |
} |
| 505 |
threshold = histot*0.005 + .5; |
| 506 |
if (threshold < 4) |
| 507 |
returnErr(TM_E_TMFAIL); |
| 508 |
Lwavg = tmLuminance( (double)sum / histot ); |
| 509 |
/* allocate space for mapping */ |
| 510 |
if (!tmNewMap(tms)) |
| 511 |
returnErr(TM_E_NOMEM); |
| 512 |
/* use linear tone mapping? */ |
| 513 |
if (tms->flags & TM_F_LINEAR) |
| 514 |
goto linearmap; |
| 515 |
/* clamp histogram */ |
| 516 |
histo = (int *)malloc(histlen*sizeof(int)); |
| 517 |
cumf = (float *)malloc((histlen+2)*sizeof(float)); |
| 518 |
if ((histo == NULL) | (cumf == NULL)) |
| 519 |
returnErr(TM_E_NOMEM); |
| 520 |
cumf[histlen+1] = 1.; /* guard for assignment code */ |
| 521 |
for (i = histlen; i--; ) /* make malleable copy */ |
| 522 |
histo[i] = tms->histo[i]; |
| 523 |
do { /* iterate to solution */ |
| 524 |
sum = 0; /* cumulative probability */ |
| 525 |
for (i = 0; i < histlen; i++) { |
| 526 |
cumf[i] = (double)sum/histot; |
| 527 |
sum += histo[i]; |
| 528 |
} |
| 529 |
cumf[histlen] = 1.; |
| 530 |
Tr = histot * (double)(tms->hbrmax - tms->hbrmin) / |
| 531 |
((double)histlen*TM_BRTSCALE) / logLddyn; |
| 532 |
ceiling = Tr + 1.; |
| 533 |
trimmings = 0; /* clip to envelope */ |
| 534 |
for (i = histlen; i--; ) { |
| 535 |
if (tms->flags & TM_F_HCONTR) { |
| 536 |
Lw = tmLuminance(brt0 + i*HISTEP); |
| 537 |
Ld = Ldmin * exp( logLddyn * |
| 538 |
.5*(cumf[i]+cumf[i+1]) ); |
| 539 |
ceiling = Tr * (htcontrs(Ld) * Lw) / |
| 540 |
(htcontrs(Lw) * Ld) + 1.; |
| 541 |
} |
| 542 |
if (histo[i] > ceiling) { |
| 543 |
trimmings += histo[i] - ceiling; |
| 544 |
histo[i] = ceiling; |
| 545 |
} |
| 546 |
} |
| 547 |
/* check if we're out of data */ |
| 548 |
if ((histot -= trimmings) <= threshold) { |
| 549 |
free((MEM_PTR)histo); |
| 550 |
free((MEM_PTR)cumf); |
| 551 |
goto linearmap; |
| 552 |
} |
| 553 |
} while (trimmings > threshold); |
| 554 |
/* assign tone-mapping */ |
| 555 |
for (i = tms->mbrmax-tms->mbrmin+1; i--; ) { |
| 556 |
j = d = (double)i/(tms->mbrmax-tms->mbrmin)*histlen; |
| 557 |
d -= (double)j; |
| 558 |
Ld = Ldmin*exp(logLddyn*((1.-d)*cumf[j]+d*cumf[j+1])); |
| 559 |
d = (Ld - Ldmin)/(Ldmax - Ldmin); |
| 560 |
tms->lumap[i] = 256.*pow(d, 1./gamval); |
| 561 |
} |
| 562 |
free((MEM_PTR)histo); /* clean up and return */ |
| 563 |
free((MEM_PTR)cumf); |
| 564 |
returnOK; |
| 565 |
linearmap: /* linear tone-mapping */ |
| 566 |
if (tms->flags & TM_F_HCONTR) |
| 567 |
d = htcontrs(Ldavg) / htcontrs(Lwavg); |
| 568 |
else |
| 569 |
d = Ldavg / Lwavg; |
| 570 |
return(tmFixedMapping(tms, tms->inpsf*d/Ldmax, gamval)); |
| 571 |
} |
| 572 |
|
| 573 |
|
| 574 |
int |
| 575 |
tmMapPixels( /* apply tone-mapping to pixel(s) */ |
| 576 |
TMstruct *tms, |
| 577 |
BYTE *ps, |
| 578 |
TMbright *ls, |
| 579 |
BYTE *cs, |
| 580 |
int len |
| 581 |
) |
| 582 |
{ |
| 583 |
static const char funcName[] = "tmMapPixels"; |
| 584 |
int32 li, pv; |
| 585 |
|
| 586 |
if (tms == NULL || tms->lumap == NULL) |
| 587 |
returnErr(TM_E_TMINVAL); |
| 588 |
if ((ps == NULL) | (ls == NULL) | (len < 0)) |
| 589 |
returnErr(TM_E_ILLEGAL); |
| 590 |
while (len--) { |
| 591 |
if ((li = *ls++) < tms->mbrmin) { |
| 592 |
li = 0; |
| 593 |
} else { |
| 594 |
if (li > tms->mbrmax) |
| 595 |
li = tms->mbrmax; |
| 596 |
li = tms->lumap[li - tms->mbrmin]; |
| 597 |
} |
| 598 |
if (cs == TM_NOCHROM) |
| 599 |
*ps++ = li>255 ? 255 : li; |
| 600 |
else { |
| 601 |
pv = *cs++ * li / tms->cdiv[RED]; |
| 602 |
*ps++ = pv>255 ? 255 : pv; |
| 603 |
pv = *cs++ * li / tms->cdiv[GRN]; |
| 604 |
*ps++ = pv>255 ? 255 : pv; |
| 605 |
pv = *cs++ * li / tms->cdiv[BLU]; |
| 606 |
*ps++ = pv>255 ? 255 : pv; |
| 607 |
} |
| 608 |
} |
| 609 |
returnOK; |
| 610 |
} |
| 611 |
|
| 612 |
|
| 613 |
|
| 614 |
|
| 615 |
TMstruct * |
| 616 |
tmDup( /* duplicate top tone mapping */ |
| 617 |
TMstruct *tms |
| 618 |
) |
| 619 |
{ |
| 620 |
int len; |
| 621 |
int i; |
| 622 |
TMstruct *tmnew; |
| 623 |
|
| 624 |
if (tms == NULL) /* anything to duplicate? */ |
| 625 |
return(NULL); |
| 626 |
tmnew = (TMstruct *)malloc(sizeof(TMstruct)); |
| 627 |
if (tmnew == NULL) |
| 628 |
return(NULL); |
| 629 |
*tmnew = *tms; /* copy everything */ |
| 630 |
if (tmnew->histo != NULL) { /* duplicate histogram */ |
| 631 |
len = (tmnew->hbrmax-MINBRT)/HISTEP + 1 - |
| 632 |
(tmnew->hbrmin-MINBRT)/HISTEP; |
| 633 |
tmnew->histo = (int *)malloc(len*sizeof(int)); |
| 634 |
if (tmnew->histo != NULL) |
| 635 |
for (i = len; i--; ) |
| 636 |
tmnew->histo[i] = tms->histo[i]; |
| 637 |
} |
| 638 |
if (tmnew->lumap != NULL) { /* duplicate luminance mapping */ |
| 639 |
len = tmnew->mbrmax-tmnew->mbrmin+1; |
| 640 |
tmnew->lumap = (unsigned short *)malloc( |
| 641 |
len*sizeof(unsigned short) ); |
| 642 |
if (tmnew->lumap != NULL) |
| 643 |
for (i = len; i--; ) |
| 644 |
tmnew->lumap[i] = tms->lumap[i]; |
| 645 |
} |
| 646 |
/* clear package data */ |
| 647 |
for (i = tmNumPkgs; i--; ) |
| 648 |
tmnew->pd[i] = NULL; |
| 649 |
/* return copy */ |
| 650 |
return(tmnew); |
| 651 |
} |
| 652 |
|
| 653 |
|
| 654 |
void |
| 655 |
tmDone(tms) /* done with tone mapping -- destroy it */ |
| 656 |
TMstruct *tms; |
| 657 |
{ |
| 658 |
int i; |
| 659 |
/* NULL arg. is equiv. to tms */ |
| 660 |
if (tms == NULL) |
| 661 |
return; |
| 662 |
/* free tables */ |
| 663 |
if (tms->histo != NULL) |
| 664 |
free((MEM_PTR)tms->histo); |
| 665 |
if (tms->lumap != NULL) |
| 666 |
free((MEM_PTR)tms->lumap); |
| 667 |
/* free private data */ |
| 668 |
for (i = tmNumPkgs; i--; ) |
| 669 |
if (tms->pd[i] != NULL) |
| 670 |
(*tmPkg[i]->Free)(tms->pd[i]); |
| 671 |
free((MEM_PTR)tms); /* free basic structure */ |
| 672 |
} |
| 673 |
|
| 674 |
/******************** Shared but Private library routines *********************/ |
| 675 |
|
| 676 |
BYTE tmMesofact[BMESUPPER-BMESLOWER]; |
| 677 |
|
| 678 |
void |
| 679 |
tmMkMesofact() /* build mesopic lookup factor table */ |
| 680 |
{ |
| 681 |
int i; |
| 682 |
|
| 683 |
if (tmMesofact[BMESUPPER-BMESLOWER-1]) |
| 684 |
return; |
| 685 |
|
| 686 |
for (i = BMESLOWER; i < BMESUPPER; i++) |
| 687 |
tmMesofact[i-BMESLOWER] = 256. * |
| 688 |
(tmLuminance(i) - LMESLOWER) / |
| 689 |
(LMESUPPER - LMESLOWER); |
| 690 |
} |
| 691 |
|
| 692 |
|
| 693 |
int |
| 694 |
tmErrorReturn( /* error return (with message) */ |
| 695 |
const char *func, |
| 696 |
TMstruct *tms, |
| 697 |
int err |
| 698 |
) |
| 699 |
{ |
| 700 |
if (tms != NULL) { |
| 701 |
tms->lastFunc = func; |
| 702 |
tms->lastError = err; |
| 703 |
if (tms->flags & TM_F_NOSTDERR) |
| 704 |
return(err); |
| 705 |
} |
| 706 |
fputs(func, stderr); |
| 707 |
fputs(": ", stderr); |
| 708 |
fputs(tmErrorMessage[err], stderr); |
| 709 |
fputs("!\n", stderr); |
| 710 |
return(err); |
| 711 |
} |
