1 |
/* RCSid $Id: tonemap.h,v 3.13 2003/06/06 16:38:47 schorsch Exp $ */ |
2 |
/* |
3 |
* Header file for tone mapping functions. |
4 |
* |
5 |
* Include after "color.h" |
6 |
*/ |
7 |
#ifndef _RAD_TONEMAP_H_ |
8 |
#define _RAD_TONEMAP_H_ |
9 |
#ifdef __cplusplus |
10 |
extern "C" { |
11 |
#endif |
12 |
|
13 |
/**** Argument Macros ****/ |
14 |
/* Flags of what to do */ |
15 |
#define TM_F_HCONTR 01 /* human contrast sensitivity */ |
16 |
#define TM_F_MESOPIC 02 /* mesopic color sensitivity */ |
17 |
#define TM_F_LINEAR 04 /* linear brightness mapping */ |
18 |
#define TM_F_ACUITY 010 /* acuity adjustment */ |
19 |
#define TM_F_VEIL 020 /* veiling glare */ |
20 |
#define TM_F_CWEIGHT 040 /* center weighting */ |
21 |
#define TM_F_FOVEAL 0100 /* use foveal sample size */ |
22 |
#define TM_F_BW 0200 /* luminance only */ |
23 |
#define TM_F_NOSTDERR 0400 /* don't report errors to stderr */ |
24 |
/* combined modes */ |
25 |
#define TM_F_CAMERA 0 |
26 |
#define TM_F_HUMAN (TM_F_HCONTR|TM_F_MESOPIC|TM_F_VEIL|\ |
27 |
TM_F_ACUITY|TM_F_FOVEAL) |
28 |
#define TM_F_UNIMPL (TM_F_CWEIGHT|TM_F_VEIL|TM_F_ACUITY|TM_F_FOVEAL) |
29 |
|
30 |
/* special pointer values */ |
31 |
#define TM_XYZPRIM (RGBPRIMP)NULL /* indicate XYZ primaries (Note 1) */ |
32 |
#define TM_NOCHROM (BYTE *)NULL /* indicate no chrominance */ |
33 |
#define TM_NOCHROMP (BYTE **)NULL /* indicate no chrominances */ |
34 |
#define TM_GETFILE (FILE *)NULL /* indicate file must be opened */ |
35 |
|
36 |
|
37 |
/**** Error Return Values ****/ |
38 |
|
39 |
#define TM_E_OK 0 /* normal return status */ |
40 |
#define TM_E_NOMEM 1 /* out of memory */ |
41 |
#define TM_E_ILLEGAL 2 /* illegal argument value */ |
42 |
#define TM_E_TMINVAL 3 /* no valid tone mapping */ |
43 |
#define TM_E_TMFAIL 4 /* cannot compute tone mapping */ |
44 |
#define TM_E_BADFILE 5 /* cannot open or understand file */ |
45 |
#define TM_E_CODERR1 6 /* code consistency error 1 */ |
46 |
#define TM_E_CODERR2 7 /* code consistency error 2 */ |
47 |
|
48 |
|
49 |
/**** Conversion Constants and Table Sizes ****/ |
50 |
|
51 |
#define TM_BRTSCALE 128 /* brightness scale factor (integer) */ |
52 |
|
53 |
#define TM_NOBRT (-1<<15) /* bogus brightness value */ |
54 |
#define TM_NOLUM (1e-17) /* ridiculously small luminance */ |
55 |
|
56 |
#define TM_MAXPKG 8 /* maximum number of color formats */ |
57 |
|
58 |
|
59 |
/**** Global Data Types and Structures ****/ |
60 |
|
61 |
#ifndef MEM_PTR |
62 |
#define MEM_PTR void * |
63 |
#endif |
64 |
|
65 |
extern char *tmErrorMessage[]; /* error messages */ |
66 |
extern int tmLastError; /* last error incurred by library */ |
67 |
extern char *tmLastFunction; /* error-generating function name */ |
68 |
|
69 |
typedef short TMbright; /* encoded luminance type */ |
70 |
|
71 |
/* basic tone mapping data structure */ |
72 |
extern struct tmStruct { |
73 |
int flags; /* flags of what to do */ |
74 |
RGBPRIMP monpri; /* monitor RGB primaries */ |
75 |
double mongam; /* monitor gamma value (approx.) */ |
76 |
COLOR clf; /* computed luminance coefficients */ |
77 |
int cdiv[3]; /* computed color divisors */ |
78 |
RGBPRIMP inppri; /* current input primaries */ |
79 |
double inpsf; /* current input scalefactor */ |
80 |
COLORMAT cmat; /* color conversion matrix */ |
81 |
TMbright hbrmin, hbrmax; /* histogram brightness limits */ |
82 |
int *histo; /* input histogram */ |
83 |
TMbright mbrmin, mbrmax; /* mapped brightness limits */ |
84 |
unsigned short *lumap; /* computed luminance map */ |
85 |
struct tmStruct *tmprev; /* previous tone mapping */ |
86 |
MEM_PTR pd[TM_MAXPKG]; /* pointers to private data */ |
87 |
} *tmTop; /* current tone mapping stack */ |
88 |
|
89 |
/* conversion package functions */ |
90 |
struct tmPackage { |
91 |
MEM_PTR (*Init)(struct tmStruct *tms); |
92 |
void (*NewSpace)(struct tmStruct *tms); |
93 |
void (*Free)(MEM_PTR pp); |
94 |
}; |
95 |
/* our list of conversion packages */ |
96 |
extern struct tmPackage *tmPkg[TM_MAXPKG]; |
97 |
extern int tmNumPkgs; /* number of registered packages */ |
98 |
|
99 |
|
100 |
/**** Useful Macros ****/ |
101 |
|
102 |
/* compute luminance from encoded value */ |
103 |
#define tmLuminance(li) exp((li)*(1./TM_BRTSCALE)) |
104 |
|
105 |
/* does tone mapping need color matrix? */ |
106 |
#define tmNeedMatrix(t) ((t)->monpri != (t)->inppri) |
107 |
|
108 |
/* register a conversion package */ |
109 |
#define tmRegPkg(pf) ( tmNumPkgs >= TM_MAXPKG ? -1 : \ |
110 |
(tmPkg[tmNumPkgs] = (pf), tmNumPkgs++) ) |
111 |
|
112 |
/* get the specific package's data */ |
113 |
#define tmPkgData(t,i) ((t)->pd[i]!=NULL ? (t)->pd[i] : (*tmPkg[i]->Init)(t)) |
114 |
|
115 |
|
116 |
/**** Library Function Calls ****/ |
117 |
|
118 |
|
119 |
extern struct tmStruct * |
120 |
tmInit(int flags, RGBPRIMP monpri, double gamval); |
121 |
/* |
122 |
Initialize new tone mapping and push it onto stack. |
123 |
|
124 |
flags - TM_F_* flags indicating what is to be done. |
125 |
monpri - display monitor primaries (Note 1). |
126 |
gamval - display gamma response (can be approximate). |
127 |
|
128 |
returns - new tmTop, or NULL if insufficient memory. |
129 |
*/ |
130 |
|
131 |
extern int |
132 |
tmSetSpace(RGBPRIMP pri, double sf); |
133 |
/* |
134 |
Set color primaries and scale factor for incoming scanlines. |
135 |
|
136 |
pri - RGB color input primaries (Note 1). |
137 |
sf - scale factor to get to luminance in cd/m^2. |
138 |
|
139 |
returns - 0 on success, TM_E_* code on failure. |
140 |
*/ |
141 |
|
142 |
extern void |
143 |
tmClearHisto(void); |
144 |
/* |
145 |
Clear histogram for current tone mapping. |
146 |
*/ |
147 |
|
148 |
extern int |
149 |
tmAddHisto(TMbright *ls, int len, int wt); |
150 |
/* |
151 |
Add brightness values to current histogram. |
152 |
|
153 |
ls - encoded luminance values. |
154 |
len - number of luminance values. |
155 |
wt - integer weight to use for each value (usually 1 or -1). |
156 |
|
157 |
returns - 0 on success, TM_E_* on error. |
158 |
*/ |
159 |
|
160 |
extern int |
161 |
tmFixedMapping(double expmult, double gamval); |
162 |
/* |
163 |
Assign a fixed, linear tone-mapping using the given multiplier, |
164 |
which is the ratio of maximum output to uncalibrated input. |
165 |
This mapping will be used in subsequent calls to tmMapPixels() |
166 |
until a new tone mapping is computed. |
167 |
Only the min. and max. values are used from the histogram. |
168 |
|
169 |
expmult - the fixed exposure multiplier to use. |
170 |
gamval - display gamma response (0. for default). |
171 |
returns - 0 on success, TM_E_* on error. |
172 |
*/ |
173 |
|
174 |
extern int |
175 |
tmComputeMapping(double gamval, double Lddyn, double Ldmax); |
176 |
/* |
177 |
Compute tone mapping function from the current histogram. |
178 |
This mapping will be used in subsequent calls to tmMapPixels() |
179 |
until a new tone mapping is computed. |
180 |
I.e., calls to tmAddHisto() have no immediate effect. |
181 |
|
182 |
gamval - display gamma response (0. for default). |
183 |
Lddyn - the display's dynamic range (0. for default). |
184 |
Ldmax - maximum display luminance in cd/m^2 (0. for default). |
185 |
|
186 |
returns - 0 on success, TM_E_* on failure. |
187 |
*/ |
188 |
|
189 |
extern int |
190 |
tmMapPixels(BYTE *ps, TMbright *ls, BYTE *cs, int len); |
191 |
/* |
192 |
Apply tone mapping function to pixel values. |
193 |
|
194 |
ps - returned pixel values (Note 2). |
195 |
ls - encoded luminance values. |
196 |
cs - encoded chrominance values (Note 2). |
197 |
len - number of pixels. |
198 |
|
199 |
returns - 0 on success, TM_E_* on failure. |
200 |
*/ |
201 |
|
202 |
extern struct tmStruct * |
203 |
tmPop(void); |
204 |
/* |
205 |
Pops current tone mapping from stack. |
206 |
|
207 |
returns - pointer to tone mapping structure, or NULL if none. |
208 |
*/ |
209 |
|
210 |
extern int |
211 |
tmPull(struct tmStruct *tms); |
212 |
/* |
213 |
Pull tone mapping from anywhere in stack. |
214 |
|
215 |
tms - tone mapping structure to find. |
216 |
|
217 |
returns - 1 if found in stack, 0 otherwise. |
218 |
*/ |
219 |
|
220 |
extern int |
221 |
tmPush(struct tmStruct *tms); |
222 |
/* |
223 |
Make tone mapping active by (pulling it and) pushing it to the top. |
224 |
|
225 |
tms - initialized tone mapping structure. |
226 |
|
227 |
returns - 0 on success, TM_E_* if tms is invalid. |
228 |
*/ |
229 |
|
230 |
extern struct tmStruct * |
231 |
tmDup(void); |
232 |
/* |
233 |
Duplicate the current tone mapping into a new structure on the stack. |
234 |
|
235 |
returns - pointer to new top, or NULL on error. |
236 |
*/ |
237 |
|
238 |
extern void |
239 |
tmDone(struct tmStruct *tms); |
240 |
/* |
241 |
Free data associated with the given tone mapping structure. |
242 |
Calls tmPull() first to remove it from the stack if present. |
243 |
The calls tmDone(tmPop()), tmDone(tmTop) and tmDone(NULL) |
244 |
all have the same effect, which is to remove and free |
245 |
the current tone mapping. |
246 |
|
247 |
tms - tone mapping structure to free. |
248 |
*/ |
249 |
|
250 |
extern int |
251 |
tmCvColors(TMbright *ls, BYTE *cs, COLOR *scan, int len); |
252 |
/* |
253 |
Convert RGB/XYZ float scanline to encoded luminance and chrominance. |
254 |
|
255 |
ls - returned encoded luminance values. |
256 |
cs - returned encoded chrominance values (Note 2). |
257 |
scan - input scanline. |
258 |
len - scanline length. |
259 |
|
260 |
returns - 0 on success, TM_E_* on error. |
261 |
*/ |
262 |
|
263 |
extern int |
264 |
tmCvGrays(TMbright *ls, float *scan, int len); |
265 |
/* |
266 |
Convert gray float scanline to encoded luminance. |
267 |
|
268 |
ls - returned encoded luminance values. |
269 |
scan - input scanline. |
270 |
len - scanline length. |
271 |
|
272 |
returns - 0 on success, TM_E_* on error. |
273 |
*/ |
274 |
|
275 |
extern int |
276 |
tmCvColrs(TMbright *ls, BYTE *cs, COLR *scan, int len); |
277 |
/* |
278 |
Convert RGBE/XYZE scanline to encoded luminance and chrominance. |
279 |
|
280 |
ls - returned encoded luminance values. |
281 |
cs - returned encoded chrominance values (Note 2). |
282 |
scan - input scanline. |
283 |
len - scanline length. |
284 |
|
285 |
returns - 0 on success, TM_E_* on error. |
286 |
*/ |
287 |
|
288 |
extern int |
289 |
tmLoadPicture(TMbright **lpp, BYTE **cpp, int *xp, int *yp, |
290 |
char *fname, FILE *fp); |
291 |
/* |
292 |
Load Radiance picture and convert to tone mapping representation. |
293 |
Memory for the luminance and chroma arrays is allocated using |
294 |
malloc(3), and should be freed with free(3) when no longer needed. |
295 |
Calls tmSetSpace() to calibrate input color space. |
296 |
|
297 |
lpp - returned array of encoded luminances, picture ordering. |
298 |
cpp - returned array of encoded chrominances (Note 2). |
299 |
xp, yp - returned picture dimensions. |
300 |
fname - picture file name. |
301 |
fp - pointer to open file (Note 3). |
302 |
|
303 |
returns - 0 on success, TM_E_* on failure. |
304 |
*/ |
305 |
|
306 |
extern int |
307 |
tmMapPicture(BYTE **psp, int *xp, int *yp, int flags, |
308 |
RGBPRIMP monpri, double gamval, double Lddyn, double Ldmax, |
309 |
char *fname, FILE *fp); |
310 |
/* |
311 |
Load and apply tone mapping to Radiance picture. |
312 |
Stack is restored to its original state upon return. |
313 |
If fp is TM_GETFILE and (flags&TM_F_UNIMPL)!=0, tmMapPicture() |
314 |
calls pcond to perform the actual conversion, which takes |
315 |
longer but gives access to all the TM_F_* features. |
316 |
Memory for the final pixel array is allocated using malloc(3), |
317 |
and should be freed with free(3) when it is no longer needed. |
318 |
|
319 |
psp - returned array of tone mapped pixels, picture ordering. |
320 |
xp, yp - returned picture dimensions. |
321 |
flags - TM_F_* flags indicating what is to be done. |
322 |
monpri - display monitor primaries (Note 1). |
323 |
gamval - display gamma response. |
324 |
Lddyn - the display's dynamic range (0. for default). |
325 |
Ldmax - maximum display luminance in cd/m^2 (0. for default). |
326 |
fname - picture file name. |
327 |
fp - pointer to open file (Note 3). |
328 |
|
329 |
returns - 0 on success, TM_E_* on failure. |
330 |
*/ |
331 |
|
332 |
|
333 |
|
334 |
/**** Notes ****/ |
335 |
/* |
336 |
General: |
337 |
|
338 |
The usual sequence after calling tmInit() is to convert some |
339 |
pixel values to chroma and luminance encodings, which can |
340 |
be passed to tmAddHisto() to put into the tone mapping histogram. |
341 |
This histogram is then used along with the display parameters |
342 |
by tmComputeMapping() to compute the luminance mapping function. |
343 |
(Colors are tone-mapped as they are converted if TM_F_MESOPIC |
344 |
is set.) The encoded chroma and luminance values may then be |
345 |
passed to tmMapPixels() to apply the computed tone mapping in |
346 |
a second pass. |
347 |
|
348 |
Especially for RGBE colors in the same color space as the |
349 |
target display, the conversion to chroma and luminance values |
350 |
is fast enough that it may be recomputed on the second pass |
351 |
if memory is at a premium. (Since the chroma values are only |
352 |
used during final mapping, setting the cs parameter to TM_NOCHROM |
353 |
on the first pass will save time.) Another memory saving option |
354 |
if third and subsequent passes are not needed is to use the |
355 |
same array to store the mapped pixels as used to store |
356 |
the encoded chroma values. This way, only two extra bytes |
357 |
for storing encoded luminances are required per pixel. This |
358 |
is the method employed by tmMapPicture(), for example. |
359 |
*/ |
360 |
/* |
361 |
Note 1: |
362 |
|
363 |
All RGBPRIMP values should be pointers to static structures. |
364 |
I.e., the same pointer should be used for the same primaries, |
365 |
and those primaries should not change from one call to the next. |
366 |
This is because the routines use the pointer value to identify |
367 |
computed conversion matrices, so the matrices do not have to be |
368 |
rebuilt each time. If you are using the standard primaries, |
369 |
use the standard primary pointer, stdprims. |
370 |
|
371 |
To indicate a set of input primaries are actually CIE XYZ, |
372 |
the TM_XYZPRIM macro may be passed. If the input primaries |
373 |
are unknown, it is wisest to pass tmTop->monpri to tmSetSpace(). |
374 |
By default, the input primaries equal the monitor primaries |
375 |
and the scalefactor is set to WHTEFFICACY in tmInit(). |
376 |
*/ |
377 |
/* |
378 |
Note 2: |
379 |
|
380 |
Chrominance is optional in most of these routines, whether |
381 |
TM_F_BW is set or not. Passing a value of TM_NOCHROM (or |
382 |
TM_NOCHROMP for picture reading) indicates that returned |
383 |
color values are not desired. |
384 |
|
385 |
If TM_NOCHROM is passed to a mapping routine expecting chroma |
386 |
input, it will do without it and return luminance channel |
387 |
rather than RGB pixel values. Otherwise, the array for |
388 |
returned pixel values may be the same array used to pass |
389 |
encoded chrominances if no other mappings are desired. |
390 |
*/ |
391 |
/* |
392 |
Note 3: |
393 |
|
394 |
Picture files may either be opened by the calling routine or by |
395 |
the library function. If opened by the calling routine, the |
396 |
pointer to the stream is passed, which may be a pipe or other |
397 |
non-seekable input as it is only read once. It must be |
398 |
positioned at the beginning when the function is called, and it |
399 |
will be positioned at the end on return. It will not be closed. |
400 |
If the passed stream pointer is TM_GETFILE, then the library |
401 |
function will open the file, read its contents and close it |
402 |
before returning, whether or not an error was encountered. |
403 |
*/ |
404 |
|
405 |
#ifdef __cplusplus |
406 |
} |
407 |
#endif |
408 |
#endif /* _RAD_TONEMAP_H_ */ |
409 |
|