1 |
greg |
3.26 |
/* RCSid $Id: tonemap.h,v 3.25 2010/08/18 15:25:03 greg Exp $ */ |
2 |
greg |
3.1 |
/* |
3 |
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* Header file for tone mapping functions. |
4 |
gwlarson |
3.8 |
* |
5 |
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* Include after "color.h" |
6 |
greg |
3.1 |
*/ |
7 |
schorsch |
3.13 |
#ifndef _RAD_TONEMAP_H_ |
8 |
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#define _RAD_TONEMAP_H_ |
9 |
schorsch |
3.16 |
|
10 |
greg |
3.23 |
#include "tiff.h" /* needed for int32, etc. */ |
11 |
schorsch |
3.16 |
|
12 |
greg |
3.11 |
#ifdef __cplusplus |
13 |
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extern "C" { |
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#endif |
15 |
greg |
3.15 |
|
16 |
greg |
3.1 |
/**** Argument Macros ****/ |
17 |
greg |
3.20 |
/* flags of what to do */ |
18 |
greg |
3.1 |
#define TM_F_HCONTR 01 /* human contrast sensitivity */ |
19 |
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#define TM_F_MESOPIC 02 /* mesopic color sensitivity */ |
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#define TM_F_LINEAR 04 /* linear brightness mapping */ |
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#define TM_F_ACUITY 010 /* acuity adjustment */ |
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#define TM_F_VEIL 020 /* veiling glare */ |
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#define TM_F_CWEIGHT 040 /* center weighting */ |
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#define TM_F_FOVEAL 0100 /* use foveal sample size */ |
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#define TM_F_BW 0200 /* luminance only */ |
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greg |
3.2 |
#define TM_F_NOSTDERR 0400 /* don't report errors to stderr */ |
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greg |
3.1 |
/* combined modes */ |
28 |
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#define TM_F_CAMERA 0 |
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#define TM_F_HUMAN (TM_F_HCONTR|TM_F_MESOPIC|TM_F_VEIL|\ |
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TM_F_ACUITY|TM_F_FOVEAL) |
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#define TM_F_UNIMPL (TM_F_CWEIGHT|TM_F_VEIL|TM_F_ACUITY|TM_F_FOVEAL) |
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33 |
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/* special pointer values */ |
34 |
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#define TM_XYZPRIM (RGBPRIMP)NULL /* indicate XYZ primaries (Note 1) */ |
35 |
greg |
3.26 |
#define TM_NOCHROM (uby8 *)NULL /* indicate no chrominance */ |
36 |
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#define TM_NOCHROMP (uby8 **)NULL /* indicate no chrominances */ |
37 |
greg |
3.1 |
#define TM_GETFILE (FILE *)NULL /* indicate file must be opened */ |
38 |
gwlarson |
3.8 |
|
39 |
greg |
3.1 |
|
40 |
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/**** Error Return Values ****/ |
41 |
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42 |
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#define TM_E_OK 0 /* normal return status */ |
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#define TM_E_NOMEM 1 /* out of memory */ |
44 |
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#define TM_E_ILLEGAL 2 /* illegal argument value */ |
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#define TM_E_TMINVAL 3 /* no valid tone mapping */ |
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#define TM_E_TMFAIL 4 /* cannot compute tone mapping */ |
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#define TM_E_BADFILE 5 /* cannot open or understand file */ |
48 |
greg |
3.4 |
#define TM_E_CODERR1 6 /* code consistency error 1 */ |
49 |
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#define TM_E_CODERR2 7 /* code consistency error 2 */ |
50 |
greg |
3.1 |
|
51 |
greg |
3.4 |
|
52 |
greg |
3.1 |
/**** Conversion Constants and Table Sizes ****/ |
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54 |
greg |
3.25 |
#define TM_BRTSCALE 256 /* brightness scale factor (integer) */ |
55 |
greg |
3.1 |
|
56 |
gwlarson |
3.10 |
#define TM_NOBRT (-1<<15) /* bogus brightness value */ |
57 |
greg |
3.11 |
#define TM_NOLUM (1e-17) /* ridiculously small luminance */ |
58 |
gwlarson |
3.10 |
|
59 |
greg |
3.4 |
#define TM_MAXPKG 8 /* maximum number of color formats */ |
60 |
greg |
3.1 |
|
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greg |
3.4 |
/**** Global Data Types and Structures ****/ |
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#ifndef MEM_PTR |
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#define MEM_PTR void * |
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#endif |
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greg |
3.1 |
extern char *tmErrorMessage[]; /* error messages */ |
69 |
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typedef short TMbright; /* encoded luminance type */ |
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/* basic tone mapping data structure */ |
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greg |
3.20 |
typedef struct { |
74 |
greg |
3.1 |
int flags; /* flags of what to do */ |
75 |
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RGBPRIMP monpri; /* monitor RGB primaries */ |
76 |
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double mongam; /* monitor gamma value (approx.) */ |
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COLOR clf; /* computed luminance coefficients */ |
78 |
greg |
3.4 |
int cdiv[3]; /* computed color divisors */ |
79 |
greg |
3.1 |
RGBPRIMP inppri; /* current input primaries */ |
80 |
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double inpsf; /* current input scalefactor */ |
81 |
greg |
3.19 |
MEM_PTR inpdat; /* current input client data */ |
82 |
greg |
3.1 |
COLORMAT cmat; /* color conversion matrix */ |
83 |
gregl |
3.7 |
TMbright hbrmin, hbrmax; /* histogram brightness limits */ |
84 |
greg |
3.1 |
int *histo; /* input histogram */ |
85 |
gregl |
3.7 |
TMbright mbrmin, mbrmax; /* mapped brightness limits */ |
86 |
greg |
3.1 |
unsigned short *lumap; /* computed luminance map */ |
87 |
greg |
3.4 |
MEM_PTR pd[TM_MAXPKG]; /* pointers to private data */ |
88 |
greg |
3.18 |
int lastError; /* last error incurred */ |
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const char *lastFunc; /* error-generating function name */ |
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greg |
3.17 |
} TMstruct; |
91 |
greg |
3.4 |
|
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/* conversion package functions */ |
93 |
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struct tmPackage { |
94 |
greg |
3.17 |
MEM_PTR (*Init)(TMstruct *tms); |
95 |
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void (*NewSpace)(TMstruct *tms); |
96 |
greg |
3.4 |
void (*Free)(MEM_PTR pp); |
97 |
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}; |
98 |
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/* our list of conversion packages */ |
99 |
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extern struct tmPackage *tmPkg[TM_MAXPKG]; |
100 |
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extern int tmNumPkgs; /* number of registered packages */ |
101 |
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102 |
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103 |
greg |
3.1 |
/**** Useful Macros ****/ |
104 |
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105 |
greg |
3.4 |
/* compute luminance from encoded value */ |
106 |
greg |
3.11 |
#define tmLuminance(li) exp((li)*(1./TM_BRTSCALE)) |
107 |
greg |
3.1 |
|
108 |
greg |
3.4 |
/* does tone mapping need color matrix? */ |
109 |
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#define tmNeedMatrix(t) ((t)->monpri != (t)->inppri) |
110 |
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111 |
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/* register a conversion package */ |
112 |
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#define tmRegPkg(pf) ( tmNumPkgs >= TM_MAXPKG ? -1 : \ |
113 |
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(tmPkg[tmNumPkgs] = (pf), tmNumPkgs++) ) |
114 |
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115 |
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/* get the specific package's data */ |
116 |
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#define tmPkgData(t,i) ((t)->pd[i]!=NULL ? (t)->pd[i] : (*tmPkg[i]->Init)(t)) |
117 |
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118 |
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119 |
greg |
3.1 |
/**** Library Function Calls ****/ |
120 |
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121 |
greg |
3.21 |
extern TMbright |
122 |
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tmCvLuminance(double lum); |
123 |
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/* |
124 |
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Convert a single luminance value to an encoded brightness value. |
125 |
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*/ |
126 |
greg |
3.1 |
|
127 |
greg |
3.22 |
extern int |
128 |
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tmCvLums(TMbright *ls, float *scan, int len); |
129 |
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/* |
130 |
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Convert luminance values to encoded brightness values using lookup. |
131 |
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132 |
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ls - returned encoded luminance values. |
133 |
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scan - input scanline. |
134 |
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len - scanline length. |
135 |
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136 |
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returns - 0 on success, TM_E_* on error. |
137 |
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*/ |
138 |
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139 |
greg |
3.17 |
extern TMstruct * |
140 |
greg |
3.1 |
tmInit(int flags, RGBPRIMP monpri, double gamval); |
141 |
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/* |
142 |
greg |
3.17 |
Allocate and initialize new tone mapping. |
143 |
greg |
3.1 |
|
144 |
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flags - TM_F_* flags indicating what is to be done. |
145 |
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monpri - display monitor primaries (Note 1). |
146 |
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gamval - display gamma response (can be approximate). |
147 |
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148 |
greg |
3.17 |
returns - new tone-mapping pointer, or NULL if no memory. |
149 |
greg |
3.1 |
*/ |
150 |
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151 |
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extern int |
152 |
greg |
3.19 |
tmSetSpace(TMstruct *tms, RGBPRIMP pri, double sf, MEM_PTR dat); |
153 |
greg |
3.1 |
/* |
154 |
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Set color primaries and scale factor for incoming scanlines. |
155 |
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156 |
greg |
3.17 |
tms - tone mapping structure pointer. |
157 |
greg |
3.1 |
pri - RGB color input primaries (Note 1). |
158 |
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sf - scale factor to get to luminance in cd/m^2. |
159 |
greg |
3.19 |
dat - application-specific data (NULL if not needed) |
160 |
greg |
3.1 |
|
161 |
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returns - 0 on success, TM_E_* code on failure. |
162 |
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*/ |
163 |
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164 |
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extern void |
165 |
greg |
3.17 |
tmClearHisto(TMstruct *tms); |
166 |
greg |
3.1 |
/* |
167 |
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Clear histogram for current tone mapping. |
168 |
greg |
3.17 |
|
169 |
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tms - tone mapping structure pointer. |
170 |
greg |
3.1 |
*/ |
171 |
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172 |
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extern int |
173 |
greg |
3.17 |
tmAddHisto(TMstruct *tms, TMbright *ls, int len, int wt); |
174 |
greg |
3.1 |
/* |
175 |
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Add brightness values to current histogram. |
176 |
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|
177 |
greg |
3.17 |
tms - tone mapping structure pointer. |
178 |
greg |
3.1 |
ls - encoded luminance values. |
179 |
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len - number of luminance values. |
180 |
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wt - integer weight to use for each value (usually 1 or -1). |
181 |
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182 |
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returns - 0 on success, TM_E_* on error. |
183 |
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*/ |
184 |
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185 |
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extern int |
186 |
greg |
3.17 |
tmFixedMapping(TMstruct *tms, double expmult, double gamval); |
187 |
greg |
3.11 |
/* |
188 |
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Assign a fixed, linear tone-mapping using the given multiplier, |
189 |
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which is the ratio of maximum output to uncalibrated input. |
190 |
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This mapping will be used in subsequent calls to tmMapPixels() |
191 |
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until a new tone mapping is computed. |
192 |
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Only the min. and max. values are used from the histogram. |
193 |
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194 |
greg |
3.17 |
tms - tone mapping structure pointer. |
195 |
greg |
3.11 |
expmult - the fixed exposure multiplier to use. |
196 |
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gamval - display gamma response (0. for default). |
197 |
greg |
3.18 |
|
198 |
greg |
3.11 |
returns - 0 on success, TM_E_* on error. |
199 |
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*/ |
200 |
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201 |
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extern int |
202 |
greg |
3.17 |
tmComputeMapping(TMstruct *tms, double gamval, double Lddyn, double Ldmax); |
203 |
greg |
3.1 |
/* |
204 |
greg |
3.11 |
Compute tone mapping function from the current histogram. |
205 |
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This mapping will be used in subsequent calls to tmMapPixels() |
206 |
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until a new tone mapping is computed. |
207 |
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I.e., calls to tmAddHisto() have no immediate effect. |
208 |
greg |
3.1 |
|
209 |
greg |
3.17 |
tms - tone mapping structure pointer. |
210 |
greg |
3.1 |
gamval - display gamma response (0. for default). |
211 |
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Lddyn - the display's dynamic range (0. for default). |
212 |
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Ldmax - maximum display luminance in cd/m^2 (0. for default). |
213 |
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214 |
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returns - 0 on success, TM_E_* on failure. |
215 |
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*/ |
216 |
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217 |
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extern int |
218 |
greg |
3.26 |
tmMapPixels(TMstruct *tms, uby8 *ps, TMbright *ls, uby8 *cs, int len); |
219 |
greg |
3.1 |
/* |
220 |
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Apply tone mapping function to pixel values. |
221 |
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222 |
greg |
3.17 |
tms - tone mapping structure pointer. |
223 |
greg |
3.1 |
ps - returned pixel values (Note 2). |
224 |
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ls - encoded luminance values. |
225 |
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cs - encoded chrominance values (Note 2). |
226 |
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len - number of pixels. |
227 |
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228 |
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returns - 0 on success, TM_E_* on failure. |
229 |
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*/ |
230 |
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231 |
greg |
3.17 |
extern TMstruct * |
232 |
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tmDup(TMstruct *orig); |
233 |
greg |
3.3 |
/* |
234 |
greg |
3.17 |
Duplicate the given tone mapping into a new struct. |
235 |
greg |
3.3 |
|
236 |
greg |
3.17 |
orig - tone mapping structure to duplicate. |
237 |
greg |
3.18 |
|
238 |
greg |
3.17 |
returns - pointer to new struct, or NULL on error. |
239 |
greg |
3.3 |
*/ |
240 |
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241 |
greg |
3.1 |
extern void |
242 |
greg |
3.17 |
tmDone(TMstruct *tms); |
243 |
greg |
3.1 |
/* |
244 |
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Free data associated with the given tone mapping structure. |
245 |
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246 |
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tms - tone mapping structure to free. |
247 |
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*/ |
248 |
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249 |
greg |
3.11 |
extern int |
250 |
greg |
3.22 |
tmCvGrays(TMstruct *tms, TMbright *ls, float *scan, int len); |
251 |
greg |
3.11 |
/* |
252 |
greg |
3.22 |
Convert gray float scanline to encoded luminance. |
253 |
greg |
3.11 |
|
254 |
greg |
3.17 |
tms - tone mapping structure pointer. |
255 |
greg |
3.11 |
ls - returned encoded luminance values. |
256 |
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scan - input scanline. |
257 |
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len - scanline length. |
258 |
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259 |
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returns - 0 on success, TM_E_* on error. |
260 |
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*/ |
261 |
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262 |
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extern int |
263 |
greg |
3.26 |
tmCvColors(TMstruct *tms, TMbright *ls, uby8 *cs, COLOR *scan, int len); |
264 |
greg |
3.11 |
/* |
265 |
greg |
3.22 |
Convert RGB/XYZ float scanline to encoded luminance and chrominance. |
266 |
greg |
3.11 |
|
267 |
greg |
3.17 |
tms - tone mapping structure pointer. |
268 |
greg |
3.11 |
ls - returned encoded luminance values. |
269 |
greg |
3.22 |
cs - returned encoded chrominance values (Note 2). |
270 |
greg |
3.11 |
scan - input scanline. |
271 |
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len - scanline length. |
272 |
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273 |
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returns - 0 on success, TM_E_* on error. |
274 |
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*/ |
275 |
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276 |
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extern int |
277 |
greg |
3.26 |
tmCvColrs(TMstruct *tms, TMbright *ls, uby8 *cs, COLR *scan, int len); |
278 |
greg |
3.11 |
/* |
279 |
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Convert RGBE/XYZE scanline to encoded luminance and chrominance. |
280 |
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|
281 |
greg |
3.17 |
tms - tone mapping structure pointer. |
282 |
greg |
3.11 |
ls - returned encoded luminance values. |
283 |
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cs - returned encoded chrominance values (Note 2). |
284 |
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scan - input scanline. |
285 |
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len - scanline length. |
286 |
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287 |
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returns - 0 on success, TM_E_* on error. |
288 |
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*/ |
289 |
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290 |
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extern int |
291 |
greg |
3.26 |
tmLoadPicture(TMstruct *tms, TMbright **lpp, uby8 **cpp, int *xp, int *yp, |
292 |
greg |
3.11 |
char *fname, FILE *fp); |
293 |
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/* |
294 |
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Load Radiance picture and convert to tone mapping representation. |
295 |
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Memory for the luminance and chroma arrays is allocated using |
296 |
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malloc(3), and should be freed with free(3) when no longer needed. |
297 |
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Calls tmSetSpace() to calibrate input color space. |
298 |
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|
299 |
greg |
3.17 |
tms - tone mapping structure pointer. |
300 |
greg |
3.11 |
lpp - returned array of encoded luminances, picture ordering. |
301 |
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cpp - returned array of encoded chrominances (Note 2). |
302 |
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xp, yp - returned picture dimensions. |
303 |
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fname - picture file name. |
304 |
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fp - pointer to open file (Note 3). |
305 |
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306 |
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returns - 0 on success, TM_E_* on failure. |
307 |
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*/ |
308 |
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309 |
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extern int |
310 |
greg |
3.26 |
tmMapPicture(uby8 **psp, int *xp, int *yp, int flags, |
311 |
greg |
3.11 |
RGBPRIMP monpri, double gamval, double Lddyn, double Ldmax, |
312 |
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char *fname, FILE *fp); |
313 |
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/* |
314 |
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Load and apply tone mapping to Radiance picture. |
315 |
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If fp is TM_GETFILE and (flags&TM_F_UNIMPL)!=0, tmMapPicture() |
316 |
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calls pcond to perform the actual conversion, which takes |
317 |
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longer but gives access to all the TM_F_* features. |
318 |
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Memory for the final pixel array is allocated using malloc(3), |
319 |
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and should be freed with free(3) when it is no longer needed. |
320 |
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321 |
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psp - returned array of tone mapped pixels, picture ordering. |
322 |
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xp, yp - returned picture dimensions. |
323 |
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flags - TM_F_* flags indicating what is to be done. |
324 |
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monpri - display monitor primaries (Note 1). |
325 |
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gamval - display gamma response. |
326 |
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Lddyn - the display's dynamic range (0. for default). |
327 |
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Ldmax - maximum display luminance in cd/m^2 (0. for default). |
328 |
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fname - picture file name. |
329 |
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fp - pointer to open file (Note 3). |
330 |
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331 |
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returns - 0 on success, TM_E_* on failure. |
332 |
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*/ |
333 |
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|
334 |
greg |
3.15 |
extern int |
335 |
greg |
3.26 |
tmCvRGB48(TMstruct *tms, TMbright *ls, uby8 *cs, uint16 (*scan)[3], |
336 |
greg |
3.17 |
int len, double gv); |
337 |
greg |
3.15 |
/* |
338 |
|
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Convert 48-bit RGB scanline to encoded luminance and chrominance. |
339 |
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|
340 |
greg |
3.17 |
tms - tone mapping structure pointer. |
341 |
greg |
3.15 |
ls - returned encoded luminance values. |
342 |
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cs - returned encoded chrominance values (Note 2). |
343 |
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scan - input scanline. |
344 |
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len - scanline length. |
345 |
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gv - input gamma value. |
346 |
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|
347 |
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returns - 0 on success, TM_E_* on error. |
348 |
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*/ |
349 |
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|
350 |
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extern int |
351 |
greg |
3.17 |
tmCvGray16(TMstruct *tms, TMbright *ls, uint16 *scan, int len, double gv); |
352 |
greg |
3.15 |
/* |
353 |
|
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Convert 16-bit gray scanline to encoded luminance. |
354 |
|
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|
355 |
greg |
3.17 |
tms - tone mapping structure pointer. |
356 |
greg |
3.15 |
ls - returned encoded luminance values. |
357 |
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scan - input scanline. |
358 |
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len - scanline length. |
359 |
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gv - input gamma value. |
360 |
greg |
3.4 |
|
361 |
greg |
3.15 |
returns - 0 on success, TM_E_* on error. |
362 |
|
|
*/ |
363 |
greg |
3.4 |
|
364 |
greg |
3.1 |
/**** Notes ****/ |
365 |
|
|
/* |
366 |
|
|
General: |
367 |
|
|
|
368 |
|
|
The usual sequence after calling tmInit() is to convert some |
369 |
|
|
pixel values to chroma and luminance encodings, which can |
370 |
|
|
be passed to tmAddHisto() to put into the tone mapping histogram. |
371 |
|
|
This histogram is then used along with the display parameters |
372 |
greg |
3.5 |
by tmComputeMapping() to compute the luminance mapping function. |
373 |
greg |
3.1 |
(Colors are tone-mapped as they are converted if TM_F_MESOPIC |
374 |
|
|
is set.) The encoded chroma and luminance values may then be |
375 |
|
|
passed to tmMapPixels() to apply the computed tone mapping in |
376 |
|
|
a second pass. |
377 |
|
|
|
378 |
|
|
Especially for RGBE colors in the same color space as the |
379 |
|
|
target display, the conversion to chroma and luminance values |
380 |
|
|
is fast enough that it may be recomputed on the second pass |
381 |
|
|
if memory is at a premium. (Since the chroma values are only |
382 |
|
|
used during final mapping, setting the cs parameter to TM_NOCHROM |
383 |
|
|
on the first pass will save time.) Another memory saving option |
384 |
|
|
if third and subsequent passes are not needed is to use the |
385 |
greg |
3.3 |
same array to store the mapped pixels as used to store |
386 |
greg |
3.1 |
the encoded chroma values. This way, only two extra bytes |
387 |
|
|
for storing encoded luminances are required per pixel. This |
388 |
|
|
is the method employed by tmMapPicture(), for example. |
389 |
|
|
*/ |
390 |
|
|
/* |
391 |
|
|
Note 1: |
392 |
|
|
|
393 |
|
|
All RGBPRIMP values should be pointers to static structures. |
394 |
|
|
I.e., the same pointer should be used for the same primaries, |
395 |
|
|
and those primaries should not change from one call to the next. |
396 |
|
|
This is because the routines use the pointer value to identify |
397 |
|
|
computed conversion matrices, so the matrices do not have to be |
398 |
|
|
rebuilt each time. If you are using the standard primaries, |
399 |
|
|
use the standard primary pointer, stdprims. |
400 |
|
|
|
401 |
|
|
To indicate a set of input primaries are actually CIE XYZ, |
402 |
|
|
the TM_XYZPRIM macro may be passed. If the input primaries |
403 |
|
|
are unknown, it is wisest to pass tmTop->monpri to tmSetSpace(). |
404 |
|
|
By default, the input primaries equal the monitor primaries |
405 |
|
|
and the scalefactor is set to WHTEFFICACY in tmInit(). |
406 |
|
|
*/ |
407 |
|
|
/* |
408 |
|
|
Note 2: |
409 |
|
|
|
410 |
|
|
Chrominance is optional in most of these routines, whether |
411 |
|
|
TM_F_BW is set or not. Passing a value of TM_NOCHROM (or |
412 |
|
|
TM_NOCHROMP for picture reading) indicates that returned |
413 |
|
|
color values are not desired. |
414 |
|
|
|
415 |
|
|
If TM_NOCHROM is passed to a mapping routine expecting chroma |
416 |
|
|
input, it will do without it and return luminance channel |
417 |
|
|
rather than RGB pixel values. Otherwise, the array for |
418 |
|
|
returned pixel values may be the same array used to pass |
419 |
|
|
encoded chrominances if no other mappings are desired. |
420 |
|
|
*/ |
421 |
|
|
/* |
422 |
|
|
Note 3: |
423 |
|
|
|
424 |
|
|
Picture files may either be opened by the calling routine or by |
425 |
|
|
the library function. If opened by the calling routine, the |
426 |
|
|
pointer to the stream is passed, which may be a pipe or other |
427 |
|
|
non-seekable input as it is only read once. It must be |
428 |
|
|
positioned at the beginning when the function is called, and it |
429 |
|
|
will be positioned at the end on return. It will not be closed. |
430 |
|
|
If the passed stream pointer is TM_GETFILE, then the library |
431 |
|
|
function will open the file, read its contents and close it |
432 |
|
|
before returning, whether or not an error was encountered. |
433 |
|
|
*/ |
434 |
greg |
3.11 |
|
435 |
|
|
#ifdef __cplusplus |
436 |
|
|
} |
437 |
|
|
#endif |
438 |
schorsch |
3.13 |
#endif /* _RAD_TONEMAP_H_ */ |
439 |
|
|
|