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greg |
3.11 |
/* RCSid: $Id$ */ |
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greg |
3.1 |
/* |
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* Header file for tone mapping functions. |
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gwlarson |
3.8 |
* |
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* Include after "color.h" |
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greg |
3.1 |
*/ |
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greg |
3.11 |
/* ==================================================================== |
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* The Radiance Software License, Version 1.0 |
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* |
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* Copyright (c) 1990 - 2002 The Regents of the University of California, |
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* through Lawrence Berkeley National Laboratory. All rights reserved. |
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* |
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* Redistribution and use in source and binary forms, with or without |
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* modification, are permitted provided that the following conditions |
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* are met: |
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* |
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* 1. Redistributions of source code must retain the above copyright |
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* notice, this list of conditions and the following disclaimer. |
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* |
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* 2. Redistributions in binary form must reproduce the above copyright |
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* notice, this list of conditions and the following disclaimer in |
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* the documentation and/or other materials provided with the |
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* distribution. |
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* |
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* 3. The end-user documentation included with the redistribution, |
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* if any, must include the following acknowledgment: |
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* "This product includes Radiance software |
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* (http://radsite.lbl.gov/) |
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* developed by the Lawrence Berkeley National Laboratory |
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* (http://www.lbl.gov/)." |
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* Alternately, this acknowledgment may appear in the software itself, |
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* if and wherever such third-party acknowledgments normally appear. |
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* |
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* 4. The names "Radiance," "Lawrence Berkeley National Laboratory" |
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* and "The Regents of the University of California" must |
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* not be used to endorse or promote products derived from this |
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* software without prior written permission. For written |
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* permission, please contact [email protected]. |
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* |
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* 5. Products derived from this software may not be called "Radiance", |
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* nor may "Radiance" appear in their name, without prior written |
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* permission of Lawrence Berkeley National Laboratory. |
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* |
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* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED |
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* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
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* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
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* DISCLAIMED. IN NO EVENT SHALL Lawrence Berkeley National Laboratory OR |
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* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
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* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
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* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF |
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* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND |
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* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
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* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
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* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
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* SUCH DAMAGE. |
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* ==================================================================== |
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* |
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* This software consists of voluntary contributions made by many |
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* individuals on behalf of Lawrence Berkeley National Laboratory. For more |
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* information on Lawrence Berkeley National Laboratory, please see |
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* <http://www.lbl.gov/>. |
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*/ |
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#ifdef __cplusplus |
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extern "C" { |
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#endif |
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greg |
3.4 |
|
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greg |
3.1 |
/**** Argument Macros ****/ |
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/* Flags of what to do */ |
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#define TM_F_HCONTR 01 /* human contrast sensitivity */ |
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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 */ |
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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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/* special pointer values */ |
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#define TM_XYZPRIM (RGBPRIMP)NULL /* indicate XYZ primaries (Note 1) */ |
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#define TM_NOCHROM (BYTE *)NULL /* indicate no chrominance */ |
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#define TM_NOCHROMP (BYTE **)NULL /* indicate no chrominances */ |
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#define TM_GETFILE (FILE *)NULL /* indicate file must be opened */ |
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gwlarson |
3.8 |
|
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greg |
3.1 |
|
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/**** Error Return Values ****/ |
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#define TM_E_OK 0 /* normal return status */ |
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#define TM_E_NOMEM 1 /* out of memory */ |
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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 */ |
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greg |
3.4 |
#define TM_E_CODERR1 6 /* code consistency error 1 */ |
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#define TM_E_CODERR2 7 /* code consistency error 2 */ |
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greg |
3.1 |
|
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greg |
3.4 |
|
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greg |
3.1 |
/**** Conversion Constants and Table Sizes ****/ |
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#define TM_BRTSCALE 128 /* brightness scale factor (integer) */ |
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gwlarson |
3.10 |
#define TM_NOBRT (-1<<15) /* bogus brightness value */ |
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greg |
3.11 |
#define TM_NOLUM (1e-17) /* ridiculously small luminance */ |
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gwlarson |
3.10 |
|
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greg |
3.4 |
#define TM_MAXPKG 8 /* maximum number of color formats */ |
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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 */ |
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gregl |
3.6 |
extern int tmLastError; /* last error incurred by library */ |
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extern char *tmLastFunction; /* error-generating function name */ |
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greg |
3.1 |
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typedef short TMbright; /* encoded luminance type */ |
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/* basic tone mapping data structure */ |
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extern struct tmStruct { |
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int flags; /* flags of what to do */ |
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RGBPRIMP monpri; /* monitor RGB primaries */ |
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double mongam; /* monitor gamma value (approx.) */ |
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COLOR clf; /* computed luminance coefficients */ |
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greg |
3.4 |
int cdiv[3]; /* computed color divisors */ |
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greg |
3.1 |
RGBPRIMP inppri; /* current input primaries */ |
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double inpsf; /* current input scalefactor */ |
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COLORMAT cmat; /* color conversion matrix */ |
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gregl |
3.7 |
TMbright hbrmin, hbrmax; /* histogram brightness limits */ |
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greg |
3.1 |
int *histo; /* input histogram */ |
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gregl |
3.7 |
TMbright mbrmin, mbrmax; /* mapped brightness limits */ |
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greg |
3.1 |
unsigned short *lumap; /* computed luminance map */ |
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struct tmStruct *tmprev; /* previous tone mapping */ |
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greg |
3.4 |
MEM_PTR pd[TM_MAXPKG]; /* pointers to private data */ |
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greg |
3.1 |
} *tmTop; /* current tone mapping stack */ |
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greg |
3.4 |
|
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/* conversion package functions */ |
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#ifdef NOPROTO |
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struct tmPackage { |
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MEM_PTR (*Init)(); /* initialize private data */ |
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void (*NewSpace)(); /* new input color space (optional) */ |
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void (*Free)(); /* free private data */ |
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}; |
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#else |
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struct tmPackage { |
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MEM_PTR (*Init)(struct tmStruct *tms); |
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greg |
3.11 |
void (*NewSpace)(struct tmStruct *tms); |
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greg |
3.4 |
void (*Free)(MEM_PTR pp); |
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}; |
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#endif |
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/* our list of conversion packages */ |
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extern struct tmPackage *tmPkg[TM_MAXPKG]; |
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extern int tmNumPkgs; /* number of registered packages */ |
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greg |
3.1 |
/**** Useful Macros ****/ |
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greg |
3.4 |
/* compute luminance from encoded value */ |
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greg |
3.11 |
#define tmLuminance(li) exp((li)*(1./TM_BRTSCALE)) |
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greg |
3.1 |
|
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greg |
3.4 |
/* does tone mapping need color matrix? */ |
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#define tmNeedMatrix(t) ((t)->monpri != (t)->inppri) |
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/* register a conversion package */ |
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#define tmRegPkg(pf) ( tmNumPkgs >= TM_MAXPKG ? -1 : \ |
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(tmPkg[tmNumPkgs] = (pf), tmNumPkgs++) ) |
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/* get the specific package's data */ |
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#define tmPkgData(t,i) ((t)->pd[i]!=NULL ? (t)->pd[i] : (*tmPkg[i]->Init)(t)) |
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greg |
3.1 |
/**** Library Function Calls ****/ |
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greg |
3.4 |
#ifdef NOPROTO |
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greg |
3.1 |
|
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greg |
3.3 |
extern struct tmStruct *tmInit(), *tmPop(), *tmDup(); |
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greg |
3.11 |
extern int tmSetSpace(), tmPull(), tmPush(); |
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greg |
3.1 |
extern void tmClearHisto(), tmDone(); |
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greg |
3.11 |
extern int tmAddHisto(); |
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extern int tmFixedMapping(), tmComputeMapping(), tmMapPixels(); |
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extern int tmCvColors(), tmCvGrays(), tmCvColrs(); |
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extern int tmLoadPicture(), tmMapPicture(); |
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greg |
3.1 |
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#else |
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extern struct tmStruct * |
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tmInit(int flags, RGBPRIMP monpri, double gamval); |
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/* |
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Initialize new tone mapping and push it onto stack. |
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flags - TM_F_* flags indicating what is to be done. |
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monpri - display monitor primaries (Note 1). |
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gamval - display gamma response (can be approximate). |
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returns - new tmTop, or NULL if insufficient memory. |
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*/ |
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extern int |
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tmSetSpace(RGBPRIMP pri, double sf); |
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/* |
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Set color primaries and scale factor for incoming scanlines. |
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pri - RGB color input primaries (Note 1). |
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sf - scale factor to get to luminance in cd/m^2. |
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returns - 0 on success, TM_E_* code on failure. |
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*/ |
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extern void |
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tmClearHisto(void); |
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/* |
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Clear histogram for current tone mapping. |
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*/ |
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extern int |
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tmAddHisto(TMbright *ls, int len, int wt); |
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/* |
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Add brightness values to current histogram. |
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ls - encoded luminance values. |
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len - number of luminance values. |
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wt - integer weight to use for each value (usually 1 or -1). |
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returns - 0 on success, TM_E_* on error. |
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*/ |
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extern int |
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greg |
3.11 |
tmFixedMapping(double expmult, double gamval); |
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/* |
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Assign a fixed, linear tone-mapping using the given multiplier, |
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which is the ratio of maximum output to uncalibrated input. |
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This mapping will be used in subsequent calls to tmMapPixels() |
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until a new tone mapping is computed. |
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Only the min. and max. values are used from the histogram. |
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expmult - the fixed exposure multiplier to use. |
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gamval - display gamma response (0. for default). |
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returns - 0 on success, TM_E_* on error. |
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*/ |
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extern int |
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greg |
3.1 |
tmComputeMapping(double gamval, double Lddyn, double Ldmax); |
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/* |
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greg |
3.11 |
Compute tone mapping function from the current histogram. |
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This mapping will be used in subsequent calls to tmMapPixels() |
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until a new tone mapping is computed. |
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I.e., calls to tmAddHisto() have no immediate effect. |
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greg |
3.1 |
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gamval - display gamma response (0. for default). |
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Lddyn - the display's dynamic range (0. for default). |
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Ldmax - maximum display luminance in cd/m^2 (0. for default). |
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returns - 0 on success, TM_E_* on failure. |
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*/ |
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extern int |
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tmMapPixels(BYTE *ps, TMbright *ls, BYTE *cs, int len); |
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/* |
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Apply tone mapping function to pixel values. |
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ps - returned pixel values (Note 2). |
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ls - encoded luminance values. |
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cs - encoded chrominance values (Note 2). |
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len - number of pixels. |
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returns - 0 on success, TM_E_* on failure. |
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*/ |
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extern struct tmStruct * |
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tmPop(void); |
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/* |
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Pops current tone mapping from stack. |
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returns - pointer to tone mapping structure, or NULL if none. |
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*/ |
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extern int |
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tmPull(struct tmStruct *tms); |
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/* |
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Pull tone mapping from anywhere in stack. |
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tms - tone mapping structure to find. |
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returns - 1 if found in stack, 0 otherwise. |
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*/ |
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extern int |
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tmPush(struct tmStruct *tms); |
297 |
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/* |
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Make tone mapping active by (pulling it and) pushing it to the top. |
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300 |
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tms - initialized tone mapping structure. |
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returns - 0 on success, TM_E_* if tms is invalid. |
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*/ |
304 |
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305 |
greg |
3.3 |
extern struct tmStruct * |
306 |
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tmDup(void); |
307 |
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/* |
308 |
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Duplicate the current tone mapping into a new structure on the stack. |
309 |
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310 |
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returns - pointer to new top, or NULL on error. |
311 |
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*/ |
312 |
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313 |
greg |
3.1 |
extern void |
314 |
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tmDone(struct tmStruct *tms); |
315 |
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/* |
316 |
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Free data associated with the given tone mapping structure. |
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Calls tmPull() first to remove it from the stack if present. |
318 |
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The calls tmDone(tmPop()), tmDone(tmTop) and tmDone(NULL) |
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all have the same effect, which is to remove and free |
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the current tone mapping. |
321 |
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322 |
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tms - tone mapping structure to free. |
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*/ |
324 |
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325 |
greg |
3.11 |
extern int |
326 |
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tmCvColors(TMbright *ls, BYTE *cs, COLOR *scan, int len); |
327 |
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/* |
328 |
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Convert RGB/XYZ float scanline to encoded luminance and chrominance. |
329 |
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330 |
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ls - returned encoded luminance values. |
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cs - returned encoded chrominance values (Note 2). |
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scan - input scanline. |
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len - scanline length. |
334 |
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335 |
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returns - 0 on success, TM_E_* on error. |
336 |
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*/ |
337 |
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338 |
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extern int |
339 |
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tmCvGrays(TMbright *ls, float *scan, int len); |
340 |
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/* |
341 |
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Convert gray float scanline to encoded luminance. |
342 |
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343 |
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ls - returned encoded luminance values. |
344 |
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scan - input scanline. |
345 |
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len - scanline length. |
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 |
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tmCvColrs(TMbright *ls, BYTE *cs, COLR *scan, int len); |
352 |
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/* |
353 |
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Convert RGBE/XYZE scanline to encoded luminance and chrominance. |
354 |
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355 |
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ls - returned encoded luminance values. |
356 |
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cs - returned encoded chrominance values (Note 2). |
357 |
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scan - input scanline. |
358 |
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len - scanline length. |
359 |
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360 |
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returns - 0 on success, TM_E_* on error. |
361 |
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*/ |
362 |
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363 |
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extern int |
364 |
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tmLoadPicture(TMbright **lpp, BYTE **cpp, int *xp, int *yp, |
365 |
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char *fname, FILE *fp); |
366 |
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/* |
367 |
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Load Radiance picture and convert to tone mapping representation. |
368 |
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Memory for the luminance and chroma arrays is allocated using |
369 |
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malloc(3), and should be freed with free(3) when no longer needed. |
370 |
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Calls tmSetSpace() to calibrate input color space. |
371 |
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372 |
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lpp - returned array of encoded luminances, picture ordering. |
373 |
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cpp - returned array of encoded chrominances (Note 2). |
374 |
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xp, yp - returned picture dimensions. |
375 |
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fname - picture file name. |
376 |
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fp - pointer to open file (Note 3). |
377 |
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|
378 |
|
|
returns - 0 on success, TM_E_* on failure. |
379 |
|
|
*/ |
380 |
|
|
|
381 |
|
|
extern int |
382 |
|
|
tmMapPicture(BYTE **psp, int *xp, int *yp, int flags, |
383 |
|
|
RGBPRIMP monpri, double gamval, double Lddyn, double Ldmax, |
384 |
|
|
char *fname, FILE *fp); |
385 |
|
|
/* |
386 |
|
|
Load and apply tone mapping to Radiance picture. |
387 |
|
|
Stack is restored to its original state upon return. |
388 |
|
|
If fp is TM_GETFILE and (flags&TM_F_UNIMPL)!=0, tmMapPicture() |
389 |
|
|
calls pcond to perform the actual conversion, which takes |
390 |
|
|
longer but gives access to all the TM_F_* features. |
391 |
|
|
Memory for the final pixel array is allocated using malloc(3), |
392 |
|
|
and should be freed with free(3) when it is no longer needed. |
393 |
|
|
|
394 |
|
|
psp - returned array of tone mapped pixels, picture ordering. |
395 |
|
|
xp, yp - returned picture dimensions. |
396 |
|
|
flags - TM_F_* flags indicating what is to be done. |
397 |
|
|
monpri - display monitor primaries (Note 1). |
398 |
|
|
gamval - display gamma response. |
399 |
|
|
Lddyn - the display's dynamic range (0. for default). |
400 |
|
|
Ldmax - maximum display luminance in cd/m^2 (0. for default). |
401 |
|
|
fname - picture file name. |
402 |
|
|
fp - pointer to open file (Note 3). |
403 |
|
|
|
404 |
|
|
returns - 0 on success, TM_E_* on failure. |
405 |
|
|
*/ |
406 |
|
|
|
407 |
greg |
3.1 |
#endif |
408 |
greg |
3.4 |
|
409 |
|
|
|
410 |
greg |
3.1 |
/**** Notes ****/ |
411 |
|
|
/* |
412 |
|
|
General: |
413 |
|
|
|
414 |
|
|
The usual sequence after calling tmInit() is to convert some |
415 |
|
|
pixel values to chroma and luminance encodings, which can |
416 |
|
|
be passed to tmAddHisto() to put into the tone mapping histogram. |
417 |
|
|
This histogram is then used along with the display parameters |
418 |
greg |
3.5 |
by tmComputeMapping() to compute the luminance mapping function. |
419 |
greg |
3.1 |
(Colors are tone-mapped as they are converted if TM_F_MESOPIC |
420 |
|
|
is set.) The encoded chroma and luminance values may then be |
421 |
|
|
passed to tmMapPixels() to apply the computed tone mapping in |
422 |
|
|
a second pass. |
423 |
|
|
|
424 |
|
|
Especially for RGBE colors in the same color space as the |
425 |
|
|
target display, the conversion to chroma and luminance values |
426 |
|
|
is fast enough that it may be recomputed on the second pass |
427 |
|
|
if memory is at a premium. (Since the chroma values are only |
428 |
|
|
used during final mapping, setting the cs parameter to TM_NOCHROM |
429 |
|
|
on the first pass will save time.) Another memory saving option |
430 |
|
|
if third and subsequent passes are not needed is to use the |
431 |
greg |
3.3 |
same array to store the mapped pixels as used to store |
432 |
greg |
3.1 |
the encoded chroma values. This way, only two extra bytes |
433 |
|
|
for storing encoded luminances are required per pixel. This |
434 |
|
|
is the method employed by tmMapPicture(), for example. |
435 |
|
|
*/ |
436 |
|
|
/* |
437 |
|
|
Note 1: |
438 |
|
|
|
439 |
|
|
All RGBPRIMP values should be pointers to static structures. |
440 |
|
|
I.e., the same pointer should be used for the same primaries, |
441 |
|
|
and those primaries should not change from one call to the next. |
442 |
|
|
This is because the routines use the pointer value to identify |
443 |
|
|
computed conversion matrices, so the matrices do not have to be |
444 |
|
|
rebuilt each time. If you are using the standard primaries, |
445 |
|
|
use the standard primary pointer, stdprims. |
446 |
|
|
|
447 |
|
|
To indicate a set of input primaries are actually CIE XYZ, |
448 |
|
|
the TM_XYZPRIM macro may be passed. If the input primaries |
449 |
|
|
are unknown, it is wisest to pass tmTop->monpri to tmSetSpace(). |
450 |
|
|
By default, the input primaries equal the monitor primaries |
451 |
|
|
and the scalefactor is set to WHTEFFICACY in tmInit(). |
452 |
|
|
*/ |
453 |
|
|
/* |
454 |
|
|
Note 2: |
455 |
|
|
|
456 |
|
|
Chrominance is optional in most of these routines, whether |
457 |
|
|
TM_F_BW is set or not. Passing a value of TM_NOCHROM (or |
458 |
|
|
TM_NOCHROMP for picture reading) indicates that returned |
459 |
|
|
color values are not desired. |
460 |
|
|
|
461 |
|
|
If TM_NOCHROM is passed to a mapping routine expecting chroma |
462 |
|
|
input, it will do without it and return luminance channel |
463 |
|
|
rather than RGB pixel values. Otherwise, the array for |
464 |
|
|
returned pixel values may be the same array used to pass |
465 |
|
|
encoded chrominances if no other mappings are desired. |
466 |
|
|
*/ |
467 |
|
|
/* |
468 |
|
|
Note 3: |
469 |
|
|
|
470 |
|
|
Picture files may either be opened by the calling routine or by |
471 |
|
|
the library function. If opened by the calling routine, the |
472 |
|
|
pointer to the stream is passed, which may be a pipe or other |
473 |
|
|
non-seekable input as it is only read once. It must be |
474 |
|
|
positioned at the beginning when the function is called, and it |
475 |
|
|
will be positioned at the end on return. It will not be closed. |
476 |
|
|
If the passed stream pointer is TM_GETFILE, then the library |
477 |
|
|
function will open the file, read its contents and close it |
478 |
|
|
before returning, whether or not an error was encountered. |
479 |
|
|
*/ |
480 |
greg |
3.11 |
|
481 |
|
|
#ifdef __cplusplus |
482 |
|
|
} |
483 |
|
|
#endif |