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/* RCSid $Id: tonemap.h,v 3.27 2021/01/06 19:25:00 greg Exp $ */ | 
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/* | 
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 * Header file for tone mapping functions. | 
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 * | 
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 * Include after "color.h" | 
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 */ | 
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#ifndef _RAD_TONEMAP_H_ | 
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#define _RAD_TONEMAP_H_ | 
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 | 
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#include        "tiff.h"        /* needed for int32, etc. */ | 
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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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 | 
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/****    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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#define TM_F_NOSTDERR   0400            /* don't report errors to stderr */ | 
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                                /* 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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 | 
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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      (uby8 *)NULL    /* indicate no chrominance */ | 
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#define TM_NOCHROMP     (uby8 **)NULL   /* indicate no chrominances */ | 
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#define TM_GETFILE      (FILE *)NULL    /* indicate file must be opened */ | 
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 | 
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 | 
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/****    Error Return Values    ****/ | 
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 | 
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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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#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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 | 
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 | 
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/****    Conversion Constants and Table Sizes    ****/ | 
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 | 
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#define TM_BRTSCALE     256             /* brightness scale factor (integer) */ | 
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 | 
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#define TM_NOBRT        (~0x7fff)       /* bogus brightness value */ | 
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#define TM_NOLUM        (1e-17)         /* ridiculously small luminance */ | 
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 | 
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#define TM_BRES         4096            /* luminance tone-map resolution */ | 
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 | 
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#define TM_MAXPKG       8               /* maximum number of color formats */ | 
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 | 
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 | 
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/****    Global Data Types and Structures    ****/ | 
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 | 
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#ifndef MEM_PTR | 
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#define MEM_PTR         void * | 
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#endif | 
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#ifndef HIST_TYP | 
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#define HIST_TYP        unsigned long | 
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#endif | 
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#define TMAP_TYP        unsigned short | 
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 | 
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extern char     *tmErrorMessage[];      /* error messages */ | 
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 | 
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typedef short   TMbright;               /* encoded luminance type */ | 
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 | 
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                                /* basic tone mapping data structure */ | 
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typedef struct { | 
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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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        int             cdiv[3];        /* computed color divisors */ | 
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        RGBPRIMP        inppri;         /* current input primaries */ | 
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        double          inpsf;          /* current input scalefactor */ | 
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        MEM_PTR         inpdat;         /* current input client data */ | 
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        COLORMAT        cmat;           /* color conversion matrix */ | 
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        TMbright        hbrmin, hbrmax; /* histogram brightness limits */        | 
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        HIST_TYP        *histo;         /* input histogram */ | 
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        TMbright        mbrmin, mbrmax; /* mapped brightness limits */ | 
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        TMAP_TYP        *lumap;         /* computed luminance map */ | 
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        MEM_PTR         pd[TM_MAXPKG];  /* pointers to private data */ | 
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        int             lastError;      /* last error incurred */ | 
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        const char      *lastFunc;      /* error-generating function name */ | 
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} TMstruct; | 
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 | 
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                                /* conversion package functions */ | 
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struct tmPackage { | 
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        MEM_PTR         (*Init)(TMstruct *tms); | 
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        void            (*NewSpace)(TMstruct *tms); | 
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        void            (*Free)(MEM_PTR pp); | 
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}; | 
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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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 | 
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 | 
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/****    Useful Macros    ****/ | 
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 | 
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                                /* compute luminance from encoded value */ | 
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#define tmLuminance(li) exp((li)*(1./TM_BRTSCALE)) | 
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 | 
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                                /* does tone mapping need color matrix? */ | 
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#define tmNeedMatrix(t) ((t)->monpri != (t)->inppri) | 
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 | 
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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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 | 
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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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 | 
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 | 
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/****    Library Function Calls    ****/ | 
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 | 
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extern TMbright | 
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tmCvLuminance(double lum); | 
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/* | 
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        Convert a single luminance value to an encoded brightness value. | 
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 */ | 
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 | 
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extern int | 
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tmCvLums(TMbright *ls, float *scan, int len); | 
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/* | 
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        Convert luminance values to encoded brightness values using lookup. | 
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 | 
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        ls      -       returned encoded luminance values. | 
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        scan    -       input scanline. | 
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        len     -       scanline length. | 
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 | 
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        returns -       0 on success, TM_E_* on error. | 
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 */ | 
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 | 
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extern TMstruct * | 
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tmInit(int flags, RGBPRIMP monpri, double gamval); | 
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/* | 
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        Allocate and initialize new tone mapping. | 
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 | 
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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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 | 
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        returns -       new tone-mapping pointer, or NULL if no memory. | 
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*/ | 
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 | 
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extern int | 
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tmSetSpace(TMstruct *tms, RGBPRIMP pri, double sf, MEM_PTR dat); | 
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/* | 
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        Set color primaries and scale factor for incoming scanlines. | 
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 | 
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        tms     -       tone mapping structure pointer. | 
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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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        dat     -       application-specific data (NULL if not needed) | 
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 | 
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        returns -       0 on success, TM_E_* code on failure. | 
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*/ | 
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 | 
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extern void | 
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tmClearHisto(TMstruct *tms); | 
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/* | 
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        Clear histogram for current tone mapping. | 
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 | 
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        tms     -       tone mapping structure pointer. | 
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*/ | 
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 | 
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extern int | 
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tmAddHisto(TMstruct *tms, TMbright *ls, int len, int wt); | 
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/* | 
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        Add brightness values to current histogram. | 
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 | 
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        tms     -       tone mapping structure pointer. | 
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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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 | 
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        returns -       0 on success, TM_E_* on error. | 
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*/ | 
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 | 
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extern int | 
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tmFixedMapping(TMstruct *tms, 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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         | 
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        tms     -       tone mapping structure pointer. | 
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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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 | 
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        returns -       0 on success, TM_E_* on error. | 
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*/ | 
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 | 
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extern int | 
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tmComputeMapping(TMstruct *tms, double gamval, double Lddyn, double Ldmax); | 
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/* | 
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        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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 | 
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        tms     -       tone mapping structure pointer. | 
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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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 | 
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        returns -       0 on success, TM_E_* on failure. | 
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*/ | 
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 | 
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extern int | 
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tmMapPixels(TMstruct *tms, uby8 *ps, TMbright *ls, uby8 *cs, int len); | 
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/* | 
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        Apply tone mapping function to pixel values. | 
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 | 
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        tms     -       tone mapping structure pointer. | 
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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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 | 
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        returns -       0 on success, TM_E_* on failure. | 
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*/ | 
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 | 
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extern TMstruct * | 
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tmDup(TMstruct *orig); | 
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/* | 
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        Duplicate the given tone mapping into a new struct. | 
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 | 
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        orig    -       tone mapping structure to duplicate. | 
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 | 
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        returns -       pointer to new struct, or NULL on error. | 
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*/ | 
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 | 
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extern void | 
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tmDone(TMstruct *tms); | 
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/* | 
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        Free data associated with the given tone mapping structure. | 
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 | 
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        tms     -       tone mapping structure to free. | 
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*/ | 
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 | 
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extern int | 
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tmCvGrays(TMstruct *tms, TMbright *ls, float *scan, int len); | 
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/* | 
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        Convert gray float scanline to encoded luminance. | 
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 | 
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        tms     -       tone mapping structure pointer. | 
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        ls      -       returned encoded luminance values. | 
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        scan    -       input scanline. | 
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        len     -       scanline length. | 
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 | 
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        returns -       0 on success, TM_E_* on error. | 
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*/ | 
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 | 
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extern int | 
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tmCvColors(TMstruct *tms, TMbright *ls, uby8 *cs, COLOR *scan, int len); | 
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/* | 
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        Convert RGB/XYZ float scanline to encoded luminance and chrominance. | 
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 | 
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        tms     -       tone mapping structure pointer. | 
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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. | 
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 | 
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        returns -       0 on success, TM_E_* on error. | 
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*/ | 
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 | 
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extern int | 
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tmCvColrs(TMstruct *tms, TMbright *ls, uby8 *cs, COLR *scan, int len); | 
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/* | 
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        Convert RGBE/XYZE scanline to encoded luminance and chrominance. | 
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 | 
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        tms     -       tone mapping structure pointer. | 
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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. | 
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 | 
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        returns -       0 on success, TM_E_* on error. | 
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*/ | 
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 | 
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extern int | 
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tmLoadPicture(TMstruct *tms, TMbright **lpp, uby8 **cpp, int *xp, int *yp, | 
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                char *fname, FILE *fp); | 
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/* | 
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        Load Radiance picture and convert to tone mapping representation. | 
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        Memory for the luminance and chroma arrays is allocated using | 
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        malloc(3), and should be freed with free(3) when no longer needed. | 
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        Calls tmSetSpace() to calibrate input color space. | 
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 | 
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        tms     -       tone mapping structure pointer. | 
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        lpp     -       returned array of encoded luminances, picture ordering. | 
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        cpp     -       returned array of encoded chrominances (Note 2). | 
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        xp, yp  -       returned picture dimensions. | 
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        fname   -       picture file name. | 
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        fp      -       pointer to open file (Note 3). | 
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 | 
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        returns -       0 on success, TM_E_* on failure. | 
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*/ | 
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 | 
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extern int | 
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tmMapPicture(uby8 **psp, int *xp, int *yp, int flags, | 
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                RGBPRIMP monpri, double gamval, double Lddyn, double Ldmax, | 
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                char *fname, FILE *fp); | 
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/* | 
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        Load and apply tone mapping to Radiance picture. | 
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        If fp is TM_GETFILE and (flags&TM_F_UNIMPL)!=0, tmMapPicture() | 
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        calls pcond to perform the actual conversion, which takes | 
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        longer but gives access to all the TM_F_* features. | 
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        Memory for the final pixel array is allocated using malloc(3), | 
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        and should be freed with free(3) when it is no longer needed. | 
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 | 
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        psp     -       returned array of tone mapped pixels, picture ordering. | 
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        xp, yp  -       returned picture dimensions. | 
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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. | 
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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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        fname   -       picture file name. | 
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        fp      -       pointer to open file (Note 3). | 
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 | 
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        returns -       0 on success, TM_E_* on failure. | 
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*/ | 
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 | 
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extern int | 
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tmCvRGB48(TMstruct *tms, TMbright *ls, uby8 *cs, uint16 (*scan)[3], | 
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                int len, double gv); | 
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/* | 
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        Convert 48-bit RGB scanline to encoded luminance and chrominance. | 
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 | 
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        tms     -       tone mapping structure pointer. | 
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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. | 
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        gv      -       input gamma value. | 
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 | 
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        returns -       0 on success, TM_E_* on error. | 
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*/ | 
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 | 
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extern int | 
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tmCvGray16(TMstruct *tms, TMbright *ls, uint16 *scan, int len, double gv); | 
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/* | 
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        Convert 16-bit gray scanline to encoded luminance. | 
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 | 
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        tms     -       tone mapping structure pointer. | 
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        ls      -       returned encoded luminance values. | 
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        scan    -       input scanline. | 
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        len     -       scanline length. | 
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        gv      -       input gamma value. | 
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 | 
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        returns -       0 on success, TM_E_* on error. | 
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*/ | 
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 | 
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/****    Notes    ****/ | 
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/* | 
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        General: | 
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 | 
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        The usual sequence after calling tmInit() is to convert some | 
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        pixel values to chroma and luminance encodings, which can | 
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        be passed to tmAddHisto() to put into the tone mapping histogram. | 
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        This histogram is then used along with the display parameters | 
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        by tmComputeMapping() to compute the luminance mapping function. | 
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        (Colors are tone-mapped as they are converted if TM_F_MESOPIC | 
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        is set.)  The encoded chroma and luminance values may then be | 
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        passed to tmMapPixels() to apply the computed tone mapping in | 
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        a second pass. | 
| 383 | 
 | 
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        Especially for RGBE colors in the same color space as the | 
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        target display, the conversion to chroma and luminance values | 
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        is fast enough that it may be recomputed on the second pass | 
| 387 | 
        if memory is at a premium.  (Since the chroma values are only | 
| 388 | 
        used during final mapping, setting the cs parameter to TM_NOCHROM | 
| 389 | 
        on the first pass will save time.)  Another memory saving option | 
| 390 | 
        if third and subsequent passes are not needed is to use the | 
| 391 | 
        same array to store the mapped pixels as used to store | 
| 392 | 
        the encoded chroma values.  This way, only two extra bytes | 
| 393 | 
        for storing encoded luminances are required per pixel.  This | 
| 394 | 
        is the method employed by tmMapPicture(), for example. | 
| 395 | 
*/ | 
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/* | 
| 397 | 
        Note 1: | 
| 398 | 
 | 
| 399 | 
        All RGBPRIMP values should be pointers to static structures. | 
| 400 | 
        I.e., the same pointer should be used for the same primaries, | 
| 401 | 
        and those primaries should not change from one call to the next. | 
| 402 | 
        This is because the routines use the pointer value to identify | 
| 403 | 
        computed conversion matrices, so the matrices do not have to be | 
| 404 | 
        rebuilt each time.  If you are using the standard primaries, | 
| 405 | 
        use the standard primary pointer, stdprims. | 
| 406 | 
 | 
| 407 | 
        To indicate a set of input primaries are actually CIE XYZ, | 
| 408 | 
        the TM_XYZPRIM macro may be passed.  If the input primaries | 
| 409 | 
        are unknown, it is wisest to pass tmTop->monpri to tmSetSpace(). | 
| 410 | 
        By default, the input primaries equal the monitor primaries | 
| 411 | 
        and the scalefactor is set to WHTEFFICACY in tmInit(). | 
| 412 | 
*/ | 
| 413 | 
/* | 
| 414 | 
        Note 2: | 
| 415 | 
 | 
| 416 | 
        Chrominance is optional in most of these routines, whether | 
| 417 | 
        TM_F_BW is set or not.  Passing a value of TM_NOCHROM (or | 
| 418 | 
        TM_NOCHROMP for picture reading) indicates that returned | 
| 419 | 
        color values are not desired. | 
| 420 | 
         | 
| 421 | 
        If TM_NOCHROM is passed to a mapping routine expecting chroma | 
| 422 | 
        input, it will do without it and return luminance channel | 
| 423 | 
        rather than RGB pixel values.  Otherwise, the array for | 
| 424 | 
        returned pixel values may be the same array used to pass | 
| 425 | 
        encoded chrominances if no other mappings are desired. | 
| 426 | 
*/ | 
| 427 | 
/* | 
| 428 | 
        Note 3: | 
| 429 | 
 | 
| 430 | 
        Picture files may either be opened by the calling routine or by | 
| 431 | 
        the library function.  If opened by the calling routine, the | 
| 432 | 
        pointer to the stream is passed, which may be a pipe or other | 
| 433 | 
        non-seekable input as it is only read once.  It must be | 
| 434 | 
        positioned at the beginning when the function is called, and it | 
| 435 | 
        will be positioned at the end on return.  It will not be closed. | 
| 436 | 
        If the passed stream pointer is TM_GETFILE, then the library | 
| 437 | 
        function will open the file, read its contents and close it | 
| 438 | 
        before returning, whether or not an error was encountered. | 
| 439 | 
*/ | 
| 440 | 
 | 
| 441 | 
#ifdef __cplusplus | 
| 442 | 
} | 
| 443 | 
#endif | 
| 444 | 
#endif /* _RAD_TONEMAP_H_ */ | 
| 445 | 
 |