src/common/tonemap.h

/* RCSid $Id: tonemap.h,v 3.14 2003/06/27 06:53:22 greg Exp $ */
/*
 * Header file for tone mapping functions.
 *
 * Include after "color.h"
 */
#ifndef _RAD_TONEMAP_H_
#define _RAD_TONEMAP_H_
#ifdef __cplusplus
extern "C" {
#endif

#include        "tifftypes.h"

/****    Argument Macros    ****/
                                /* Flags of what to do */
#define TM_F_HCONTR     01              /* human contrast sensitivity */
#define TM_F_MESOPIC    02              /* mesopic color sensitivity */
#define TM_F_LINEAR     04              /* linear brightness mapping */
#define TM_F_ACUITY     010             /* acuity adjustment */
#define TM_F_VEIL       020             /* veiling glare */
#define TM_F_CWEIGHT    040             /* center weighting */
#define TM_F_FOVEAL     0100            /* use foveal sample size */
#define TM_F_BW         0200            /* luminance only */
#define TM_F_NOSTDERR   0400            /* don't report errors to stderr */
                                /* combined modes */
#define TM_F_CAMERA     0
#define TM_F_HUMAN      (TM_F_HCONTR|TM_F_MESOPIC|TM_F_VEIL|\
                                TM_F_ACUITY|TM_F_FOVEAL)
#define TM_F_UNIMPL     (TM_F_CWEIGHT|TM_F_VEIL|TM_F_ACUITY|TM_F_FOVEAL)

                                /* special pointer values */
#define TM_XYZPRIM      (RGBPRIMP)NULL  /* indicate XYZ primaries (Note 1) */
#define TM_NOCHROM      (BYTE *)NULL    /* indicate no chrominance */
#define TM_NOCHROMP     (BYTE **)NULL   /* indicate no chrominances */
#define TM_GETFILE      (FILE *)NULL    /* indicate file must be opened */


/****    Error Return Values    ****/

#define TM_E_OK         0               /* normal return status */
#define TM_E_NOMEM      1               /* out of memory */
#define TM_E_ILLEGAL    2               /* illegal argument value */
#define TM_E_TMINVAL    3               /* no valid tone mapping */
#define TM_E_TMFAIL     4               /* cannot compute tone mapping */
#define TM_E_BADFILE    5               /* cannot open or understand file */
#define TM_E_CODERR1    6               /* code consistency error 1 */
#define TM_E_CODERR2    7               /* code consistency error 2 */


/****    Conversion Constants and Table Sizes    ****/

#define TM_BRTSCALE     128             /* brightness scale factor (integer) */

#define TM_NOBRT        (-1<<15)        /* bogus brightness value */
#define TM_NOLUM        (1e-17)         /* ridiculously small luminance */

#define TM_MAXPKG       8               /* maximum number of color formats */


/****    Global Data Types and Structures    ****/

#ifndef MEM_PTR
#define MEM_PTR         void *
#endif

extern char     *tmErrorMessage[];      /* error messages */
extern int      tmLastError;            /* last error incurred by library */
extern char     *tmLastFunction;        /* error-generating function name */

typedef short   TMbright;               /* encoded luminance type */

                                /* basic tone mapping data structure */
extern struct tmStruct {
        int             flags;          /* flags of what to do */
        RGBPRIMP        monpri;         /* monitor RGB primaries */
        double          mongam;         /* monitor gamma value (approx.) */
        COLOR           clf;            /* computed luminance coefficients */
        int             cdiv[3];        /* computed color divisors */
        RGBPRIMP        inppri;         /* current input primaries */
        double          inpsf;          /* current input scalefactor */
        COLORMAT        cmat;           /* color conversion matrix */
        TMbright        hbrmin, hbrmax; /* histogram brightness limits */       
        int             *histo;         /* input histogram */
        TMbright        mbrmin, mbrmax; /* mapped brightness limits */
        unsigned short  *lumap;         /* computed luminance map */
        struct tmStruct *tmprev;        /* previous tone mapping */
        MEM_PTR         pd[TM_MAXPKG];  /* pointers to private data */
}       *tmTop;                 /* current tone mapping stack */

                                /* conversion package functions */
struct tmPackage {
        MEM_PTR         (*Init)(struct tmStruct *tms);
        void            (*NewSpace)(struct tmStruct *tms);
        void            (*Free)(MEM_PTR pp);
};
                                /* our list of conversion packages */
extern struct tmPackage *tmPkg[TM_MAXPKG];
extern int      tmNumPkgs;      /* number of registered packages */


/****    Useful Macros    ****/

                                /* compute luminance from encoded value */
#define tmLuminance(li) exp((li)*(1./TM_BRTSCALE))

                                /* does tone mapping need color matrix? */
#define tmNeedMatrix(t) ((t)->monpri != (t)->inppri)

                                /* register a conversion package */
#define tmRegPkg(pf)    ( tmNumPkgs >= TM_MAXPKG ? -1 : \
                                (tmPkg[tmNumPkgs] = (pf), tmNumPkgs++) )

                                /* get the specific package's data */
#define tmPkgData(t,i)  ((t)->pd[i]!=NULL ? (t)->pd[i] : (*tmPkg[i]->Init)(t))


/****    Library Function Calls    ****/


extern struct tmStruct *
tmInit(int flags, RGBPRIMP monpri, double gamval);
/*
        Initialize new tone mapping and push it onto stack.

        flags   -       TM_F_* flags indicating what is to be done.
        monpri  -       display monitor primaries (Note 1).
        gamval  -       display gamma response (can be approximate).

        returns -       new tmTop, or NULL if insufficient memory.
*/

extern int
tmSetSpace(RGBPRIMP pri, double sf);
/*
        Set color primaries and scale factor for incoming scanlines.

        pri     -       RGB color input primaries (Note 1).
        sf      -       scale factor to get to luminance in cd/m^2.

        returns -       0 on success, TM_E_* code on failure.
*/

extern void
tmClearHisto(void);
/*
        Clear histogram for current tone mapping.
*/

extern int
tmAddHisto(TMbright *ls, int len, int wt);
/*
        Add brightness values to current histogram.

        ls      -       encoded luminance values.
        len     -       number of luminance values.
        wt      -       integer weight to use for each value (usually 1 or -1).

        returns -       0 on success, TM_E_* on error.
*/

extern int
tmFixedMapping(double expmult, double gamval);
/*
        Assign a fixed, linear tone-mapping using the given multiplier,
        which is the ratio of maximum output to uncalibrated input.
        This mapping will be used in subsequent calls to tmMapPixels()
        until a new tone mapping is computed.
        Only the min. and max. values are used from the histogram.
        
        expmult -       the fixed exposure multiplier to use.
        gamval  -       display gamma response (0. for default).
        returns -       0 on success, TM_E_* on error.
*/

extern int
tmComputeMapping(double gamval, double Lddyn, double Ldmax);
/*
        Compute tone mapping function from the current histogram.
        This mapping will be used in subsequent calls to tmMapPixels()
        until a new tone mapping is computed.
        I.e., calls to tmAddHisto() have no immediate effect.

        gamval  -       display gamma response (0. for default).
        Lddyn   -       the display's dynamic range (0. for default).
        Ldmax   -       maximum display luminance in cd/m^2 (0. for default).

        returns -       0 on success, TM_E_* on failure.
*/

extern int
tmMapPixels(BYTE *ps, TMbright *ls, BYTE *cs, int len);
/*
        Apply tone mapping function to pixel values.

        ps      -       returned pixel values (Note 2).
        ls      -       encoded luminance values.
        cs      -       encoded chrominance values (Note 2).
        len     -       number of pixels.

        returns -       0 on success, TM_E_* on failure.
*/

extern struct tmStruct *
tmPop(void);
/*
        Pops current tone mapping from stack.

        returns -       pointer to tone mapping structure, or NULL if none.
*/

extern int
tmPull(struct tmStruct *tms);
/*
        Pull tone mapping from anywhere in stack.

        tms     -       tone mapping structure to find.

        returns -       1 if found in stack, 0 otherwise.
*/

extern int
tmPush(struct tmStruct *tms);
/*
        Make tone mapping active by (pulling it and) pushing it to the top.

        tms     -       initialized tone mapping structure.

        returns -       0 on success, TM_E_* if tms is invalid.
*/

extern struct tmStruct *
tmDup(void);
/*
        Duplicate the current tone mapping into a new structure on the stack.

        returns -       pointer to new top, or NULL on error.
*/

extern void
tmDone(struct tmStruct *tms);
/*
        Free data associated with the given tone mapping structure.
        Calls tmPull() first to remove it from the stack if present.
        The calls tmDone(tmPop()), tmDone(tmTop) and tmDone(NULL)
        all have the same effect, which is to remove and free
        the current tone mapping.

        tms     -       tone mapping structure to free.
*/

extern int
tmCvColors(TMbright *ls, BYTE *cs, COLOR *scan, int len);
/*
        Convert RGB/XYZ float scanline to encoded luminance and chrominance.

        ls      -       returned encoded luminance values.
        cs      -       returned encoded chrominance values (Note 2).
        scan    -       input scanline.
        len     -       scanline length.

        returns -       0 on success, TM_E_* on error.
*/

extern int
tmCvGrays(TMbright *ls, float *scan, int len);
/*
        Convert gray float scanline to encoded luminance.

        ls      -       returned encoded luminance values.
        scan    -       input scanline.
        len     -       scanline length.

        returns -       0 on success, TM_E_* on error.
*/

extern int
tmCvColrs(TMbright *ls, BYTE *cs, COLR *scan, int len);
/*
        Convert RGBE/XYZE scanline to encoded luminance and chrominance.

        ls      -       returned encoded luminance values.
        cs      -       returned encoded chrominance values (Note 2).
        scan    -       input scanline.
        len     -       scanline length.

        returns -       0 on success, TM_E_* on error.
*/

extern int
tmLoadPicture(TMbright **lpp, BYTE **cpp, int *xp, int *yp,
                char *fname, FILE *fp);
/*
        Load Radiance picture and convert to tone mapping representation.
        Memory for the luminance and chroma arrays is allocated using
        malloc(3), and should be freed with free(3) when no longer needed.
        Calls tmSetSpace() to calibrate input color space.

        lpp     -       returned array of encoded luminances, picture ordering.
        cpp     -       returned array of encoded chrominances (Note 2).
        xp, yp  -       returned picture dimensions.
        fname   -       picture file name.
        fp      -       pointer to open file (Note 3).

        returns -       0 on success, TM_E_* on failure.
*/

extern int
tmMapPicture(BYTE **psp, int *xp, int *yp, int flags,
                RGBPRIMP monpri, double gamval, double Lddyn, double Ldmax,
                char *fname, FILE *fp);
/*
        Load and apply tone mapping to Radiance picture.
        Stack is restored to its original state upon return.
        If fp is TM_GETFILE and (flags&TM_F_UNIMPL)!=0, tmMapPicture()
        calls pcond to perform the actual conversion, which takes
        longer but gives access to all the TM_F_* features.
        Memory for the final pixel array is allocated using malloc(3),
        and should be freed with free(3) when it is no longer needed.

        psp     -       returned array of tone mapped pixels, picture ordering.
        xp, yp  -       returned picture dimensions.
        flags   -       TM_F_* flags indicating what is to be done.
        monpri  -       display monitor primaries (Note 1).
        gamval  -       display gamma response.
        Lddyn   -       the display's dynamic range (0. for default).
        Ldmax   -       maximum display luminance in cd/m^2 (0. for default).
        fname   -       picture file name.
        fp      -       pointer to open file (Note 3).

        returns -       0 on success, TM_E_* on failure.
*/

extern int
tmCvRGB48(TMbright *ls, BYTE *cs, uint16 (*scan)[3], int len, double gv);
/*
        Convert 48-bit RGB scanline to encoded luminance and chrominance.

        ls      -       returned encoded luminance values.
        cs      -       returned encoded chrominance values (Note 2).
        scan    -       input scanline.
        len     -       scanline length.
        gv      -       input gamma value.

        returns -       0 on success, TM_E_* on error.
*/

extern int
tmCvGray16(TMbright *ls, uint16 *scan, int len, double gv);
/*
        Convert 16-bit gray scanline to encoded luminance.

        ls      -       returned encoded luminance values.
        scan    -       input scanline.
        len     -       scanline length.
        gv      -       input gamma value.

        returns -       0 on success, TM_E_* on error.
*/

/****    Notes    ****/
/*
        General:

        The usual sequence after calling tmInit() is to convert some
        pixel values to chroma and luminance encodings, which can
        be passed to tmAddHisto() to put into the tone mapping histogram.
        This histogram is then used along with the display parameters
        by tmComputeMapping() to compute the luminance mapping function.
        (Colors are tone-mapped as they are converted if TM_F_MESOPIC
        is set.)  The encoded chroma and luminance values may then be
        passed to tmMapPixels() to apply the computed tone mapping in
        a second pass.

        Especially for RGBE colors in the same color space as the
        target display, the conversion to chroma and luminance values
        is fast enough that it may be recomputed on the second pass
        if memory is at a premium.  (Since the chroma values are only
        used during final mapping, setting the cs parameter to TM_NOCHROM
        on the first pass will save time.)  Another memory saving option
        if third and subsequent passes are not needed is to use the
        same array to store the mapped pixels as used to store
        the encoded chroma values.  This way, only two extra bytes
        for storing encoded luminances are required per pixel.  This
        is the method employed by tmMapPicture(), for example.
*/
/*
        Note 1:

        All RGBPRIMP values should be pointers to static structures.
        I.e., the same pointer should be used for the same primaries,
        and those primaries should not change from one call to the next.
        This is because the routines use the pointer value to identify
        computed conversion matrices, so the matrices do not have to be
        rebuilt each time.  If you are using the standard primaries,
        use the standard primary pointer, stdprims.

        To indicate a set of input primaries are actually CIE XYZ,
        the TM_XYZPRIM macro may be passed.  If the input primaries
        are unknown, it is wisest to pass tmTop->monpri to tmSetSpace().
        By default, the input primaries equal the monitor primaries
        and the scalefactor is set to WHTEFFICACY in tmInit().
*/
/*
        Note 2:

        Chrominance is optional in most of these routines, whether
        TM_F_BW is set or not.  Passing a value of TM_NOCHROM (or
        TM_NOCHROMP for picture reading) indicates that returned
        color values are not desired.
        
        If TM_NOCHROM is passed to a mapping routine expecting chroma
        input, it will do without it and return luminance channel
        rather than RGB pixel values.  Otherwise, the array for
        returned pixel values may be the same array used to pass
        encoded chrominances if no other mappings are desired.
*/
/*
        Note 3:

        Picture files may either be opened by the calling routine or by
        the library function.  If opened by the calling routine, the
        pointer to the stream is passed, which may be a pipe or other
        non-seekable input as it is only read once.  It must be
        positioned at the beginning when the function is called, and it
        will be positioned at the end on return.  It will not be closed.
        If the passed stream pointer is TM_GETFILE, then the library
        function will open the file, read its contents and close it
        before returning, whether or not an error was encountered.
*/

#ifdef __cplusplus
}
#endif
#endif /* _RAD_TONEMAP_H_ */

Revision:	3.15
Committed:	Mon Jul 14 04:56:54 2003 UTC (20 years, 9 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 3.14:	+28 -1 lines
Log Message:	Added tone-mapping support for 16-bit/sample int and IEEE float TIFF images
#	User	Rev	Content
1	greg	3.15	/* RCSid $Id: tonemap.h,v 3.14 2003/06/27 06:53:22 greg Exp $ */
2	greg	3.1	/*
3			* Header file for tone mapping functions.
4	gwlarson	3.8	*
5			* Include after "color.h"
6	greg	3.1	*/
7	schorsch	3.13	#ifndef _RAD_TONEMAP_H_
8			#define _RAD_TONEMAP_H_
9	greg	3.11	#ifdef __cplusplus
10			extern "C" {
11			#endif
12	schorsch	3.13
13	greg	3.15	#include "tifftypes.h"
14
15	greg	3.1	/** Argument Macros **/
16			/* Flags of what to do */
17			#define TM_F_HCONTR 01 /* human contrast sensitivity */
18			#define TM_F_MESOPIC 02 /* mesopic color sensitivity */
19			#define TM_F_LINEAR 04 /* linear brightness mapping */
20			#define TM_F_ACUITY 010 /* acuity adjustment */
21			#define TM_F_VEIL 020 /* veiling glare */
22			#define TM_F_CWEIGHT 040 /* center weighting */
23			#define TM_F_FOVEAL 0100 /* use foveal sample size */
24			#define TM_F_BW 0200 /* luminance only */
25	greg	3.2	#define TM_F_NOSTDERR 0400 /* don't report errors to stderr */
26	greg	3.1	/* combined modes */
27			#define TM_F_CAMERA 0
28			#define TM_F_HUMAN (TM_F_HCONTR\|TM_F_MESOPIC\|TM_F_VEIL\|\
29			TM_F_ACUITY\|TM_F_FOVEAL)
30			#define TM_F_UNIMPL (TM_F_CWEIGHT\|TM_F_VEIL\|TM_F_ACUITY\|TM_F_FOVEAL)
31
32			/* special pointer values */
33			#define TM_XYZPRIM (RGBPRIMP)NULL /* indicate XYZ primaries (Note 1) */
34			#define TM_NOCHROM (BYTE )NULL / indicate no chrominance */
35			#define TM_NOCHROMP (BYTE *)NULL / indicate no chrominances */
36			#define TM_GETFILE (FILE )NULL / indicate file must be opened */
37	gwlarson	3.8
38	greg	3.1
39			/** Error Return Values **/
40
41			#define TM_E_OK 0 /* normal return status */
42			#define TM_E_NOMEM 1 /* out of memory */
43			#define TM_E_ILLEGAL 2 /* illegal argument value */
44			#define TM_E_TMINVAL 3 /* no valid tone mapping */
45			#define TM_E_TMFAIL 4 /* cannot compute tone mapping */
46			#define TM_E_BADFILE 5 /* cannot open or understand file */
47	greg	3.4	#define TM_E_CODERR1 6 /* code consistency error 1 */
48			#define TM_E_CODERR2 7 /* code consistency error 2 */
49	greg	3.1
50	greg	3.4
51	greg	3.1	/** Conversion Constants and Table Sizes **/
52
53			#define TM_BRTSCALE 128 /* brightness scale factor (integer) */
54
55	gwlarson	3.10	#define TM_NOBRT (-1<<15) /* bogus brightness value */
56	greg	3.11	#define TM_NOLUM (1e-17) /* ridiculously small luminance */
57	gwlarson	3.10
58	greg	3.4	#define TM_MAXPKG 8 /* maximum number of color formats */
59	greg	3.1
60
61	greg	3.4	/** Global Data Types and Structures **/
62
63			#ifndef MEM_PTR
64			#define MEM_PTR void *
65			#endif
66
67	greg	3.1	extern char tmErrorMessage[]; / error messages */
68	gregl	3.6	extern int tmLastError; /* last error incurred by library */
69			extern char tmLastFunction; / error-generating function name */
70	greg	3.1
71			typedef short TMbright; /* encoded luminance type */
72
73			/* basic tone mapping data structure */
74			extern struct tmStruct {
75			int flags; /* flags of what to do */
76			RGBPRIMP monpri; /* monitor RGB primaries */
77			double mongam; /* monitor gamma value (approx.) */
78			COLOR clf; /* computed luminance coefficients */
79	greg	3.4	int cdiv[3]; /* computed color divisors */
80	greg	3.1	RGBPRIMP inppri; /* current input primaries */
81			double inpsf; /* current input scalefactor */
82			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			struct tmStruct tmprev; / previous tone mapping */
88	greg	3.4	MEM_PTR pd[TM_MAXPKG]; /* pointers to private data */
89	greg	3.1	} tmTop; / current tone mapping stack */
90	greg	3.4
91			/* conversion package functions */
92			struct tmPackage {
93			MEM_PTR (Init)(struct tmStruct tms);
94	greg	3.11	void (NewSpace)(struct tmStruct tms);
95	greg	3.4	void (*Free)(MEM_PTR pp);
96			};
97			/* our list of conversion packages */
98			extern struct tmPackage *tmPkg[TM_MAXPKG];
99			extern int tmNumPkgs; /* number of registered packages */
100
101
102	greg	3.1	/** Useful Macros **/
103
104	greg	3.4	/* compute luminance from encoded value */
105	greg	3.11	#define tmLuminance(li) exp((li)*(1./TM_BRTSCALE))
106	greg	3.1
107	greg	3.4	/* does tone mapping need color matrix? */
108			#define tmNeedMatrix(t) ((t)->monpri != (t)->inppri)
109
110			/* register a conversion package */
111			#define tmRegPkg(pf) ( tmNumPkgs >= TM_MAXPKG ? -1 : \
112			(tmPkg[tmNumPkgs] = (pf), tmNumPkgs++) )
113
114			/* get the specific package's data */
115			#define tmPkgData(t,i) ((t)->pd[i]!=NULL ? (t)->pd[i] : (*tmPkg[i]->Init)(t))
116
117
118	greg	3.1	/** Library Function Calls **/
119
120
121			extern struct tmStruct *
122			tmInit(int flags, RGBPRIMP monpri, double gamval);
123			/*
124			Initialize new tone mapping and push it onto stack.
125
126			flags - TM_F_* flags indicating what is to be done.
127			monpri - display monitor primaries (Note 1).
128			gamval - display gamma response (can be approximate).
129
130			returns - new tmTop, or NULL if insufficient memory.
131			*/
132
133			extern int
134			tmSetSpace(RGBPRIMP pri, double sf);
135			/*
136			Set color primaries and scale factor for incoming scanlines.
137
138			pri - RGB color input primaries (Note 1).
139			sf - scale factor to get to luminance in cd/m^2.
140
141			returns - 0 on success, TM_E_* code on failure.
142			*/
143
144			extern void
145			tmClearHisto(void);
146			/*
147			Clear histogram for current tone mapping.
148			*/
149
150			extern int
151			tmAddHisto(TMbright *ls, int len, int wt);
152			/*
153			Add brightness values to current histogram.
154
155			ls - encoded luminance values.
156			len - number of luminance values.
157			wt - integer weight to use for each value (usually 1 or -1).
158
159			returns - 0 on success, TM_E_* on error.
160			*/
161
162			extern int
163	greg	3.11	tmFixedMapping(double expmult, double gamval);
164			/*
165			Assign a fixed, linear tone-mapping using the given multiplier,
166			which is the ratio of maximum output to uncalibrated input.
167			This mapping will be used in subsequent calls to tmMapPixels()
168			until a new tone mapping is computed.
169			Only the min. and max. values are used from the histogram.
170
171			expmult - the fixed exposure multiplier to use.
172			gamval - display gamma response (0. for default).
173			returns - 0 on success, TM_E_* on error.
174			*/
175
176			extern int
177	greg	3.1	tmComputeMapping(double gamval, double Lddyn, double Ldmax);
178			/*
179	greg	3.11	Compute tone mapping function from the current histogram.
180			This mapping will be used in subsequent calls to tmMapPixels()
181			until a new tone mapping is computed.
182			I.e., calls to tmAddHisto() have no immediate effect.
183	greg	3.1
184			gamval - display gamma response (0. for default).
185			Lddyn - the display's dynamic range (0. for default).
186			Ldmax - maximum display luminance in cd/m^2 (0. for default).
187
188			returns - 0 on success, TM_E_* on failure.
189			*/
190
191			extern int
192			tmMapPixels(BYTE ps, TMbright ls, BYTE *cs, int len);
193			/*
194			Apply tone mapping function to pixel values.
195
196			ps - returned pixel values (Note 2).
197			ls - encoded luminance values.
198			cs - encoded chrominance values (Note 2).
199			len - number of pixels.
200
201			returns - 0 on success, TM_E_* on failure.
202			*/
203
204			extern struct tmStruct *
205			tmPop(void);
206			/*
207			Pops current tone mapping from stack.
208
209			returns - pointer to tone mapping structure, or NULL if none.
210			*/
211
212			extern int
213			tmPull(struct tmStruct *tms);
214			/*
215			Pull tone mapping from anywhere in stack.
216
217			tms - tone mapping structure to find.
218
219			returns - 1 if found in stack, 0 otherwise.
220			*/
221
222			extern int
223			tmPush(struct tmStruct *tms);
224			/*
225			Make tone mapping active by (pulling it and) pushing it to the top.
226
227			tms - initialized tone mapping structure.
228
229			returns - 0 on success, TM_E_* if tms is invalid.
230			*/
231
232	greg	3.3	extern struct tmStruct *
233			tmDup(void);
234			/*
235			Duplicate the current tone mapping into a new structure on the stack.
236
237			returns - pointer to new top, or NULL on error.
238			*/
239
240	greg	3.1	extern void
241			tmDone(struct tmStruct *tms);
242			/*
243			Free data associated with the given tone mapping structure.
244			Calls tmPull() first to remove it from the stack if present.
245			The calls tmDone(tmPop()), tmDone(tmTop) and tmDone(NULL)
246			all have the same effect, which is to remove and free
247			the current tone mapping.
248
249			tms - tone mapping structure to free.
250			*/
251
252	greg	3.11	extern int
253			tmCvColors(TMbright ls, BYTE cs, COLOR *scan, int len);
254			/*
255			Convert RGB/XYZ float scanline to encoded luminance and chrominance.
256
257			ls - returned encoded luminance values.
258			cs - returned encoded chrominance values (Note 2).
259			scan - input scanline.
260			len - scanline length.
261
262			returns - 0 on success, TM_E_* on error.
263			*/
264
265			extern int
266			tmCvGrays(TMbright ls, float scan, int len);
267			/*
268			Convert gray float scanline to encoded luminance.
269
270			ls - returned encoded luminance values.
271			scan - input scanline.
272			len - scanline length.
273
274			returns - 0 on success, TM_E_* on error.
275			*/
276
277			extern int
278			tmCvColrs(TMbright ls, BYTE cs, COLR *scan, int len);
279			/*
280			Convert RGBE/XYZE scanline to encoded luminance and chrominance.
281
282			ls - returned encoded luminance values.
283			cs - returned encoded chrominance values (Note 2).
284			scan - input scanline.
285			len - scanline length.
286
287			returns - 0 on success, TM_E_* on error.
288			*/
289
290			extern int
291			tmLoadPicture(TMbright lpp, BYTE cpp, int xp, int yp,
292			char fname, FILE fp);
293			/*
294			Load Radiance picture and convert to tone mapping representation.
295			Memory for the luminance and chroma arrays is allocated using
296			malloc(3), and should be freed with free(3) when no longer needed.
297			Calls tmSetSpace() to calibrate input color space.
298
299			lpp - returned array of encoded luminances, picture ordering.
300			cpp - returned array of encoded chrominances (Note 2).
301			xp, yp - returned picture dimensions.
302			fname - picture file name.
303			fp - pointer to open file (Note 3).
304
305			returns - 0 on success, TM_E_* on failure.
306			*/
307
308			extern int
309			tmMapPicture(BYTE *psp, int xp, int *yp, int flags,
310			RGBPRIMP monpri, double gamval, double Lddyn, double Ldmax,
311			char fname, FILE fp);
312			/*
313			Load and apply tone mapping to Radiance picture.
314			Stack is restored to its original state upon return.
315			If fp is TM_GETFILE and (flags&TM_F_UNIMPL)!=0, tmMapPicture()
316			calls pcond to perform the actual conversion, which takes
317			longer but gives access to all the TM_F_* features.
318			Memory for the final pixel array is allocated using malloc(3),
319			and should be freed with free(3) when it is no longer needed.
320
321			psp - returned array of tone mapped pixels, picture ordering.
322			xp, yp - returned picture dimensions.
323			flags - TM_F_* flags indicating what is to be done.
324			monpri - display monitor primaries (Note 1).
325			gamval - display gamma response.
326			Lddyn - the display's dynamic range (0. for default).
327			Ldmax - maximum display luminance in cd/m^2 (0. for default).
328			fname - picture file name.
329			fp - pointer to open file (Note 3).
330
331			returns - 0 on success, TM_E_* on failure.
332			*/
333
334	greg	3.15	extern int
335			tmCvRGB48(TMbright ls, BYTE cs, uint16 (*scan)[3], int len, double gv);
336			/*
337			Convert 48-bit RGB scanline to encoded luminance and chrominance.
338
339			ls - returned encoded luminance values.
340			cs - returned encoded chrominance values (Note 2).
341			scan - input scanline.
342			len - scanline length.
343			gv - input gamma value.
344
345			returns - 0 on success, TM_E_* on error.
346			*/
347
348			extern int
349			tmCvGray16(TMbright ls, uint16 scan, int len, double gv);
350			/*
351			Convert 16-bit gray scanline to encoded luminance.
352
353			ls - returned encoded luminance values.
354			scan - input scanline.
355			len - scanline length.
356			gv - input gamma value.
357	greg	3.4
358	greg	3.15	returns - 0 on success, TM_E_* on error.
359			*/
360	greg	3.4
361	greg	3.1	/** Notes **/
362			/*
363			General:
364
365			The usual sequence after calling tmInit() is to convert some
366			pixel values to chroma and luminance encodings, which can
367			be passed to tmAddHisto() to put into the tone mapping histogram.
368			This histogram is then used along with the display parameters
369	greg	3.5	by tmComputeMapping() to compute the luminance mapping function.
370	greg	3.1	(Colors are tone-mapped as they are converted if TM_F_MESOPIC
371			is set.) The encoded chroma and luminance values may then be
372			passed to tmMapPixels() to apply the computed tone mapping in
373			a second pass.
374
375			Especially for RGBE colors in the same color space as the
376			target display, the conversion to chroma and luminance values
377			is fast enough that it may be recomputed on the second pass
378			if memory is at a premium. (Since the chroma values are only
379			used during final mapping, setting the cs parameter to TM_NOCHROM
380			on the first pass will save time.) Another memory saving option
381			if third and subsequent passes are not needed is to use the
382	greg	3.3	same array to store the mapped pixels as used to store
383	greg	3.1	the encoded chroma values. This way, only two extra bytes
384			for storing encoded luminances are required per pixel. This
385			is the method employed by tmMapPicture(), for example.
386			*/
387			/*
388			Note 1:
389
390			All RGBPRIMP values should be pointers to static structures.
391			I.e., the same pointer should be used for the same primaries,
392			and those primaries should not change from one call to the next.
393			This is because the routines use the pointer value to identify
394			computed conversion matrices, so the matrices do not have to be
395			rebuilt each time. If you are using the standard primaries,
396			use the standard primary pointer, stdprims.
397
398			To indicate a set of input primaries are actually CIE XYZ,
399			the TM_XYZPRIM macro may be passed. If the input primaries
400			are unknown, it is wisest to pass tmTop->monpri to tmSetSpace().
401			By default, the input primaries equal the monitor primaries
402			and the scalefactor is set to WHTEFFICACY in tmInit().
403			*/
404			/*
405			Note 2:
406
407			Chrominance is optional in most of these routines, whether
408			TM_F_BW is set or not. Passing a value of TM_NOCHROM (or
409			TM_NOCHROMP for picture reading) indicates that returned
410			color values are not desired.
411
412			If TM_NOCHROM is passed to a mapping routine expecting chroma
413			input, it will do without it and return luminance channel
414			rather than RGB pixel values. Otherwise, the array for
415			returned pixel values may be the same array used to pass
416			encoded chrominances if no other mappings are desired.
417			*/
418			/*
419			Note 3:
420
421			Picture files may either be opened by the calling routine or by
422			the library function. If opened by the calling routine, the
423			pointer to the stream is passed, which may be a pipe or other
424			non-seekable input as it is only read once. It must be
425			positioned at the beginning when the function is called, and it
426			will be positioned at the end on return. It will not be closed.
427			If the passed stream pointer is TM_GETFILE, then the library
428			function will open the file, read its contents and close it
429			before returning, whether or not an error was encountered.
430			*/
431	greg	3.11
432			#ifdef __cplusplus
433			}
434			#endif
435	schorsch	3.13	#endif /* _RAD_TONEMAP_H_ */
436