src/common/tmap16bit.c

#ifndef lint
static const char RCSid[] = "$Id: tmap16bit.c,v 1.3 2003/07/15 07:28:09 greg Exp $";
#endif
/*
 * Routines for tone-mapping 16-bit/primary pixels
 *
 * Externals declared in tonemap.h
 */

#include "copyright.h"

#include <stdio.h>
#include <math.h>
#include "tmprivat.h"

#define LOGTABBITS      11      /* log table is 1<<LOGTABBITS long */
#define GAMTABBITS      9       /* gamma table is 1<<GAMTABBITS long */
#define MONGAMTSZ       1024    /* monitor gamma table length */

static float    logtab[1<<LOGTABBITS];
static float    gamtab[1<<GAMTABBITS];
static float    gammul[16];
static double   cur_gam = 0.;
static BYTE     mongamtab[MONGAMTSZ];
static double   cur_mongam = 0.;

#define imultpow2(i,s)  ((s)>=0 ? (i)<<(s) : (i)>>-(s))


/* Fill our log table */
static void
mkLogTable()
{       
        int     i;

        if (logtab[0] != 0.f)
                return;
        for (i = 1<<LOGTABBITS; i--; )
                logtab[i] = log(imultpow2(i,15-LOGTABBITS)*(1./(1L<<16))
                                        + .5);
}


/* Fill our input gamma table */
static void
mkGamTable(double gv)
{
        int     i;

        if (gv == cur_gam)
                return;
        for (i = 1<<GAMTABBITS; i--; )
                gamtab[i] = pow((i+.5)*(1./(1<<GAMTABBITS)), gv);
        for (i = 16; i--; )
                gammul[i] = pow((double)(1L<<i), -gv);
        cur_gam = gv;
}


/* Fill our monitor gamma table */
static void
mkMonGamTable()
{
        int     i;
        
        if (tmTop->mongam == cur_mongam)
                return;
        for (i = MONGAMTSZ; i--; )
                mongamtab[i] = 256.*pow((i+.5)*(1./MONGAMTSZ), 1./tmTop->mongam);
        cur_mongam = tmTop->mongam;
}


/* Find normalizing shift value for a 2-byte unsigned integer */
static int
normShift16(int i)
{
        int     s = 0;
        
        if (!i)
                return(-1);
        while (!(i & 0x8000)) {
                i <<= 1;
                ++s;
        }
        return(s);
}


/* Find common normalizing shift for 3 2-byte unsigned integers */
static int
normShift48(uint16 clr48[3])
{
        int     imax = (clr48[1] > clr48[0] ? clr48[1] : clr48[0]);
        if (clr48[2] > imax)
                imax = clr48[2];
        return(normShift16(imax));
}


/* convert at 48-bit tristimulus value to a COLOR */
static void
rgb48_color(COLOR col, uint16 clr48[3], double gv)
{
        int     nshft;

        if (gv == 1.) {                         /* linear case */
                col[0] = clr48[0]*(1./(1L<<16));
                col[1] = clr48[1]*(1./(1L<<16));
                col[2] = clr48[2]*(1./(1L<<16));
                return;
        }
                                                /* non-linear case */
        /* XXX Uncomment if this routine is made public
        if (gv != cur_gam)
                mkGamTable(gv);
        */
        nshft = normShift48(clr48);
        if (nshft < 0) {
                col[0] = col[1] = col[2] = .0f;
                return;
        }
        col[0] = gamtab[imultpow2(clr48[0],GAMTABBITS-16+nshft)] * 
                        gammul[nshft];
        col[1] = gamtab[imultpow2(clr48[1],GAMTABBITS-16+nshft)] *
                        gammul[nshft];
        col[2] = gamtab[imultpow2(clr48[2],GAMTABBITS-16+nshft)] *
                        gammul[nshft];
}


/* Convert 16-bit gray scanline to encoded luminance */
int
tmCvGray16(TMbright *ls, uint16 *scan, int len, double gv)
{
        static char     funcName[] = "tmCvGray16";
        static double   cur_inpsf = 1.;
        static double   log_inpsf = 0.;
        int             nshft;
        double          d;

        if (tmTop == NULL)
                returnErr(TM_E_TMINVAL);
        if ((ls == NULL) | (scan == NULL) | (len < 0))
                returnErr(TM_E_ILLEGAL);
        if (gv <= 0.)
                gv = DEFGAM;
                                                /* initialize log table */
        if (logtab[0] == 0.f)
                mkLogTable();
        if (cur_inpsf != tmTop->inpsf)
                log_inpsf = log(cur_inpsf = tmTop->inpsf);
                                                /* convert 16-bit grays */
        while (len--) {
                nshft = normShift16(*scan);
                if (nshft < 0) {                /* bogus value */
                        *ls++ = TM_NOBRT;
                        scan++;
                        continue;
                }
                d = logtab[ imultpow2(*scan,LOGTABBITS-15+nshft) &
                                        ((1L<<LOGTABBITS)-1) ];
                d -= M_LN2*nshft;
                d = (double)TM_BRTSCALE * (gv*d + log_inpsf);
                *ls++ = (d>0. ? d+.5 : d-.5);
                scan++;
        }
        returnOK;
}

/* Convert a 48-bit RGB scanline to encoded luminance/chrominance */
int
tmCvRGB48(TMbright *ls, BYTE *cs, uint16 (*scan)[3], int len, double gv)
{
        static char     funcName[] = "tmCvRGB48";
        static double   cur_inpsf = 1.;
        static double   log_inpsf = 0.;
        int             i;

        if (tmTop == NULL)
                returnErr(TM_E_TMINVAL);
        if ((ls == NULL) | (scan == NULL) | (len < 0))
                returnErr(TM_E_ILLEGAL);
        if (gv <= 0.)
                gv = DEFGAM;
                                                /* sync input gamma table */
        if ((gv != 1.) & (gv != cur_gam))
                mkGamTable(gv);
        if (tmNeedMatrix(tmTop)) {              /* need floating point */
                COLOR   *newscan;
                newscan = (COLOR *)tempbuffer(len*sizeof(COLOR));
                if (newscan == NULL)
                        returnErr(TM_E_NOMEM);
                for (i = len; i--; )
                        rgb48_color(newscan[i], scan[i], gv);
                return(tmCvColors(ls, cs, newscan, len));
        }
                                                /* sync monitor gamma table */
        if (cs != TM_NOCHROM && tmTop->mongam != cur_mongam)
                mkMonGamTable();
                                                /* initialize log table */
        if (logtab[0] == 0.f)
                mkLogTable();
        if (cur_inpsf != tmTop->inpsf)
                log_inpsf = log(cur_inpsf = tmTop->inpsf);
        if (tmTop->flags & TM_F_MESOPIC)
                tmMkMesofact();
                                                /* convert scanline */
        for (i = len; i--; ) {
                int     nshft = normShift48(scan[i]);
                COLOR   cmon;
                double  lum;
                int     bi;
                
                if (nshft < 0) {
                        bi = TM_NOBRT;                  /* bogus value */
                        lum = 1.;
                } else {
                        int     j = GAMTABBITS-16+nshft;
                        int     nshft2;
                        double  d;
                                                        /* normalized linear */
                        setcolor(cmon,  gamtab[imultpow2(scan[i][0],j)],
                                        gamtab[imultpow2(scan[i][1],j)],
                                        gamtab[imultpow2(scan[i][2],j)] );
                        lum =   tmTop->clf[RED]*cmon[RED];
                        lum +=  tmTop->clf[GRN]*cmon[GRN];
                        lum +=  tmTop->clf[BLU]*cmon[BLU];
                                                        /* convert to log Y */
                        j = lum * (double)(1L<<16);
                        nshft2 = normShift16(j);
                        d = logtab[ imultpow2(j,LOGTABBITS-15+nshft2) &
                                                ((1L<<LOGTABBITS)-1) ];
                        d -= M_LN2*(gv*nshft + nshft2);
                        d = (double)TM_BRTSCALE*(d + log_inpsf);
                        bi = (int)(d>0. ? d+.5 : d-.5);
                }
                                                        /* world luminance */
                ls[i] = bi;
                if (cs == TM_NOCHROM)                   /* no color? */
                        continue;
                                                        /* mesopic adj. */
                if (tmTop->flags & TM_F_MESOPIC && bi < BMESUPPER) {
                        double  slum = scotlum(cmon);
                        if (bi < BMESLOWER)
                                setcolor(cmon, slum, slum, slum);
                        else {
                                double  pf;
                                pf = (1./256.)*tmMesofact[bi-BMESLOWER];
                                if (tmTop->flags & TM_F_BW)
                                        cmon[RED] = cmon[GRN] = cmon[BLU] = lum;
                                slum *= 1. - pf;
                                cmon[RED] = slum + pf*cmon[RED];
                                cmon[GRN] = slum + pf*cmon[GRN];
                                cmon[BLU] = slum + pf*cmon[BLU];
                        }
                } else if (tmTop->flags & TM_F_BW) {
                        cmon[RED] = cmon[GRN] = cmon[BLU] = lum;
                }
                bi = (double)MONGAMTSZ*tmTop->clf[RED]*cmon[RED]/lum;
                cs[3*i  ] = bi>=MONGAMTSZ ? 255 : mongamtab[bi];
                bi = (double)MONGAMTSZ*tmTop->clf[GRN]*cmon[GRN]/lum;
                cs[3*i+1] = bi>=MONGAMTSZ ? 255 : mongamtab[bi];
                bi = (double)MONGAMTSZ*tmTop->clf[BLU]*cmon[BLU]/lum;
                cs[3*i+2] = bi>=MONGAMTSZ ? 255 : mongamtab[bi];
        }
        returnOK;
}
Revision:	1.4
Committed:	Sun Jul 27 22:12:01 2003 UTC (20 years, 9 months ago) by schorsch
Content type:	text/plain
Branch:	MAIN
CVS Tags:	rad3R6, rad3R6P1
Changes since 1.3:	+4 -4 lines
Log Message:	Added grouping parens to reduce ambiguity warnings.
#	User	Rev	Content
1	greg	1.1	#ifndef lint
2	schorsch	1.4	static const char RCSid[] = "$Id: tmap16bit.c,v 1.3 2003/07/15 07:28:09 greg Exp $";
3	greg	1.1	#endif
4			/*
5			* Routines for tone-mapping 16-bit/primary pixels
6			*
7			* Externals declared in tonemap.h
8			*/
9
10			#include "copyright.h"
11
12			#include <stdio.h>
13			#include <math.h>
14			#include "tmprivat.h"
15
16			#define LOGTABBITS 11 /* log table is 1<<LOGTABBITS long */
17			#define GAMTABBITS 9 /* gamma table is 1<<GAMTABBITS long */
18	greg	1.3	#define MONGAMTSZ 1024 /* monitor gamma table length */
19	greg	1.1
20			static float logtab[1<<LOGTABBITS];
21			static float gamtab[1<<GAMTABBITS];
22			static float gammul[16];
23			static double cur_gam = 0.;
24	greg	1.3	static BYTE mongamtab[MONGAMTSZ];
25			static double cur_mongam = 0.;
26	greg	1.1
27			#define imultpow2(i,s) ((s)>=0 ? (i)<<(s) : (i)>>-(s))
28
29
30			/* Fill our log table */
31			static void
32			mkLogTable()
33			{
34			int i;
35
36			if (logtab[0] != 0.f)
37			return;
38			for (i = 1<<LOGTABBITS; i--; )
39			logtab[i] = log(imultpow2(i,15-LOGTABBITS)*(1./(1L<<16))
40			+ .5);
41			}
42
43
44	greg	1.3	/* Fill our input gamma table */
45	greg	1.1	static void
46			mkGamTable(double gv)
47			{
48			int i;
49
50			if (gv == cur_gam)
51			return;
52			for (i = 1<<GAMTABBITS; i--; )
53			gamtab[i] = pow((i+.5)*(1./(1<<GAMTABBITS)), gv);
54			for (i = 16; i--; )
55			gammul[i] = pow((double)(1L<<i), -gv);
56			cur_gam = gv;
57			}
58
59
60	greg	1.3	/* Fill our monitor gamma table */
61			static void
62			mkMonGamTable()
63			{
64			int i;
65
66			if (tmTop->mongam == cur_mongam)
67			return;
68			for (i = MONGAMTSZ; i--; )
69			mongamtab[i] = 256.pow((i+.5)(1./MONGAMTSZ), 1./tmTop->mongam);
70			cur_mongam = tmTop->mongam;
71			}
72
73
74	greg	1.1	/* Find normalizing shift value for a 2-byte unsigned integer */
75			static int
76			normShift16(int i)
77			{
78			int s = 0;
79
80	greg	1.2	if (!i)
81			return(-1);
82	greg	1.1	while (!(i & 0x8000)) {
83			i <<= 1;
84			++s;
85			}
86			return(s);
87			}
88
89
90			/* Find common normalizing shift for 3 2-byte unsigned integers */
91			static int
92			normShift48(uint16 clr48[3])
93			{
94			int imax = (clr48[1] > clr48[0] ? clr48[1] : clr48[0]);
95			if (clr48[2] > imax)
96			imax = clr48[2];
97			return(normShift16(imax));
98			}
99
100
101			/* convert at 48-bit tristimulus value to a COLOR */
102			static void
103	greg	1.2	rgb48_color(COLOR col, uint16 clr48[3], double gv)
104	greg	1.1	{
105			int nshft;
106
107	greg	1.2	if (gv == 1.) { /* linear case */
108	greg	1.1	col[0] = clr48[0]*(1./(1L<<16));
109			col[1] = clr48[1]*(1./(1L<<16));
110			col[2] = clr48[2]*(1./(1L<<16));
111			return;
112			}
113			/* non-linear case */
114	greg	1.3	/* XXX Uncomment if this routine is made public
115	greg	1.2	if (gv != cur_gam)
116			mkGamTable(gv);
117			*/
118	greg	1.1	nshft = normShift48(clr48);
119	greg	1.2	if (nshft < 0) {
120			col[0] = col[1] = col[2] = .0f;
121			return;
122			}
123	greg	1.1	col[0] = gamtab[imultpow2(clr48[0],GAMTABBITS-16+nshft)] *
124			gammul[nshft];
125			col[1] = gamtab[imultpow2(clr48[1],GAMTABBITS-16+nshft)] *
126			gammul[nshft];
127			col[2] = gamtab[imultpow2(clr48[2],GAMTABBITS-16+nshft)] *
128			gammul[nshft];
129			}
130
131
132			/* Convert 16-bit gray scanline to encoded luminance */
133			int
134			tmCvGray16(TMbright ls, uint16 scan, int len, double gv)
135			{
136			static char funcName[] = "tmCvGray16";
137			static double cur_inpsf = 1.;
138			static double log_inpsf = 0.;
139			int nshft;
140			double d;
141
142			if (tmTop == NULL)
143			returnErr(TM_E_TMINVAL);
144	schorsch	1.4	if ((ls == NULL) \| (scan == NULL) \| (len < 0))
145	greg	1.1	returnErr(TM_E_ILLEGAL);
146	greg	1.2	if (gv <= 0.)
147			gv = DEFGAM;
148	greg	1.1	/* initialize log table */
149			if (logtab[0] == 0.f)
150			mkLogTable();
151			if (cur_inpsf != tmTop->inpsf)
152			log_inpsf = log(cur_inpsf = tmTop->inpsf);
153			/* convert 16-bit grays */
154			while (len--) {
155			nshft = normShift16(*scan);
156	greg	1.2	if (nshft < 0) { /* bogus value */
157			*ls++ = TM_NOBRT;
158			scan++;
159			continue;
160			}
161	greg	1.1	d = logtab[ imultpow2(*scan,LOGTABBITS-15+nshft) &
162	greg	1.3	((1L<<LOGTABBITS)-1) ];
163			d -= M_LN2*nshft;
164	greg	1.1	d = (double)TM_BRTSCALE * (gv*d + log_inpsf);
165			*ls++ = (d>0. ? d+.5 : d-.5);
166			scan++;
167			}
168			returnOK;
169			}
170
171			/* Convert a 48-bit RGB scanline to encoded luminance/chrominance */
172			int
173			tmCvRGB48(TMbright ls, BYTE cs, uint16 (*scan)[3], int len, double gv)
174			{
175			static char funcName[] = "tmCvRGB48";
176			static double cur_inpsf = 1.;
177			static double log_inpsf = 0.;
178			int i;
179
180			if (tmTop == NULL)
181			returnErr(TM_E_TMINVAL);
182	schorsch	1.4	if ((ls == NULL) \| (scan == NULL) \| (len < 0))
183	greg	1.1	returnErr(TM_E_ILLEGAL);
184	greg	1.2	if (gv <= 0.)
185			gv = DEFGAM;
186	greg	1.3	/* sync input gamma table */
187	schorsch	1.4	if ((gv != 1.) & (gv != cur_gam))
188	greg	1.1	mkGamTable(gv);
189			if (tmNeedMatrix(tmTop)) { /* need floating point */
190			COLOR *newscan;
191			newscan = (COLOR )tempbuffer(lensizeof(COLOR));
192			if (newscan == NULL)
193			returnErr(TM_E_NOMEM);
194			for (i = len; i--; )
195	greg	1.2	rgb48_color(newscan[i], scan[i], gv);
196	greg	1.1	return(tmCvColors(ls, cs, newscan, len));
197			}
198	greg	1.3	/* sync monitor gamma table */
199			if (cs != TM_NOCHROM && tmTop->mongam != cur_mongam)
200			mkMonGamTable();
201	greg	1.1	/* initialize log table */
202			if (logtab[0] == 0.f)
203			mkLogTable();
204			if (cur_inpsf != tmTop->inpsf)
205			log_inpsf = log(cur_inpsf = tmTop->inpsf);
206	greg	1.3	if (tmTop->flags & TM_F_MESOPIC)
207			tmMkMesofact();
208	greg	1.1	/* convert scanline */
209			for (i = len; i--; ) {
210	greg	1.3	int nshft = normShift48(scan[i]);
211			COLOR cmon;
212			double lum;
213			int bi;
214
215			if (nshft < 0) {
216	greg	1.1	bi = TM_NOBRT; /* bogus value */
217	greg	1.3	lum = 1.;
218			} else {
219			int j = GAMTABBITS-16+nshft;
220			int nshft2;
221			double d;
222			/* normalized linear */
223			setcolor(cmon, gamtab[imultpow2(scan[i][0],j)],
224			gamtab[imultpow2(scan[i][1],j)],
225			gamtab[imultpow2(scan[i][2],j)] );
226			lum = tmTop->clf[RED]*cmon[RED];
227			lum += tmTop->clf[GRN]*cmon[GRN];
228			lum += tmTop->clf[BLU]*cmon[BLU];
229			/* convert to log Y */
230			j = lum * (double)(1L<<16);
231			nshft2 = normShift16(j);
232			d = logtab[ imultpow2(j,LOGTABBITS-15+nshft2) &
233			((1L<<LOGTABBITS)-1) ];
234			d -= M_LN2(gvnshft + nshft2);
235			d = (double)TM_BRTSCALE*(d + log_inpsf);
236			bi = (int)(d>0. ? d+.5 : d-.5);
237	greg	1.1	}
238	greg	1.3	/* world luminance */
239	greg	1.1	ls[i] = bi;
240			if (cs == TM_NOCHROM) /* no color? */
241			continue;
242			/* mesopic adj. */
243			if (tmTop->flags & TM_F_MESOPIC && bi < BMESUPPER) {
244	greg	1.3	double slum = scotlum(cmon);
245	greg	1.1	if (bi < BMESLOWER)
246	greg	1.3	setcolor(cmon, slum, slum, slum);
247	greg	1.1	else {
248	greg	1.3	double pf;
249			pf = (1./256.)*tmMesofact[bi-BMESLOWER];
250	greg	1.1	if (tmTop->flags & TM_F_BW)
251	greg	1.3	cmon[RED] = cmon[GRN] = cmon[BLU] = lum;
252			slum *= 1. - pf;
253			cmon[RED] = slum + pf*cmon[RED];
254			cmon[GRN] = slum + pf*cmon[GRN];
255			cmon[BLU] = slum + pf*cmon[BLU];
256	greg	1.1	}
257			} else if (tmTop->flags & TM_F_BW) {
258	greg	1.3	cmon[RED] = cmon[GRN] = cmon[BLU] = lum;
259	greg	1.1	}
260	greg	1.3	bi = (double)MONGAMTSZtmTop->clf[RED]cmon[RED]/lum;
261			cs[3*i ] = bi>=MONGAMTSZ ? 255 : mongamtab[bi];
262			bi = (double)MONGAMTSZtmTop->clf[GRN]cmon[GRN]/lum;
263			cs[3*i+1] = bi>=MONGAMTSZ ? 255 : mongamtab[bi];
264			bi = (double)MONGAMTSZtmTop->clf[BLU]cmon[BLU]/lum;
265			cs[3*i+2] = bi>=MONGAMTSZ ? 255 : mongamtab[bi];
266	greg	1.1	}
267			returnOK;
268			}