src/common/tonemap.c

#ifndef lint
static const char       RCSid[] = "$Id: tonemap.c,v 3.20 2006/01/14 20:25:51 greg Exp $";
#endif
/*
 * Tone mapping functions.
 * See tonemap.h for detailed function descriptions.
 * Added von Kries white-balance calculations 10/01 (GW).
 *
 * Externals declared in tonemap.h
 */

#include "copyright.h"

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

#define exp10(x)        exp(M_LN10*(x))

                                        /* our list of conversion packages */
struct tmPackage        *tmPkg[TM_MAXPKG];
int     tmNumPkgs = 0;                  /* number of registered packages */


TMstruct *
tmInit(                                 /* initialize new tone mapping */
int     flags,
RGBPRIMP        monpri,
double  gamval
)
{
        COLORMAT        cmat;
        TMstruct        *tmnew;
        int     i;
                                                /* allocate structure */
        tmnew = (TMstruct *)malloc(sizeof(TMstruct));
        if (tmnew == NULL)
                return(NULL);

        tmnew->flags = flags & ~TM_F_UNIMPL;
        if (tmnew->flags & TM_F_BW)
                tmnew->flags &= ~TM_F_MESOPIC;
                                                /* set monitor transform */
        if (monpri == NULL || monpri == stdprims || tmnew->flags & TM_F_BW) {
                tmnew->monpri = stdprims;
                tmnew->clf[RED] = rgb2xyzmat[1][0];
                tmnew->clf[GRN] = rgb2xyzmat[1][1];
                tmnew->clf[BLU] = rgb2xyzmat[1][2];
        } else {
                comprgb2xyzWBmat(cmat, tmnew->monpri=monpri);
                tmnew->clf[RED] = cmat[1][0];
                tmnew->clf[GRN] = cmat[1][1];
                tmnew->clf[BLU] = cmat[1][2];
        }
                                                /* set gamma value */
        if (gamval < MINGAM)
                tmnew->mongam = DEFGAM;
        else
                tmnew->mongam = gamval;
                                                /* set color divisors */
        for (i = 0; i < 3; i++)
                tmnew->cdiv[i] = 256.*pow(tmnew->clf[i], 1./tmnew->mongam);

                                                /* set input transform */
        tmnew->inppri = tmnew->monpri;
        tmnew->cmat[0][0] = tmnew->cmat[1][1] = tmnew->cmat[2][2] =
                        tmnew->inpsf = WHTEFFICACY;
        tmnew->cmat[0][1] = tmnew->cmat[0][2] = tmnew->cmat[1][0] =
        tmnew->cmat[1][2] = tmnew->cmat[2][0] = tmnew->cmat[2][1] = 0.;
        tmnew->inpdat = NULL;
        tmnew->hbrmin = 10; tmnew->hbrmax = -10;
        tmnew->histo = NULL;
        tmnew->mbrmin = 10; tmnew->mbrmax = -10;
        tmnew->lumap = NULL;
                                                /* zero private data */
        for (i = TM_MAXPKG; i--; )
                tmnew->pd[i] = NULL;
        tmnew->lastError = TM_E_OK;
        tmnew->lastFunc = "NoErr";
                                                /* return new TMstruct */
        return(tmnew);
}


int
tmSetSpace(                     /* set input color space for conversions */
TMstruct        *tms,
RGBPRIMP        pri,
double  sf,
MEM_PTR dat
)
{
        static const char funcName[] = "tmSetSpace";
        int     i, j;
                                                /* error check */
        if (tms == NULL)
                returnErr(TM_E_TMINVAL);
        if (sf <= 1e-12)
                returnErr(TM_E_ILLEGAL);
                                                /* check if no change */
        if (pri == tms->inppri && FEQ(sf, tms->inpsf) && dat == tms->inpdat)
                returnOK;
        tms->inppri = pri;                      /* let's set it */
        tms->inpsf = sf;
        tms->inpdat = dat;

        if (tms->flags & TM_F_BW) {             /* color doesn't matter */
                tms->monpri = tms->inppri;              /* eliminate xform */
                if (tms->inppri == TM_XYZPRIM) {
                        tms->clf[CIEX] = tms->clf[CIEZ] = 0.;
                        tms->clf[CIEY] = 1.;
                } else {
                        comprgb2xyzWBmat(tms->cmat, tms->monpri);
                        tms->clf[RED] = tms->cmat[1][0];
                        tms->clf[GRN] = tms->cmat[1][1];
                        tms->clf[BLU] = tms->cmat[1][2];
                }
                tms->cmat[0][0] = tms->cmat[1][1] = tms->cmat[2][2] =
                                tms->inpsf;
                tms->cmat[0][1] = tms->cmat[0][2] = tms->cmat[1][0] =
                tms->cmat[1][2] = tms->cmat[2][0] = tms->cmat[2][1] = 0.;

        } else if (tms->inppri == TM_XYZPRIM)   /* input is XYZ */
                compxyz2rgbWBmat(tms->cmat, tms->monpri);

        else {                                  /* input is RGB */
                if (tms->inppri != tms->monpri &&
                                PRIMEQ(tms->inppri, tms->monpri))
                        tms->inppri = tms->monpri;      /* no xform */
                comprgb2rgbWBmat(tms->cmat, tms->inppri, tms->monpri);
        }
        for (i = 0; i < 3; i++)
                for (j = 0; j < 3; j++)
                        tms->cmat[i][j] *= tms->inpsf;
                                                /* set color divisors */
        for (i = 0; i < 3; i++)
                if (tms->clf[i] > .001)
                        tms->cdiv[i] =
                                256.*pow(tms->clf[i], 1./tms->mongam);
                else
                        tms->cdiv[i] = 1;
                                                /* notify packages */
        for (i = tmNumPkgs; i--; )
                if (tms->pd[i] != NULL && tmPkg[i]->NewSpace != NULL)
                        (*tmPkg[i]->NewSpace)(tms);
        returnOK;
}


void
tmClearHisto(                   /* clear current histogram */
TMstruct        *tms
)
{
        if (tms == NULL || tms->histo == NULL)
                return;
        free((MEM_PTR)tms->histo);
        tms->histo = NULL;
}


int
tmCvColors(                             /* convert float colors */
TMstruct        *tms,
TMbright        *ls,
BYTE    *cs,
COLOR   *scan,
int     len
)
{
        static const char funcName[] = "tmCvColors";
        static COLOR    csmall = {.5*MINLUM, .5*MINLUM, .5*MINLUM};
        static BYTE     gamtab[1024];
        static double   curgam = .0;
        COLOR   cmon;
        double  lum, slum;
        double  d;
        int     i;

        if (tms == NULL)
                returnErr(TM_E_TMINVAL);
        if ((ls == NULL) | (scan == NULL) | (len < 0))
                returnErr(TM_E_ILLEGAL);
        if (cs != TM_NOCHROM && fabs(tms->mongam - curgam) > .02) {
                curgam = tms->mongam;                   /* (re)build table */
                for (i = 1024; i--; )
                        gamtab[i] = (int)(256.*pow((i+.5)/1024., 1./curgam));
        }
        for (i = len; i--; ) {
                if (tmNeedMatrix(tms)) {                /* get monitor RGB */
                        colortrans(cmon, tms->cmat, scan[i]);
                } else {
                        cmon[RED] = tms->inpsf*scan[i][RED];
                        cmon[GRN] = tms->inpsf*scan[i][GRN];
                        cmon[BLU] = tms->inpsf*scan[i][BLU];
                }
                                                        /* world luminance */
                lum =   tms->clf[RED]*cmon[RED] +
                        tms->clf[GRN]*cmon[GRN] +
                        tms->clf[BLU]*cmon[BLU] ;
                                                        /* check range */
                if (clipgamut(cmon, lum, CGAMUT_LOWER, csmall, cwhite))
                        lum =   tms->clf[RED]*cmon[RED] +
                                tms->clf[GRN]*cmon[GRN] +
                                tms->clf[BLU]*cmon[BLU] ;
                if (lum < MINLUM) {
                        ls[i] = MINBRT-1;               /* bogus value */
                        lum = MINLUM;
                } else {
                        d = TM_BRTSCALE*log(lum);       /* encode it */
                        ls[i] = d>0. ? (int)(d+.5) : (int)(d-.5);
                }
                if (cs == TM_NOCHROM)                   /* no color? */
                        continue;
                if (tms->flags & TM_F_MESOPIC && lum < LMESUPPER) {
                        slum = scotlum(cmon);           /* mesopic adj. */
                        if (lum < LMESLOWER)
                                cmon[RED] = cmon[GRN] = cmon[BLU] = slum;
                        else {
                                d = (lum - LMESLOWER)/(LMESUPPER - LMESLOWER);
                                if (tms->flags & TM_F_BW)
                                        cmon[RED] = cmon[GRN] =
                                                        cmon[BLU] = d*lum;
                                else
                                        scalecolor(cmon, d);
                                d = (1.-d)*slum;
                                cmon[RED] += d;
                                cmon[GRN] += d;
                                cmon[BLU] += d;
                        }
                } else if (tms->flags & TM_F_BW) {
                        cmon[RED] = cmon[GRN] = cmon[BLU] = lum;
                }
                d = tms->clf[RED]*cmon[RED]/lum;
                cs[3*i  ] = d>=.999 ? 255 : gamtab[(int)(1024.*d)];
                d = tms->clf[GRN]*cmon[GRN]/lum;
                cs[3*i+1] = d>=.999 ? 255 : gamtab[(int)(1024.*d)];
                d = tms->clf[BLU]*cmon[BLU]/lum;
                cs[3*i+2] = d>=.999 ? 255 : gamtab[(int)(1024.*d)];
        }
        returnOK;
}


TMbright
tmCvLuminance(                          /* convert a single luminance */
double  lum
)
{
        double  d;

        if (lum <= TM_NOLUM)
                return(TM_NOBRT);
        d = TM_BRTSCALE*log(lum);
        if (d > 0.)
                return((TMbright)(d+.5));
        return((TMbright)(d-.5));
}


int
tmCvGrays(                              /* convert float gray values */
TMstruct        *tms,
TMbright        *ls,
float   *scan,
int     len
)
{
        static const char funcName[] = "tmCvGrays";
        double  d;
        int     i;

        if (tms == NULL)
                returnErr(TM_E_TMINVAL);
        if ((ls == NULL) | (scan == NULL) | (len < 0))
                returnErr(TM_E_ILLEGAL);
        for (i = len; i--; )
                if (scan[i] <= TM_NOLUM) {
                        ls[i] = TM_NOBRT;               /* bogus value */
                } else {
                        d = TM_BRTSCALE*log(scan[i]);   /* encode it */
                        ls[i] = d>0. ? (int)(d+.5) : (int)(d-.5);
                }
        returnOK;
}


int
tmAddHisto(                             /* add values to histogram */
TMstruct        *tms,
TMbright        *ls,
int     len,
int     wt
)
{
        static const char funcName[] = "tmAddHisto";
        int     oldorig=0, oldlen, horig, hlen;
        int     i, j;

        if (tms == NULL)
                returnErr(TM_E_TMINVAL);
        if (len < 0)
                returnErr(TM_E_ILLEGAL);
        if (len == 0)
                returnOK;
                                                /* first, grow limits */
        if (tms->histo == NULL) {
                for (i = len; i-- && ls[i] < MINBRT; )
                        ;
                if (i < 0)
                        returnOK;
                tms->hbrmin = tms->hbrmax = ls[i];
                oldlen = 0;
        } else {
                oldorig = (tms->hbrmin-MINBRT)/HISTEP;
                oldlen = (tms->hbrmax-MINBRT)/HISTEP + 1 - oldorig;
        }
        for (i = len; i--; ) {
                if ((j = ls[i]) < MINBRT)
                        continue;
                if (j < tms->hbrmin)
                        tms->hbrmin = j;
                else if (j > tms->hbrmax)
                        tms->hbrmax = j;
        }
        horig = (tms->hbrmin-MINBRT)/HISTEP;
        hlen = (tms->hbrmax-MINBRT)/HISTEP + 1 - horig;
        if (hlen > oldlen) {                    /* (re)allocate histogram */
                int     *newhist = (int *)calloc(hlen, sizeof(int));
                if (newhist == NULL)
                        returnErr(TM_E_NOMEM);
                if (oldlen) {                   /* copy and free old */
                        for (i = oldlen, j = i+oldorig-horig; i; )
                                newhist[--j] = tms->histo[--i];
                        free((MEM_PTR)tms->histo);
                }
                tms->histo = newhist;
        }
        if (wt == 0)
                returnOK;
        for (i = len; i--; )                    /* add in new counts */
                if (ls[i] >= MINBRT)
                        tms->histo[ (ls[i]-MINBRT)/HISTEP - horig ] += wt;
        returnOK;
}


static double
htcontrs(               /* human threshold contrast sensitivity, dL(La) */
double  La
)
{
        double  l10La, l10dL;
                                /* formula taken from Ferwerda et al. [SG96] */
        if (La < 1.148e-4)
                return(1.38e-3);
        l10La = log10(La);
        if (l10La < -1.44)              /* rod response regime */
                l10dL = pow(.405*l10La + 1.6, 2.18) - 2.86;
        else if (l10La < -.0184)
                l10dL = l10La - .395;
        else if (l10La < 1.9)           /* cone response regime */
                l10dL = pow(.249*l10La + .65, 2.7) - .72;
        else
                l10dL = l10La - 1.255;

        return(exp10(l10dL));
}


static int
tmNewMap(                       /* allocate new tone-mapping array */
TMstruct        *tms
)
{
        if (tms->lumap != NULL && (tms->mbrmax - tms->mbrmin) !=
                                        (tms->hbrmax - tms->hbrmin)) {
                free((MEM_PTR)tms->lumap);
                tms->lumap = NULL;
        }
        tms->mbrmin = tms->hbrmin;
        tms->mbrmax = tms->hbrmax;
        if (tms->mbrmin > tms->mbrmax)
                return 0;
        if (tms->lumap == NULL)
                tms->lumap = (unsigned short *)malloc(sizeof(unsigned short)*
                                        (tms->mbrmax-tms->mbrmin+1));
        return(tms->lumap != NULL);
}


int
tmFixedMapping(                 /* compute fixed, linear tone-mapping */
TMstruct        *tms,
double  expmult,
double  gamval
)
{
        static const char funcName[] = "tmFixedMapping";
        double          d;
        int     i;
        
        if (!tmNewMap(tms))
                returnErr(TM_E_NOMEM);
        if (expmult <= .0)
                expmult = 1.;
        if (gamval < MINGAM)
                gamval = tms->mongam;
        d = log(expmult/tms->inpsf);
        for (i = tms->mbrmax-tms->mbrmin+1; i--; )
                tms->lumap[i] = 256. * exp(
                        ( d + (tms->mbrmin+i)*(1./TM_BRTSCALE) )
                        / gamval );
        returnOK;
}


int
tmComputeMapping(                       /* compute histogram tone-mapping */
TMstruct        *tms,
double  gamval,
double  Lddyn,
double  Ldmax
)
{
        static const char funcName[] = "tmComputeMapping";
        int     *histo;
        float   *cumf;
        int     brt0, histlen, threshold, ceiling, trimmings;
        double  logLddyn, Ldmin, Ldavg, Lwavg, Tr, Lw, Ld;
        int32   histot;
        double  sum;
        double  d;
        int     i, j;

        if (tms == NULL || tms->histo == NULL)
                returnErr(TM_E_TMINVAL);
                                        /* check arguments */
        if (Lddyn < MINLDDYN) Lddyn = DEFLDDYN;
        if (Ldmax < MINLDMAX) Ldmax = DEFLDMAX;
        if (gamval < MINGAM) gamval = tms->mongam;
                                        /* compute handy values */
        Ldmin = Ldmax/Lddyn;
        logLddyn = log(Lddyn);
        Ldavg = sqrt(Ldmax*Ldmin);
        i = (tms->hbrmin-MINBRT)/HISTEP;
        brt0 = MINBRT + HISTEP/2 + i*HISTEP;
        histlen = (tms->hbrmax-MINBRT)/HISTEP + 1 - i;
                                        /* histogram total and mean */
        histot = 0; sum = 0;
        j = brt0 + histlen*HISTEP;
        for (i = histlen; i--; ) {
                histot += tms->histo[i];
                sum += (j -= HISTEP) * tms->histo[i];
        }
        threshold = histot*0.005 + .5;
        if (threshold < 4)
                returnErr(TM_E_TMFAIL);
        Lwavg = tmLuminance( (double)sum / histot );
                                        /* allocate space for mapping */
        if (!tmNewMap(tms))
                returnErr(TM_E_NOMEM);
                                        /* use linear tone mapping? */
        if (tms->flags & TM_F_LINEAR)
                goto linearmap;
                                        /* clamp histogram */
        histo = (int *)malloc(histlen*sizeof(int));
        cumf = (float *)malloc((histlen+2)*sizeof(float));
        if ((histo == NULL) | (cumf == NULL))
                returnErr(TM_E_NOMEM);
        cumf[histlen+1] = 1.;           /* guard for assignment code */
        for (i = histlen; i--; )        /* make malleable copy */
                histo[i] = tms->histo[i];
        do {                            /* iterate to solution */
                sum = 0;                /* cumulative probability */
                for (i = 0; i < histlen; i++) {
                        cumf[i] = (double)sum/histot;
                        sum += histo[i];
                }
                cumf[histlen] = 1.;
                Tr = histot * (double)(tms->hbrmax - tms->hbrmin) /
                        ((double)histlen*TM_BRTSCALE) / logLddyn;
                ceiling = Tr + 1.;
                trimmings = 0;          /* clip to envelope */
                for (i = histlen; i--; ) {
                        if (tms->flags & TM_F_HCONTR) {
                                Lw = tmLuminance(brt0 + i*HISTEP);
                                Ld = Ldmin * exp( logLddyn *
                                        .5*(cumf[i]+cumf[i+1]) );
                                ceiling = Tr * (htcontrs(Ld) * Lw) /
                                        (htcontrs(Lw) * Ld) + 1.;
                        }
                        if (histo[i] > ceiling) {
                                trimmings += histo[i] - ceiling;
                                histo[i] = ceiling;
                        }
                }
                                        /* check if we're out of data */
                if ((histot -= trimmings) <= threshold) {
                        free((MEM_PTR)histo);
                        free((MEM_PTR)cumf);
                        goto linearmap;
                }
        } while (trimmings > threshold);
                                        /* assign tone-mapping */
        for (i = tms->mbrmax-tms->mbrmin+1; i--; ) {
                j = d = (double)i/(tms->mbrmax-tms->mbrmin)*histlen;
                d -= (double)j;
                Ld = Ldmin*exp(logLddyn*((1.-d)*cumf[j]+d*cumf[j+1]));
                d = (Ld - Ldmin)/(Ldmax - Ldmin);
                tms->lumap[i] = 256.*pow(d, 1./gamval);
        }
        free((MEM_PTR)histo);           /* clean up and return */
        free((MEM_PTR)cumf);
        returnOK;
linearmap:                              /* linear tone-mapping */
        if (tms->flags & TM_F_HCONTR)
                d = htcontrs(Ldavg) / htcontrs(Lwavg);
        else
                d = Ldavg / Lwavg;
        return(tmFixedMapping(tms, tms->inpsf*d/Ldmax, gamval));
}


int
tmMapPixels(                    /* apply tone-mapping to pixel(s) */
TMstruct        *tms,
BYTE    *ps,
TMbright        *ls,
BYTE    *cs,
int     len
)
{
        static const char funcName[] = "tmMapPixels";
        int32   li, pv;

        if (tms == NULL || tms->lumap == NULL)
                returnErr(TM_E_TMINVAL);
        if ((ps == NULL) | (ls == NULL) | (len < 0))
                returnErr(TM_E_ILLEGAL);
        while (len--) {
                if ((li = *ls++) < tms->mbrmin) {
                        li = 0;
                } else {
                        if (li > tms->mbrmax)
                                li = tms->mbrmax;
                        li = tms->lumap[li - tms->mbrmin];
                }
                if (cs == TM_NOCHROM)
                        *ps++ = li>255 ? 255 : li;
                else {
                        pv = *cs++ * li / tms->cdiv[RED];
                        *ps++ = pv>255 ? 255 : pv;
                        pv = *cs++ * li / tms->cdiv[GRN];
                        *ps++ = pv>255 ? 255 : pv;
                        pv = *cs++ * li / tms->cdiv[BLU];
                        *ps++ = pv>255 ? 255 : pv;
                }
        }
        returnOK;
}


TMstruct *
tmDup(                          /* duplicate top tone mapping */
TMstruct        *tms
)
{
        int     len;
        int     i;
        TMstruct        *tmnew;

        if (tms == NULL)                /* anything to duplicate? */
                return(NULL);
        tmnew = (TMstruct *)malloc(sizeof(TMstruct));
        if (tmnew == NULL)
                return(NULL);
        *tmnew = *tms;          /* copy everything */
        if (tmnew->histo != NULL) {     /* duplicate histogram */
                len = (tmnew->hbrmax-MINBRT)/HISTEP + 1 -
                                (tmnew->hbrmin-MINBRT)/HISTEP;
                tmnew->histo = (int *)malloc(len*sizeof(int));
                if (tmnew->histo != NULL)
                        for (i = len; i--; )
                                tmnew->histo[i] = tms->histo[i];
        }
        if (tmnew->lumap != NULL) {     /* duplicate luminance mapping */
                len = tmnew->mbrmax-tmnew->mbrmin+1;
                tmnew->lumap = (unsigned short *)malloc(
                                                len*sizeof(unsigned short) );
                if (tmnew->lumap != NULL)
                        for (i = len; i--; )
                                tmnew->lumap[i] = tms->lumap[i];
        }
                                        /* clear package data */
        for (i = tmNumPkgs; i--; )
                tmnew->pd[i] = NULL;
                                        /* return copy */
        return(tmnew);
}


void
tmDone(tms)                     /* done with tone mapping -- destroy it */
TMstruct        *tms;
{
        int     i;
                                        /* NULL arg. is equiv. to tms */
        if (tms == NULL)
                return;
                                        /* free tables */
        if (tms->histo != NULL)
                free((MEM_PTR)tms->histo);
        if (tms->lumap != NULL)
                free((MEM_PTR)tms->lumap);
                                        /* free private data */
        for (i = tmNumPkgs; i--; )
                if (tms->pd[i] != NULL)
                        (*tmPkg[i]->Free)(tms->pd[i]);
        free((MEM_PTR)tms);             /* free basic structure */
}

/******************** Shared but Private library routines *********************/

BYTE    tmMesofact[BMESUPPER-BMESLOWER];

void
tmMkMesofact()                          /* build mesopic lookup factor table */
{
        int     i;

        if (tmMesofact[BMESUPPER-BMESLOWER-1])
                return;

        for (i = BMESLOWER; i < BMESUPPER; i++)
                tmMesofact[i-BMESLOWER] = 256. *
                                (tmLuminance(i) - LMESLOWER) /
                                (LMESUPPER - LMESLOWER);
}


int
tmErrorReturn(                          /* error return (with message) */
const char      *func,
TMstruct        *tms,
int     err
)
{
        if (tms != NULL) {
                tms->lastFunc = func;
                tms->lastError = err;
                if (tms->flags & TM_F_NOSTDERR)
                        return(err);
        }
        fputs(func, stderr);
        fputs(": ", stderr);
        fputs(tmErrorMessage[err], stderr);
        fputs("!\n", stderr);
        return(err);
}
Revision:	3.21
Committed:	Wed Jan 18 00:24:38 2006 UTC (18 years, 3 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 3.20:	+2 -2 lines
Log Message:	Bug fix in last change
#	User	Rev	Content
1	greg	3.1	#ifndef lint
2	greg	3.21	static const char RCSid[] = "$Id: tonemap.c,v 3.20 2006/01/14 20:25:51 greg Exp $";
3	greg	3.1	#endif
4			/*
5			* Tone mapping functions.
6			* See tonemap.h for detailed function descriptions.
7	greg	3.9	* Added von Kries white-balance calculations 10/01 (GW).
8			*
9			* Externals declared in tonemap.h
10			*/
11
12	greg	3.10	#include "copyright.h"
13	greg	3.1
14			#include <stdio.h>
15			#include <math.h>
16			#include "tmprivat.h"
17			#include "tmerrmsg.h"
18
19			#define exp10(x) exp(M_LN10*(x))
20
21	greg	3.4	/* our list of conversion packages */
22			struct tmPackage *tmPkg[TM_MAXPKG];
23			int tmNumPkgs = 0; /* number of registered packages */
24	greg	3.1
25	gregl	3.5
26	greg	3.16	TMstruct *
27			tmInit( /* initialize new tone mapping */
28			int flags,
29			RGBPRIMP monpri,
30			double gamval
31			)
32	greg	3.1	{
33			COLORMAT cmat;
34	greg	3.16	TMstruct *tmnew;
35			int i;
36	greg	3.1	/* allocate structure */
37	greg	3.16	tmnew = (TMstruct *)malloc(sizeof(TMstruct));
38	greg	3.1	if (tmnew == NULL)
39			return(NULL);
40
41			tmnew->flags = flags & ~TM_F_UNIMPL;
42	greg	3.15	if (tmnew->flags & TM_F_BW)
43			tmnew->flags &= ~TM_F_MESOPIC;
44	greg	3.1	/* set monitor transform */
45			if (monpri == NULL \|\| monpri == stdprims \|\| tmnew->flags & TM_F_BW) {
46			tmnew->monpri = stdprims;
47			tmnew->clf[RED] = rgb2xyzmat[1][0];
48			tmnew->clf[GRN] = rgb2xyzmat[1][1];
49			tmnew->clf[BLU] = rgb2xyzmat[1][2];
50			} else {
51	greg	3.9	comprgb2xyzWBmat(cmat, tmnew->monpri=monpri);
52	greg	3.1	tmnew->clf[RED] = cmat[1][0];
53			tmnew->clf[GRN] = cmat[1][1];
54			tmnew->clf[BLU] = cmat[1][2];
55			}
56			/* set gamma value */
57			if (gamval < MINGAM)
58			tmnew->mongam = DEFGAM;
59			else
60			tmnew->mongam = gamval;
61	greg	3.4	/* set color divisors */
62			for (i = 0; i < 3; i++)
63			tmnew->cdiv[i] = 256.*pow(tmnew->clf[i], 1./tmnew->mongam);
64
65	greg	3.1	/* set input transform */
66			tmnew->inppri = tmnew->monpri;
67			tmnew->cmat[0][0] = tmnew->cmat[1][1] = tmnew->cmat[2][2] =
68			tmnew->inpsf = WHTEFFICACY;
69			tmnew->cmat[0][1] = tmnew->cmat[0][2] = tmnew->cmat[1][0] =
70			tmnew->cmat[1][2] = tmnew->cmat[2][0] = tmnew->cmat[2][1] = 0.;
71	greg	3.18	tmnew->inpdat = NULL;
72	greg	3.9	tmnew->hbrmin = 10; tmnew->hbrmax = -10;
73	greg	3.1	tmnew->histo = NULL;
74	greg	3.9	tmnew->mbrmin = 10; tmnew->mbrmax = -10;
75	greg	3.1	tmnew->lumap = NULL;
76	greg	3.4	/* zero private data */
77			for (i = TM_MAXPKG; i--; )
78			tmnew->pd[i] = NULL;
79	greg	3.17	tmnew->lastError = TM_E_OK;
80			tmnew->lastFunc = "NoErr";
81	greg	3.16	/* return new TMstruct */
82			return(tmnew);
83	greg	3.1	}
84
85
86			int
87	greg	3.16	tmSetSpace( /* set input color space for conversions */
88			TMstruct *tms,
89			RGBPRIMP pri,
90	greg	3.18	double sf,
91			MEM_PTR dat
92	greg	3.16	)
93	greg	3.1	{
94	greg	3.17	static const char funcName[] = "tmSetSpace";
95	greg	3.16	int i, j;
96	greg	3.1	/* error check */
97	greg	3.16	if (tms == NULL)
98	greg	3.1	returnErr(TM_E_TMINVAL);
99			if (sf <= 1e-12)
100			returnErr(TM_E_ILLEGAL);
101			/* check if no change */
102	greg	3.18	if (pri == tms->inppri && FEQ(sf, tms->inpsf) && dat == tms->inpdat)
103	greg	3.1	returnOK;
104	greg	3.16	tms->inppri = pri; /* let's set it */
105			tms->inpsf = sf;
106	greg	3.18	tms->inpdat = dat;
107	greg	3.1
108	greg	3.16	if (tms->flags & TM_F_BW) { /* color doesn't matter */
109			tms->monpri = tms->inppri; /* eliminate xform */
110			if (tms->inppri == TM_XYZPRIM) {
111			tms->clf[CIEX] = tms->clf[CIEZ] = 0.;
112			tms->clf[CIEY] = 1.;
113	greg	3.1	} else {
114	greg	3.16	comprgb2xyzWBmat(tms->cmat, tms->monpri);
115			tms->clf[RED] = tms->cmat[1][0];
116			tms->clf[GRN] = tms->cmat[1][1];
117			tms->clf[BLU] = tms->cmat[1][2];
118			}
119			tms->cmat[0][0] = tms->cmat[1][1] = tms->cmat[2][2] =
120			tms->inpsf;
121			tms->cmat[0][1] = tms->cmat[0][2] = tms->cmat[1][0] =
122			tms->cmat[1][2] = tms->cmat[2][0] = tms->cmat[2][1] = 0.;
123	greg	3.1
124	greg	3.16	} else if (tms->inppri == TM_XYZPRIM) /* input is XYZ */
125			compxyz2rgbWBmat(tms->cmat, tms->monpri);
126	greg	3.1
127			else { /* input is RGB */
128	greg	3.16	if (tms->inppri != tms->monpri &&
129			PRIMEQ(tms->inppri, tms->monpri))
130			tms->inppri = tms->monpri; /* no xform */
131			comprgb2rgbWBmat(tms->cmat, tms->inppri, tms->monpri);
132	greg	3.1	}
133			for (i = 0; i < 3; i++)
134			for (j = 0; j < 3; j++)
135	greg	3.16	tms->cmat[i][j] *= tms->inpsf;
136	greg	3.4	/* set color divisors */
137			for (i = 0; i < 3; i++)
138	greg	3.16	if (tms->clf[i] > .001)
139			tms->cdiv[i] =
140			256.*pow(tms->clf[i], 1./tms->mongam);
141	greg	3.4	else
142	greg	3.16	tms->cdiv[i] = 1;
143	greg	3.4	/* notify packages */
144			for (i = tmNumPkgs; i--; )
145	greg	3.16	if (tms->pd[i] != NULL && tmPkg[i]->NewSpace != NULL)
146			(*tmPkg[i]->NewSpace)(tms);
147	greg	3.1	returnOK;
148			}
149
150
151			void
152	greg	3.16	tmClearHisto( /* clear current histogram */
153			TMstruct *tms
154			)
155	greg	3.1	{
156	greg	3.16	if (tms == NULL \|\| tms->histo == NULL)
157	greg	3.1	return;
158	greg	3.16	free((MEM_PTR)tms->histo);
159			tms->histo = NULL;
160	greg	3.1	}
161
162
163			int
164	greg	3.16	tmCvColors( /* convert float colors */
165			TMstruct *tms,
166			TMbright *ls,
167			BYTE *cs,
168			COLOR *scan,
169			int len
170			)
171	greg	3.1	{
172	greg	3.17	static const char funcName[] = "tmCvColors";
173	greg	3.12	static COLOR csmall = {.5MINLUM, .5MINLUM, .5*MINLUM};
174	greg	3.20	static BYTE gamtab[1024];
175			static double curgam = .0;
176	greg	3.1	COLOR cmon;
177			double lum, slum;
178	greg	3.16	double d;
179			int i;
180	greg	3.1
181	greg	3.16	if (tms == NULL)
182	greg	3.1	returnErr(TM_E_TMINVAL);
183	schorsch	3.13	if ((ls == NULL) \| (scan == NULL) \| (len < 0))
184	greg	3.1	returnErr(TM_E_ILLEGAL);
185	greg	3.21	if (cs != TM_NOCHROM && fabs(tms->mongam - curgam) > .02) {
186	greg	3.20	curgam = tms->mongam; /* (re)build table */
187			for (i = 1024; i--; )
188			gamtab[i] = (int)(256.*pow((i+.5)/1024., 1./curgam));
189			}
190	greg	3.1	for (i = len; i--; ) {
191	greg	3.16	if (tmNeedMatrix(tms)) { /* get monitor RGB */
192			colortrans(cmon, tms->cmat, scan[i]);
193	greg	3.15	} else {
194	greg	3.16	cmon[RED] = tms->inpsf*scan[i][RED];
195			cmon[GRN] = tms->inpsf*scan[i][GRN];
196			cmon[BLU] = tms->inpsf*scan[i][BLU];
197	greg	3.1	}
198			/* world luminance */
199	greg	3.16	lum = tms->clf[RED]*cmon[RED] +
200			tms->clf[GRN]*cmon[GRN] +
201			tms->clf[BLU]*cmon[BLU] ;
202	greg	3.1	/* check range */
203	greg	3.4	if (clipgamut(cmon, lum, CGAMUT_LOWER, csmall, cwhite))
204	greg	3.16	lum = tms->clf[RED]*cmon[RED] +
205			tms->clf[GRN]*cmon[GRN] +
206			tms->clf[BLU]*cmon[BLU] ;
207	greg	3.1	if (lum < MINLUM) {
208			ls[i] = MINBRT-1; /* bogus value */
209			lum = MINLUM;
210			} else {
211			d = TM_BRTSCALElog(lum); / encode it */
212			ls[i] = d>0. ? (int)(d+.5) : (int)(d-.5);
213			}
214			if (cs == TM_NOCHROM) /* no color? */
215			continue;
216	greg	3.16	if (tms->flags & TM_F_MESOPIC && lum < LMESUPPER) {
217	greg	3.1	slum = scotlum(cmon); /* mesopic adj. */
218			if (lum < LMESLOWER)
219			cmon[RED] = cmon[GRN] = cmon[BLU] = slum;
220			else {
221			d = (lum - LMESLOWER)/(LMESUPPER - LMESLOWER);
222	greg	3.16	if (tms->flags & TM_F_BW)
223	greg	3.1	cmon[RED] = cmon[GRN] =
224			cmon[BLU] = d*lum;
225			else
226			scalecolor(cmon, d);
227			d = (1.-d)*slum;
228			cmon[RED] += d;
229			cmon[GRN] += d;
230			cmon[BLU] += d;
231			}
232	greg	3.16	} else if (tms->flags & TM_F_BW) {
233	greg	3.1	cmon[RED] = cmon[GRN] = cmon[BLU] = lum;
234			}
235	greg	3.16	d = tms->clf[RED]*cmon[RED]/lum;
236	greg	3.20	cs[3i ] = d>=.999 ? 255 : gamtab[(int)(1024.d)];
237	greg	3.16	d = tms->clf[GRN]*cmon[GRN]/lum;
238	greg	3.20	cs[3i+1] = d>=.999 ? 255 : gamtab[(int)(1024.d)];
239	greg	3.16	d = tms->clf[BLU]*cmon[BLU]/lum;
240	greg	3.20	cs[3i+2] = d>=.999 ? 255 : gamtab[(int)(1024.d)];
241	greg	3.1	}
242			returnOK;
243			}
244
245
246	greg	3.19	TMbright
247			tmCvLuminance( /* convert a single luminance */
248			double lum
249			)
250			{
251			double d;
252
253			if (lum <= TM_NOLUM)
254			return(TM_NOBRT);
255			d = TM_BRTSCALE*log(lum);
256			if (d > 0.)
257			return((TMbright)(d+.5));
258			return((TMbright)(d-.5));
259			}
260
261
262	greg	3.1	int
263	greg	3.16	tmCvGrays( /* convert float gray values */
264			TMstruct *tms,
265			TMbright *ls,
266			float *scan,
267			int len
268			)
269	greg	3.9	{
270	greg	3.17	static const char funcName[] = "tmCvGrays";
271	greg	3.16	double d;
272			int i;
273	greg	3.9
274	greg	3.16	if (tms == NULL)
275	greg	3.9	returnErr(TM_E_TMINVAL);
276	schorsch	3.13	if ((ls == NULL) \| (scan == NULL) \| (len < 0))
277	greg	3.9	returnErr(TM_E_ILLEGAL);
278			for (i = len; i--; )
279			if (scan[i] <= TM_NOLUM) {
280			ls[i] = TM_NOBRT; /* bogus value */
281			} else {
282			d = TM_BRTSCALElog(scan[i]); / encode it */
283			ls[i] = d>0. ? (int)(d+.5) : (int)(d-.5);
284			}
285			returnOK;
286			}
287
288
289			int
290	greg	3.16	tmAddHisto( /* add values to histogram */
291			TMstruct *tms,
292			TMbright *ls,
293			int len,
294			int wt
295			)
296	greg	3.1	{
297	greg	3.17	static const char funcName[] = "tmAddHisto";
298	greg	3.9	int oldorig=0, oldlen, horig, hlen;
299	greg	3.16	int i, j;
300	greg	3.1
301	greg	3.16	if (tms == NULL)
302	greg	3.1	returnErr(TM_E_TMINVAL);
303	gwlarson	3.8	if (len < 0)
304			returnErr(TM_E_ILLEGAL);
305			if (len == 0)
306			returnOK;
307	greg	3.1	/* first, grow limits */
308	greg	3.16	if (tms->histo == NULL) {
309	greg	3.1	for (i = len; i-- && ls[i] < MINBRT; )
310			;
311			if (i < 0)
312			returnOK;
313	greg	3.16	tms->hbrmin = tms->hbrmax = ls[i];
314	greg	3.1	oldlen = 0;
315			} else {
316	greg	3.16	oldorig = (tms->hbrmin-MINBRT)/HISTEP;
317			oldlen = (tms->hbrmax-MINBRT)/HISTEP + 1 - oldorig;
318	greg	3.1	}
319			for (i = len; i--; ) {
320			if ((j = ls[i]) < MINBRT)
321			continue;
322	greg	3.16	if (j < tms->hbrmin)
323			tms->hbrmin = j;
324			else if (j > tms->hbrmax)
325			tms->hbrmax = j;
326	greg	3.1	}
327	greg	3.16	horig = (tms->hbrmin-MINBRT)/HISTEP;
328			hlen = (tms->hbrmax-MINBRT)/HISTEP + 1 - horig;
329	greg	3.1	if (hlen > oldlen) { /* (re)allocate histogram */
330	greg	3.16	int newhist = (int )calloc(hlen, sizeof(int));
331	greg	3.1	if (newhist == NULL)
332			returnErr(TM_E_NOMEM);
333			if (oldlen) { /* copy and free old */
334	greg	3.2	for (i = oldlen, j = i+oldorig-horig; i; )
335	greg	3.16	newhist[--j] = tms->histo[--i];
336			free((MEM_PTR)tms->histo);
337	greg	3.1	}
338	greg	3.16	tms->histo = newhist;
339	greg	3.1	}
340			if (wt == 0)
341			returnOK;
342			for (i = len; i--; ) /* add in new counts */
343			if (ls[i] >= MINBRT)
344	greg	3.16	tms->histo[ (ls[i]-MINBRT)/HISTEP - horig ] += wt;
345	greg	3.1	returnOK;
346			}
347
348
349			static double
350	greg	3.16	htcontrs( /* human threshold contrast sensitivity, dL(La) */
351			double La
352			)
353	greg	3.1	{
354			double l10La, l10dL;
355			/* formula taken from Ferwerda et al. [SG96] */
356			if (La < 1.148e-4)
357			return(1.38e-3);
358			l10La = log10(La);
359			if (l10La < -1.44) /* rod response regime */
360			l10dL = pow(.405*l10La + 1.6, 2.18) - 2.86;
361			else if (l10La < -.0184)
362			l10dL = l10La - .395;
363			else if (l10La < 1.9) /* cone response regime */
364			l10dL = pow(.249*l10La + .65, 2.7) - .72;
365			else
366			l10dL = l10La - 1.255;
367
368			return(exp10(l10dL));
369			}
370
371
372	greg	3.9	static int
373	greg	3.16	tmNewMap( /* allocate new tone-mapping array */
374			TMstruct *tms
375			)
376	greg	3.9	{
377	greg	3.16	if (tms->lumap != NULL && (tms->mbrmax - tms->mbrmin) !=
378			(tms->hbrmax - tms->hbrmin)) {
379			free((MEM_PTR)tms->lumap);
380			tms->lumap = NULL;
381			}
382			tms->mbrmin = tms->hbrmin;
383			tms->mbrmax = tms->hbrmax;
384			if (tms->mbrmin > tms->mbrmax)
385	greg	3.9	return 0;
386	greg	3.16	if (tms->lumap == NULL)
387			tms->lumap = (unsigned short )malloc(sizeof(unsigned short)
388			(tms->mbrmax-tms->mbrmin+1));
389			return(tms->lumap != NULL);
390	greg	3.9	}
391
392
393			int
394	greg	3.16	tmFixedMapping( /* compute fixed, linear tone-mapping */
395			TMstruct *tms,
396			double expmult,
397			double gamval
398			)
399	greg	3.9	{
400	greg	3.17	static const char funcName[] = "tmFixedMapping";
401	greg	3.9	double d;
402	greg	3.16	int i;
403	greg	3.9
404	greg	3.16	if (!tmNewMap(tms))
405	greg	3.9	returnErr(TM_E_NOMEM);
406			if (expmult <= .0)
407			expmult = 1.;
408			if (gamval < MINGAM)
409	greg	3.16	gamval = tms->mongam;
410			d = log(expmult/tms->inpsf);
411			for (i = tms->mbrmax-tms->mbrmin+1; i--; )
412			tms->lumap[i] = 256. * exp(
413			( d + (tms->mbrmin+i)*(1./TM_BRTSCALE) )
414	greg	3.9	/ gamval );
415			returnOK;
416			}
417
418
419	greg	3.1	int
420	greg	3.16	tmComputeMapping( /* compute histogram tone-mapping */
421			TMstruct *tms,
422			double gamval,
423			double Lddyn,
424			double Ldmax
425			)
426	greg	3.1	{
427	greg	3.17	static const char funcName[] = "tmComputeMapping";
428	greg	3.1	int *histo;
429			float *cumf;
430	greg	3.9	int brt0, histlen, threshold, ceiling, trimmings;
431	greg	3.1	double logLddyn, Ldmin, Ldavg, Lwavg, Tr, Lw, Ld;
432	greg	3.11	int32 histot;
433	greg	3.9	double sum;
434	greg	3.16	double d;
435			int i, j;
436	greg	3.1
437	greg	3.16	if (tms == NULL \|\| tms->histo == NULL)
438	greg	3.1	returnErr(TM_E_TMINVAL);
439			/* check arguments */
440			if (Lddyn < MINLDDYN) Lddyn = DEFLDDYN;
441			if (Ldmax < MINLDMAX) Ldmax = DEFLDMAX;
442	greg	3.16	if (gamval < MINGAM) gamval = tms->mongam;
443	greg	3.1	/* compute handy values */
444			Ldmin = Ldmax/Lddyn;
445			logLddyn = log(Lddyn);
446			Ldavg = sqrt(Ldmax*Ldmin);
447	greg	3.16	i = (tms->hbrmin-MINBRT)/HISTEP;
448	greg	3.1	brt0 = MINBRT + HISTEP/2 + i*HISTEP;
449	greg	3.16	histlen = (tms->hbrmax-MINBRT)/HISTEP + 1 - i;
450	greg	3.1	/* histogram total and mean */
451			histot = 0; sum = 0;
452			j = brt0 + histlen*HISTEP;
453			for (i = histlen; i--; ) {
454	greg	3.16	histot += tms->histo[i];
455			sum += (j -= HISTEP) * tms->histo[i];
456	greg	3.1	}
457	greg	3.14	threshold = histot*0.005 + .5;
458	greg	3.1	if (threshold < 4)
459			returnErr(TM_E_TMFAIL);
460			Lwavg = tmLuminance( (double)sum / histot );
461	greg	3.9	/* allocate space for mapping */
462	greg	3.16	if (!tmNewMap(tms))
463	greg	3.9	returnErr(TM_E_NOMEM);
464			/* use linear tone mapping? */
465	greg	3.16	if (tms->flags & TM_F_LINEAR)
466	greg	3.9	goto linearmap;
467			/* clamp histogram */
468			histo = (int )malloc(histlensizeof(int));
469			cumf = (float )malloc((histlen+2)sizeof(float));
470	schorsch	3.13	if ((histo == NULL) \| (cumf == NULL))
471	greg	3.9	returnErr(TM_E_NOMEM);
472			cumf[histlen+1] = 1.; /* guard for assignment code */
473			for (i = histlen; i--; ) /* make malleable copy */
474	greg	3.16	histo[i] = tms->histo[i];
475	greg	3.9	do { /* iterate to solution */
476			sum = 0; /* cumulative probability */
477			for (i = 0; i < histlen; i++) {
478			cumf[i] = (double)sum/histot;
479			sum += histo[i];
480			}
481			cumf[histlen] = 1.;
482	greg	3.16	Tr = histot * (double)(tms->hbrmax - tms->hbrmin) /
483	greg	3.9	((double)histlen*TM_BRTSCALE) / logLddyn;
484			ceiling = Tr + 1.;
485			trimmings = 0; /* clip to envelope */
486			for (i = histlen; i--; ) {
487	greg	3.16	if (tms->flags & TM_F_HCONTR) {
488	greg	3.9	Lw = tmLuminance(brt0 + i*HISTEP);
489			Ld = Ldmin * exp( logLddyn *
490			.5*(cumf[i]+cumf[i+1]) );
491			ceiling = Tr * (htcontrs(Ld) * Lw) /
492			(htcontrs(Lw) * Ld) + 1.;
493	greg	3.2	}
494	greg	3.9	if (histo[i] > ceiling) {
495			trimmings += histo[i] - ceiling;
496			histo[i] = ceiling;
497	greg	3.1	}
498			}
499	greg	3.9	/* check if we're out of data */
500			if ((histot -= trimmings) <= threshold) {
501			free((MEM_PTR)histo);
502			free((MEM_PTR)cumf);
503			goto linearmap;
504			}
505			} while (trimmings > threshold);
506			/* assign tone-mapping */
507	greg	3.16	for (i = tms->mbrmax-tms->mbrmin+1; i--; ) {
508			j = d = (double)i/(tms->mbrmax-tms->mbrmin)*histlen;
509	greg	3.9	d -= (double)j;
510			Ld = Ldminexp(logLddyn((1.-d)cumf[j]+dcumf[j+1]));
511			d = (Ld - Ldmin)/(Ldmax - Ldmin);
512	greg	3.16	tms->lumap[i] = 256.*pow(d, 1./gamval);
513	greg	3.1	}
514	greg	3.9	free((MEM_PTR)histo); /* clean up and return */
515			free((MEM_PTR)cumf);
516	greg	3.1	returnOK;
517	greg	3.9	linearmap: /* linear tone-mapping */
518	greg	3.16	if (tms->flags & TM_F_HCONTR)
519	greg	3.9	d = htcontrs(Ldavg) / htcontrs(Lwavg);
520			else
521			d = Ldavg / Lwavg;
522	greg	3.16	return(tmFixedMapping(tms, tms->inpsf*d/Ldmax, gamval));
523	greg	3.1	}
524
525
526			int
527	greg	3.16	tmMapPixels( /* apply tone-mapping to pixel(s) */
528			TMstruct *tms,
529			BYTE *ps,
530			TMbright *ls,
531			BYTE *cs,
532			int len
533			)
534	greg	3.1	{
535	greg	3.17	static const char funcName[] = "tmMapPixels";
536	greg	3.16	int32 li, pv;
537	greg	3.1
538	greg	3.16	if (tms == NULL \|\| tms->lumap == NULL)
539	greg	3.1	returnErr(TM_E_TMINVAL);
540	schorsch	3.13	if ((ps == NULL) \| (ls == NULL) \| (len < 0))
541	greg	3.1	returnErr(TM_E_ILLEGAL);
542			while (len--) {
543	greg	3.16	if ((li = *ls++) < tms->mbrmin) {
544	greg	3.9	li = 0;
545			} else {
546	greg	3.16	if (li > tms->mbrmax)
547			li = tms->mbrmax;
548			li = tms->lumap[li - tms->mbrmin];
549	greg	3.9	}
550	greg	3.1	if (cs == TM_NOCHROM)
551			*ps++ = li>255 ? 255 : li;
552			else {
553	greg	3.16	pv = cs++ li / tms->cdiv[RED];
554	greg	3.1	*ps++ = pv>255 ? 255 : pv;
555	greg	3.16	pv = cs++ li / tms->cdiv[GRN];
556	greg	3.1	*ps++ = pv>255 ? 255 : pv;
557	greg	3.16	pv = cs++ li / tms->cdiv[BLU];
558	greg	3.1	*ps++ = pv>255 ? 255 : pv;
559			}
560			}
561			returnOK;
562			}
563
564
565
566
567	greg	3.16	TMstruct *
568			tmDup( /* duplicate top tone mapping */
569			TMstruct *tms
570			)
571	greg	3.3	{
572			int len;
573	greg	3.16	int i;
574			TMstruct *tmnew;
575	greg	3.3
576	greg	3.16	if (tms == NULL) /* anything to duplicate? */
577	greg	3.3	return(NULL);
578	greg	3.16	tmnew = (TMstruct *)malloc(sizeof(TMstruct));
579	greg	3.3	if (tmnew == NULL)
580			return(NULL);
581	greg	3.16	tmnew = tms; /* copy everything */
582	greg	3.3	if (tmnew->histo != NULL) { /* duplicate histogram */
583	gregl	3.6	len = (tmnew->hbrmax-MINBRT)/HISTEP + 1 -
584			(tmnew->hbrmin-MINBRT)/HISTEP;
585	greg	3.3	tmnew->histo = (int )malloc(lensizeof(int));
586			if (tmnew->histo != NULL)
587			for (i = len; i--; )
588	greg	3.16	tmnew->histo[i] = tms->histo[i];
589	greg	3.3	}
590			if (tmnew->lumap != NULL) { /* duplicate luminance mapping */
591	gregl	3.6	len = tmnew->mbrmax-tmnew->mbrmin+1;
592	greg	3.3	tmnew->lumap = (unsigned short *)malloc(
593			len*sizeof(unsigned short) );
594			if (tmnew->lumap != NULL)
595			for (i = len; i--; )
596	greg	3.16	tmnew->lumap[i] = tms->lumap[i];
597	greg	3.3	}
598	greg	3.4	/* clear package data */
599			for (i = tmNumPkgs; i--; )
600			tmnew->pd[i] = NULL;
601	greg	3.16	/* return copy */
602			return(tmnew);
603	greg	3.1	}
604
605
606			void
607			tmDone(tms) /* done with tone mapping -- destroy it */
608	greg	3.16	TMstruct *tms;
609	greg	3.1	{
610	greg	3.16	int i;
611			/* NULL arg. is equiv. to tms */
612			if (tms == NULL)
613	greg	3.1	return;
614			/* free tables */
615			if (tms->histo != NULL)
616	greg	3.4	free((MEM_PTR)tms->histo);
617	greg	3.1	if (tms->lumap != NULL)
618	greg	3.4	free((MEM_PTR)tms->lumap);
619			/* free private data */
620			for (i = tmNumPkgs; i--; )
621			if (tms->pd[i] != NULL)
622			(*tmPkg[i]->Free)(tms->pd[i]);
623			free((MEM_PTR)tms); /* free basic structure */
624	greg	3.9	}
625
626			/****************** Shared but Private library routines *******************/
627
628			BYTE tmMesofact[BMESUPPER-BMESLOWER];
629
630			void
631			tmMkMesofact() /* build mesopic lookup factor table */
632			{
633	greg	3.16	int i;
634	greg	3.9
635			if (tmMesofact[BMESUPPER-BMESLOWER-1])
636			return;
637
638			for (i = BMESLOWER; i < BMESUPPER; i++)
639			tmMesofact[i-BMESLOWER] = 256. *
640			(tmLuminance(i) - LMESLOWER) /
641			(LMESUPPER - LMESLOWER);
642			}
643
644
645			int
646	greg	3.16	tmErrorReturn( /* error return (with message) */
647	greg	3.17	const char *func,
648	greg	3.16	TMstruct *tms,
649			int err
650			)
651	greg	3.9	{
652	greg	3.17	if (tms != NULL) {
653			tms->lastFunc = func;
654			tms->lastError = err;
655			if (tms->flags & TM_F_NOSTDERR)
656			return(err);
657			}
658	greg	3.9	fputs(func, stderr);
659			fputs(": ", stderr);
660			fputs(tmErrorMessage[err], stderr);
661			fputs("!\n", stderr);
662			return(err);
663	greg	3.1	}