--- ray/src/px/pcond4.c 1996/10/03 16:52:51 3.1 +++ ray/src/px/pcond4.c 2004/11/08 15:50:59 3.18 @@ -1,46 +1,45 @@ -/* Copyright (c) 1996 Regents of the University of California */ - #ifndef lint -static char SCCSid[] = "$SunId$ LBL"; +static const char RCSid[] = "$Id: pcond4.c,v 3.18 2004/11/08 15:50:59 greg Exp $"; #endif - /* * Routines for veiling glare and loss of acuity. */ #include "pcond.h" +/************** VEILING STUFF *****************/ #define VADAPT 0.08 /* fraction of adaptation from veil */ -extern COLOR *fovimg; /* foveal (1 degree) averaged image */ -extern short fvxr, fvyr; /* foveal image resolution */ +static COLOR *veilimg = NULL; /* veiling image */ -#define fovscan(y) (fovimg+(y)*fvxr) - -static COLOR *veilimg; /* veiling image */ - #define veilscan(y) (veilimg+(y)*fvxr) -static FVECT *raydir = NULL; /* ray direction for each pixel */ +static float (*raydir)[3] = NULL; /* ray direction for each pixel */ #define rdirscan(y) (raydir+(y)*fvxr) +static void compraydir(void); +#if ADJ_VEIL +static void smoothveil(void); +#endif -compraydir() /* compute ray directions */ + +static void +compraydir(void) /* compute ray directions */ { - FVECT rorg; + FVECT rorg, rdir; double h, v; register int x, y; if (raydir != NULL) /* already done? */ return; - raydir = (FVECT *)malloc(fvxr*fvyr*sizeof(FVECT)); + raydir = (float (*)[3])malloc(fvxr*fvyr*3*sizeof(float)); if (raydir == NULL) syserror("malloc"); for (y = 0; y < fvyr; y++) { - switch (inpres.or) { + switch (inpres.rt) { case YMAJOR: case YMAJOR|XDECR: v = (y+.5)/fvyr; break; case YMAJOR|YDECR: case YMAJOR|YDECR|XDECR: @@ -51,7 +50,7 @@ compraydir() /* compute ray directions */ h = 1. - (y+.5)/fvyr; break; } for (x = 0; x < fvxr; x++) { - switch (inpres.or) { + switch (inpres.rt) { case YMAJOR: case YMAJOR|YDECR: h = (x+.5)/fvxr; break; case YMAJOR|XDECR: case YMAJOR|XDECR|YDECR: @@ -61,8 +60,12 @@ compraydir() /* compute ray directions */ case YDECR: case YDECR|XDECR: v = 1. - (x+.5)/fvxr; break; } - if (viewray(rorg, rdirscan(y)[x], &ourview, h, v) - < -FTINY) { + if (viewray(rorg, rdir, &ourview, h, v) + >= -FTINY) { + rdirscan(y)[x][0] = rdir[0]; + rdirscan(y)[x][1] = rdir[1]; + rdirscan(y)[x][2] = rdir[2]; + } else { rdirscan(y)[x][0] = rdirscan(y)[x][1] = rdirscan(y)[x][2] = 0.0; @@ -72,12 +75,16 @@ compraydir() /* compute ray directions */ } -compveil() /* compute veiling image */ +extern void +compveil(void) /* compute veiling image */ { double t2, t2sum; COLOR ctmp, vsum; int px, py; register int x, y; + + if (veilimg != NULL) /* already done? */ + return; /* compute ray directions */ compraydir(); /* compute veil image */ @@ -94,35 +101,176 @@ compveil() /* compute veiling image */ t2 = DOT(rdirscan(py)[px], rdirscan(y)[x]); if (t2 <= FTINY) continue; - t2 = acos(t2); - t2 = 1./(t2*t2); + /* use approximation instead + t3 = acos(t2); + t2 = t2/(t3*t3); + */ + t2 *= .5 / (1. - t2); copycolor(ctmp, fovscan(y)[x]); scalecolor(ctmp, t2); addcolor(vsum, ctmp); t2sum += t2; } /* VADAPT of original is subtracted in addveil() */ - scalecolor(vsum, VADAPT/t2sum); + if (t2sum > FTINY) + scalecolor(vsum, VADAPT/t2sum); copycolor(veilscan(py)[px], vsum); } + /* modify FOV sample image */ + for (y = 0; y < fvyr; y++) + for (x = 0; x < fvxr; x++) { + scalecolor(fovscan(y)[x], 1.-VADAPT); + addcolor(fovscan(y)[x], veilscan(y)[x]); + } + comphist(); /* recompute histogram */ } -addveil(sl, y) /* add veil to scanline */ -COLOR *sl; -int y; +#if ADJ_VEIL +/* + * The following veil adjustment was added to compensate for + * the fact that contrast reduction gets confused with veil + * in the human visual system. Therefore, we reduce the + * veil in portions of the image where our mapping has + * already reduced contrast below the target value. + * This gets called after the intial veil has been computed + * and added to the foveal image, and the mapping has been + * determined. + */ +extern void +adjveil(void) /* adjust veil image */ { + float *crfptr = crfimg; + COLOR *fovptr = fovimg; + COLOR *veilptr = veilimg; + double s2nits = 1./inpexp; + double vl, vl2, fovl, vlsum; + double deltavc[3]; + int i, j; + + if (lumf == rgblum) + s2nits *= WHTEFFICACY; + + for (i = fvxr*fvyr; i--; crfptr++, fovptr++, veilptr++) { + if (crfptr[0] >= 0.95) + continue; + vl = plum(veilptr[0]); + fovl = (plum(fovptr[0]) - vl) * (1./(1.-VADAPT)); + if (vl <= 0.05*fovl) + continue; + vlsum = vl; + for (j = 2; j < 11; j++) { + vlsum += crfptr[0]*vl - (1.0 - crfptr[0])*fovl; + vl2 = vlsum / (double)j; + if (vl2 < 0.0) + vl2 = 0.0; + crfptr[0] = crfactor(fovl + vl2); + } + /* desaturation code causes color fringes at this level */ + for (j = 3; j--; ) { + double vc = colval(veilptr[0],j); + double fovc = (colval(fovptr[0],j) - vc) * + (1./(1.-VADAPT)); + deltavc[j] = (1.-crfptr[0])*(fovl/s2nits - fovc); + if (vc + deltavc[j] < 0.0) + break; + } + if (j < 0) + addcolor(veilptr[0], deltavc); + else + scalecolor(veilptr[0], vl2/vl); + } + smoothveil(); /* smooth our result */ +} + + +static void +smoothveil(void) /* smooth veil image */ +{ + COLOR *nveilimg; + COLOR *ovptr, *nvptr; + int x, y, i; + + nveilimg = (COLOR *)malloc(fvxr*fvyr*sizeof(COLOR)); + if (nveilimg == NULL) + return; + for (y = 1; y < fvyr-1; y++) { + ovptr = veilimg + y*fvxr + 1; + nvptr = nveilimg + y*fvxr + 1; + for (x = 1; x < fvxr-1; x++, ovptr++, nvptr++) + for (i = 3; i--; ) + nvptr[0][i] = 0.5 * ovptr[0][i] + + (1./12.) * + (ovptr[-1][i] + ovptr[-fvxr][i] + + ovptr[1][i] + ovptr[fvxr][i]) + + (1./24.) * + (ovptr[-fvxr-1][i] + ovptr[-fvxr+1][i] + + ovptr[fvxr-1][i] + ovptr[fvxr+1][i]); + } + ovptr = veilimg + 1; + nvptr = nveilimg + 1; + for (x = 1; x < fvxr-1; x++, ovptr++, nvptr++) + for (i = 3; i--; ) + nvptr[0][i] = 0.5 * ovptr[0][i] + + (1./9.) * + (ovptr[-1][i] + ovptr[1][i] + ovptr[fvxr][i]) + + (1./12.) * + (ovptr[fvxr-1][i] + ovptr[fvxr+1][i]); + ovptr = veilimg + (fvyr-1)*fvxr + 1; + nvptr = nveilimg + (fvyr-1)*fvxr + 1; + for (x = 1; x < fvxr-1; x++, ovptr++, nvptr++) + for (i = 3; i--; ) + nvptr[0][i] = 0.5 * ovptr[0][i] + + (1./9.) * + (ovptr[-1][i] + ovptr[1][i] + ovptr[-fvxr][i]) + + (1./12.) * + (ovptr[-fvxr-1][i] + ovptr[-fvxr+1][i]); + ovptr = veilimg + fvxr; + nvptr = nveilimg + fvxr; + for (y = 1; y < fvyr-1; y++, ovptr += fvxr, nvptr += fvxr) + for (i = 3; i--; ) + nvptr[0][i] = 0.5 * ovptr[0][i] + + (1./9.) * + (ovptr[-fvxr][i] + ovptr[1][i] + ovptr[fvxr][i]) + + (1./12.) * + (ovptr[-fvxr+1][i] + ovptr[fvxr+1][i]); + ovptr = veilimg + fvxr - 1; + nvptr = nveilimg + fvxr - 1; + for (y = 1; y < fvyr-1; y++, ovptr += fvxr, nvptr += fvxr) + for (i = 3; i--; ) + nvptr[0][i] = 0.5 * ovptr[0][i] + + (1./9.) * + (ovptr[-fvxr][i] + ovptr[-1][i] + ovptr[fvxr][i]) + + (1./12.) * + (ovptr[-fvxr-1][i] + ovptr[fvxr-1][i]); + for (i = 3; i--; ) { + nveilimg[0][i] = veilimg[0][i]; + nveilimg[fvxr-1][i] = veilimg[fvxr-1][i]; + nveilimg[(fvyr-1)*fvxr][i] = veilimg[(fvyr-1)*fvxr][i]; + nveilimg[fvyr*fvxr-1][i] = veilimg[fvyr*fvxr-1][i]; + } + free((void *)veilimg); + veilimg = nveilimg; +} +#endif + +extern void +addveil( /* add veil to scanline */ + COLOR *sl, + int y +) +{ int vx, vy; double dx, dy; double lv, uv; register int x, i; vy = dy = (y+.5)/numscans(&inpres)*fvyr - .5; - if (vy >= fvyr-1) vy--; + while (vy >= fvyr-1) vy--; dy -= (double)vy; for (x = 0; x < scanlen(&inpres); x++) { vx = dx = (x+.5)/scanlen(&inpres)*fvxr - .5; - if (vx >= fvxr-1) vx--; + while (vx >= fvxr-1) vx--; dx -= (double)vx; for (i = 0; i < 3; i++) { lv = (1.-dy)*colval(veilscan(vy)[vx],i) + @@ -133,4 +281,260 @@ int y; (1.-dx)*lv + dx*uv; } } +} + + +/****************** ACUITY STUFF *******************/ + +typedef struct { + short sampe; /* sample area size (exponent of 2) */ + short nscans; /* number of scanlines in this bar */ + int len; /* individual scanline length */ + int nread; /* number of scanlines loaded */ + COLOR *sdata; /* scanbar data */ +} SCANBAR; + +#define bscan(sb,y) ((COLOR *)(sb)->sdata+((y)%(sb)->nscans)*(sb)->len) + +SCANBAR *rootbar; /* root scan bar (lowest resolution) */ + +float *inpacuD = NULL; /* input acuity data (cycles/degree) */ + +#define tsampr(x,y) inpacuD[(y)*fvxr+(x)] + +static COLOR * getascan(SCANBAR *sb, int y); +static void acusample(COLOR col, int x, int y, double sr); +static void ascanval(COLOR col, int x, int y, SCANBAR *sb); +static SCANBAR *sballoc(int se, int ns, int sl); + +extern double +hacuity( /* return visual acuity in cycles/degree */ + double La +) +{ + /* functional fit */ + return(17.25*atan(1.4*log10(La) + 0.35) + 25.72); +} + + +static COLOR * +getascan( /* find/read scanline y for scanbar sb */ + register SCANBAR *sb, + int y +) +{ + register COLOR *sl0, *sl1, *mysl; + register int i; + + if (y < sb->nread - sb->nscans) /* too far back? */ + return(NULL); + for ( ; y >= sb->nread; sb->nread++) { /* read as necessary */ + mysl = bscan(sb, sb->nread); + if (sb->sampe == 0) { + if (freadscan(mysl, sb->len, infp) < 0) { + fprintf(stderr, "%s: %s: scanline read error\n", + progname, infn); + exit(1); + } + } else { + sl0 = getascan(sb+1, 2*y); + if (sl0 == NULL) + return(NULL); + sl1 = getascan(sb+1, 2*y+1); + for (i = 0; i < sb->len; i++) { + copycolor(mysl[i], sl0[2*i]); + addcolor(mysl[i], sl0[2*i+1]); + addcolor(mysl[i], sl1[2*i]); + addcolor(mysl[i], sl1[2*i+1]); + scalecolor(mysl[i], 0.25); + } + } + } + return(bscan(sb, y)); +} + + +extern void +acuscan( /* get acuity-sampled scanline */ + COLOR *scln, + int y +) +{ + double sr; + double dx, dy; + int ix, iy; + register int x; + + if (inpacuD == NULL) + return; + /* compute foveal y position */ + iy = dy = (y+.5)/numscans(&inpres)*fvyr - .5; + while (iy >= fvyr-1) iy--; + dy -= (double)iy; + for (x = 0; x < scanlen(&inpres); x++) { + /* compute foveal x position */ + ix = dx = (x+.5)/scanlen(&inpres)*fvxr - .5; + while (ix >= fvxr-1) ix--; + dx -= (double)ix; + /* interpolate sample rate */ + sr = (1.-dy)*((1.-dx)*tsampr(ix,iy) + dx*tsampr(ix+1,iy)) + + dy*((1.-dx)*tsampr(ix,iy+1) + dx*tsampr(ix+1,iy+1)); + + acusample(scln[x], x, y, sr); /* compute sample */ + } +} + + +static void +acusample( /* interpolate sample at (x,y) using rate sr */ + COLOR col, + int x, + int y, + double sr +) +{ + COLOR c1; + double d; + register SCANBAR *sb0; + + for (sb0 = rootbar; sb0->sampe != 0 && 1< sr; sb0++) + ; + ascanval(col, x, y, sb0); + if (sb0->sampe == 0) /* don't extrapolate highest */ + return; + ascanval(c1, x, y, sb0+1); + d = ((1<sampe) - sr)/(1<sampe == 0) { /* no need to interpolate */ + sl0 = getascan(sb, y); + copycolor(col, sl0[x]); + return; + } + /* compute coordinates for sb */ + ix = dx = (x+.5)/(1<sampe) - .5; + while (ix >= sb->len-1) ix--; + dx -= (double)ix; + iy = dy = (y+.5)/(1<sampe) - .5; + while (iy >= (numscans(&inpres)>>sb->sampe)-1) iy--; + dy -= (double)iy; + /* get scanlines */ + sl0 = getascan(sb, iy); +#ifdef DEBUG + if (sl0 == NULL) + error(INTERNAL, "cannot backspace in ascanval"); +#endif + sl1 = getascan(sb, iy+1); + /* 2D linear interpolation */ + copycolor(col, sl0[ix]); + scalecolor(col, 1.-dx); + copycolor(c1, sl0[ix+1]); + scalecolor(c1, dx); + addcolor(col, c1); + copycolor(c1y, sl1[ix]); + scalecolor(c1y, 1.-dx); + copycolor(c1, sl1[ix+1]); + scalecolor(c1, dx); + addcolor(c1y, c1); + scalecolor(col, 1.-dy); + scalecolor(c1y, dy); + addcolor(col, c1y); + for (ix = 0; ix < 3; ix++) /* make sure no negative */ + if (colval(col,ix) < 0.) + colval(col,ix) = 0.; +} + + +static SCANBAR * +sballoc( /* allocate scanbar */ + int se, /* sampling rate exponent */ + int ns, /* number of scanlines */ + int sl /* original scanline length */ +) +{ + SCANBAR *sbarr; + register SCANBAR *sb; + + sbarr = sb = (SCANBAR *)malloc((se+1)*sizeof(SCANBAR)); + if (sb == NULL) + syserror("malloc"); + do { + sb->len = sl>>se; + if (sb->len <= 0) + continue; + sb->sampe = se; + sb->nscans = ns; + sb->sdata = (COLOR *)malloc(sb->len*ns*sizeof(COLOR)); + if (sb->sdata == NULL) + syserror("malloc"); + sb->nread = 0; + ns <<= 1; + sb++; + } while (--se >= 0); + return(sbarr); +} + + +extern int +initacuity(void) /* initialize variable acuity sampling */ +{ + FVECT diffx, diffy, cp; + double omega, maxsr; + register int x, y, i; + + if (fvxr < 3 || fvyr < 3) + return(0); /* too small to work with */ + + compraydir(); /* compute ray directions */ + + inpacuD = (float *)malloc(fvxr*fvyr*sizeof(float)); + if (inpacuD == NULL) + syserror("malloc"); + maxsr = 1.; /* compute internal sample rates */ + for (y = 1; y < fvyr-1; y++) + for (x = 1; x < fvxr-1; x++) { + for (i = 0; i < 3; i++) { + diffx[i] = 0.5*fvxr/scanlen(&inpres) * + (rdirscan(y)[x+1][i] - + rdirscan(y)[x-1][i]); + diffy[i] = 0.5*fvyr/numscans(&inpres) * + (rdirscan(y+1)[x][i] - + rdirscan(y-1)[x][i]); + } + fcross(cp, diffx, diffy); + omega = 0.5 * sqrt(DOT(cp,cp)); + if (omega <= FTINY*FTINY) + tsampr(x,y) = 1.; + else if ((tsampr(x,y) = PI/180. / sqrt(omega) / + hacuity(plum(fovscan(y)[x]))) > maxsr) + maxsr = tsampr(x,y); + } + /* copy perimeter (easier) */ + for (x = 1; x < fvxr-1; x++) { + tsampr(x,0) = tsampr(x,1); + tsampr(x,fvyr-1) = tsampr(x,fvyr-2); + } + for (y = 0; y < fvyr; y++) { + tsampr(0,y) = tsampr(1,y); + tsampr(fvxr-1,y) = tsampr(fvxr-2,y); + } + /* initialize with next power of two */ + rootbar = sballoc((int)(log(maxsr)/log(2.))+1, 2, scanlen(&inpres)); + return(1); }