| 1 |
– |
/* Copyright (c) 1992 Regents of the University of California */ |
| 2 |
– |
|
| 1 |
|
#ifndef lint |
| 2 |
< |
static char SCCSid[] = "$SunId$ LBL"; |
| 2 |
> |
static const char RCSid[] = "$Id$"; |
| 3 |
|
#endif |
| 6 |
– |
|
| 4 |
|
/* |
| 5 |
|
* pf3.c - routines for gaussian and box filtering |
| 6 |
|
* |
| 7 |
|
* 8/13/86 |
| 8 |
|
*/ |
| 9 |
|
|
| 10 |
< |
#include <stdio.h> |
| 10 |
> |
#include "standard.h" |
| 11 |
|
|
| 12 |
< |
#include <math.h> |
| 12 |
> |
#include <string.h> |
| 13 |
|
|
| 14 |
|
#include "color.h" |
| 15 |
+ |
#include "pfilt.h" |
| 16 |
|
|
| 17 |
< |
#define FTINY 1e-7 |
| 17 |
> |
#define RSCA 1.13 /* square-radius multiplier: sqrt(4/PI) */ |
| 18 |
> |
#define TEPS 0.2 /* threshold proximity goal */ |
| 19 |
> |
#define REPS 0.1 /* radius proximity goal */ |
| 20 |
|
|
| 21 |
– |
extern double rad; /* output pixel radius for filtering */ |
| 22 |
– |
|
| 23 |
– |
extern int nrows; /* number of rows for output */ |
| 24 |
– |
extern int ncols; /* number of columns for output */ |
| 25 |
– |
|
| 26 |
– |
extern int boxfilt; /* do box filtering? */ |
| 27 |
– |
|
| 28 |
– |
extern int xres, yres; /* resolution of input */ |
| 29 |
– |
|
| 30 |
– |
extern double x_c, y_r; /* conversion factors */ |
| 31 |
– |
|
| 32 |
– |
extern int xrad; /* x window size */ |
| 33 |
– |
extern int yrad; /* y window size */ |
| 34 |
– |
|
| 35 |
– |
extern int barsize; /* size of input scan bar */ |
| 36 |
– |
extern COLOR **scanin; /* input scan bar */ |
| 37 |
– |
extern COLOR *scanout; /* output scan line */ |
| 38 |
– |
|
| 39 |
– |
extern char *progname; |
| 40 |
– |
|
| 21 |
|
float *gausstable; /* gauss lookup table */ |
| 22 |
|
|
| 23 |
+ |
float *ringsum; /* sum of ring values */ |
| 24 |
+ |
short *ringwt; /* weight (count) of ring values */ |
| 25 |
+ |
short *ringndx; /* ring index table */ |
| 26 |
+ |
float *warr; /* array of pixel weights */ |
| 27 |
+ |
|
| 28 |
|
#define lookgauss(x) gausstable[(int)(10.*(x)+.5)] |
| 29 |
|
|
| 30 |
+ |
static double pickfilt(double p0); |
| 31 |
+ |
static void sumans(int px, int py, int rcent, int ccent, double m); |
| 32 |
|
|
| 33 |
< |
initmask() /* initialize gaussian lookup table */ |
| 33 |
> |
|
| 34 |
> |
extern void |
| 35 |
> |
initmask(void) /* initialize gaussian lookup table */ |
| 36 |
|
{ |
| 37 |
< |
extern char *malloc(); |
| 37 |
> |
int gtabsiz; |
| 38 |
> |
double gaussN; |
| 39 |
|
double d; |
| 40 |
|
register int x; |
| 41 |
|
|
| 42 |
< |
gausstable = (float *)malloc(100*sizeof(float)); |
| 43 |
< |
if (gausstable == NULL) { |
| 44 |
< |
fprintf(stderr, "%s: out of memory in initmask\n", progname); |
| 45 |
< |
quit(1); |
| 46 |
< |
} |
| 47 |
< |
d = x_c*y_r*0.25/rad/rad; |
| 48 |
< |
gausstable[0] = exp(-d)/sqrt(d); |
| 49 |
< |
for (x = 1; x < 100; x++) |
| 60 |
< |
if ((gausstable[x] = exp(-x*0.1)/sqrt(x*0.1)) > gausstable[0]) |
| 42 |
> |
gtabsiz = 111*CHECKRAD*CHECKRAD; |
| 43 |
> |
gausstable = (float *)malloc(gtabsiz*sizeof(float)); |
| 44 |
> |
if (gausstable == NULL) |
| 45 |
> |
goto memerr; |
| 46 |
> |
d = x_c*y_r*0.25/(rad*rad); |
| 47 |
> |
gausstable[0] = exp(-d); |
| 48 |
> |
for (x = 1; x < gtabsiz; x++) |
| 49 |
> |
if (x*0.1 <= d) |
| 50 |
|
gausstable[x] = gausstable[0]; |
| 51 |
+ |
else |
| 52 |
+ |
gausstable[x] = exp(-x*0.1); |
| 53 |
+ |
if (obarsize == 0) |
| 54 |
+ |
return; |
| 55 |
+ |
/* compute integral of filter */ |
| 56 |
+ |
gaussN = PI*d*exp(-d); /* plateau */ |
| 57 |
+ |
for (d = sqrt(d)+0.05; d <= RSCA*CHECKRAD; d += 0.1) |
| 58 |
+ |
gaussN += 0.1*2.0*PI*d*exp(-d*d); |
| 59 |
+ |
/* normalize filter */ |
| 60 |
+ |
gaussN = x_c*y_r/(rad*rad*gaussN); |
| 61 |
+ |
for (x = 0; x < gtabsiz; x++) |
| 62 |
+ |
gausstable[x] *= gaussN; |
| 63 |
+ |
/* create ring averages table */ |
| 64 |
+ |
ringndx = (short *)malloc((2*orad*orad+1)*sizeof(short)); |
| 65 |
+ |
if (ringndx == NULL) |
| 66 |
+ |
goto memerr; |
| 67 |
+ |
for (x = 2*orad*orad+1; --x > orad*orad; ) |
| 68 |
+ |
ringndx[x] = -1; |
| 69 |
+ |
do |
| 70 |
+ |
ringndx[x] = sqrt((double)x); |
| 71 |
+ |
while (x--); |
| 72 |
+ |
ringsum = (float *)malloc((orad+1)*sizeof(float)); |
| 73 |
+ |
ringwt = (short *)malloc((orad+1)*sizeof(short)); |
| 74 |
+ |
warr = (float *)malloc(obarsize*obarsize*sizeof(float)); |
| 75 |
+ |
if ((ringsum == NULL) | (ringwt == 0) | (warr == NULL)) |
| 76 |
+ |
goto memerr; |
| 77 |
+ |
return; |
| 78 |
+ |
memerr: |
| 79 |
+ |
fprintf(stderr, "%s: out of memory in initmask\n", progname); |
| 80 |
+ |
quit(1); |
| 81 |
|
} |
| 82 |
|
|
| 83 |
|
|
| 84 |
< |
dobox(csum, xcent, ycent, c, r) /* simple box filter */ |
| 85 |
< |
COLOR csum; |
| 86 |
< |
int xcent, ycent; |
| 87 |
< |
int c, r; |
| 84 |
> |
extern void |
| 85 |
> |
dobox( /* simple box filter */ |
| 86 |
> |
COLOR csum, |
| 87 |
> |
int xcent, |
| 88 |
> |
int ycent, |
| 89 |
> |
int c, |
| 90 |
> |
int r |
| 91 |
> |
) |
| 92 |
|
{ |
| 93 |
|
int wsum; |
| 94 |
|
double d; |
| 95 |
|
int y; |
| 96 |
< |
register int x; |
| 96 |
> |
register int x, offs; |
| 97 |
|
register COLOR *scan; |
| 98 |
< |
|
| 98 |
> |
|
| 99 |
|
wsum = 0; |
| 100 |
|
setcolor(csum, 0.0, 0.0, 0.0); |
| 101 |
< |
for (y = ycent+1-yrad; y <= ycent+yrad; y++) { |
| 101 |
> |
for (y = ycent+1-ybrad; y <= ycent+ybrad; y++) { |
| 102 |
|
if (y < 0) continue; |
| 103 |
|
if (y >= yres) break; |
| 104 |
< |
d = y_r < 1.0 ? y_r*y - r : (double)(y - ycent); |
| 105 |
< |
if (d > 0.5+FTINY || d < -0.5-FTINY) |
| 106 |
< |
continue; |
| 104 |
> |
d = y_r < 1.0 ? y_r*y - (r+.5) : (double)(y - ycent); |
| 105 |
> |
if (d < -0.5) continue; |
| 106 |
> |
if (d >= 0.5) break; |
| 107 |
|
scan = scanin[y%barsize]; |
| 108 |
< |
for (x = xcent+1-xrad; x <= xcent+xrad; x++) { |
| 109 |
< |
if (x < 0) continue; |
| 110 |
< |
if (x >= xres) break; |
| 88 |
< |
d = x_c < 1.0 ? x_c*x - c : (double)(x - xcent); |
| 89 |
< |
if (d > 0.5+FTINY || d < -0.5-FTINY) |
| 108 |
> |
for (x = xcent+1-xbrad; x <= xcent+xbrad; x++) { |
| 109 |
> |
offs = x < 0 ? xres : x >= xres ? -xres : 0; |
| 110 |
> |
if (offs && !wrapfilt) |
| 111 |
|
continue; |
| 112 |
+ |
d = x_c < 1.0 ? x_c*x - (c+.5) : (double)(x - xcent); |
| 113 |
+ |
if (d < -0.5) continue; |
| 114 |
+ |
if (d >= 0.5) break; |
| 115 |
|
wsum++; |
| 116 |
< |
addcolor(csum, scan[x]); |
| 116 |
> |
addcolor(csum, scan[x+offs]); |
| 117 |
|
} |
| 118 |
|
} |
| 119 |
< |
if (wsum > 1) |
| 120 |
< |
scalecolor(csum, 1.0/wsum); |
| 119 |
> |
if (wsum > 1) { |
| 120 |
> |
d = 1.0/wsum; |
| 121 |
> |
scalecolor(csum, d); |
| 122 |
> |
} |
| 123 |
|
} |
| 124 |
|
|
| 125 |
|
|
| 126 |
< |
dogauss(csum, xcent, ycent, c, r) /* gaussian filter */ |
| 127 |
< |
COLOR csum; |
| 128 |
< |
int xcent, ycent; |
| 129 |
< |
int c, r; |
| 126 |
> |
extern void |
| 127 |
> |
dogauss( /* gaussian filter */ |
| 128 |
> |
COLOR csum, |
| 129 |
> |
int xcent, |
| 130 |
> |
int ycent, |
| 131 |
> |
int c, |
| 132 |
> |
int r |
| 133 |
> |
) |
| 134 |
|
{ |
| 135 |
|
double dy, dx, weight, wsum; |
| 136 |
|
COLOR ctmp; |
| 137 |
|
int y; |
| 138 |
< |
register int x; |
| 138 |
> |
register int x, offs; |
| 139 |
|
register COLOR *scan; |
| 140 |
|
|
| 141 |
|
wsum = FTINY; |
| 146 |
|
dy = (y_r*(y+.5) - (r+.5))/rad; |
| 147 |
|
scan = scanin[y%barsize]; |
| 148 |
|
for (x = xcent-xrad; x <= xcent+xrad; x++) { |
| 149 |
< |
if (x < 0) continue; |
| 150 |
< |
if (x >= xres) break; |
| 149 |
> |
offs = x < 0 ? xres : x >= xres ? -xres : 0; |
| 150 |
> |
if (offs && !wrapfilt) |
| 151 |
> |
continue; |
| 152 |
|
dx = (x_c*(x+.5) - (c+.5))/rad; |
| 153 |
|
weight = lookgauss(dx*dx + dy*dy); |
| 154 |
|
wsum += weight; |
| 155 |
< |
copycolor(ctmp, scan[x]); |
| 155 |
> |
copycolor(ctmp, scan[x+offs]); |
| 156 |
|
scalecolor(ctmp, weight); |
| 157 |
|
addcolor(csum, ctmp); |
| 158 |
|
} |
| 159 |
|
} |
| 160 |
< |
scalecolor(csum, 1.0/wsum); |
| 160 |
> |
weight = 1.0/wsum; |
| 161 |
> |
scalecolor(csum, weight); |
| 162 |
> |
} |
| 163 |
> |
|
| 164 |
> |
|
| 165 |
> |
extern void |
| 166 |
> |
dothresh( /* gaussian threshold filter */ |
| 167 |
> |
int xcent, |
| 168 |
> |
int ycent, |
| 169 |
> |
int ccent, |
| 170 |
> |
int rcent |
| 171 |
> |
) |
| 172 |
> |
{ |
| 173 |
> |
double d; |
| 174 |
> |
int r, y, offs; |
| 175 |
> |
register int c, x; |
| 176 |
> |
register float *gscan; |
| 177 |
> |
/* compute ring sums */ |
| 178 |
> |
memset((char *)ringsum, '\0', (orad+1)*sizeof(float)); |
| 179 |
> |
memset((char *)ringwt, '\0', (orad+1)*sizeof(short)); |
| 180 |
> |
for (r = -orad; r <= orad; r++) { |
| 181 |
> |
if (rcent+r < 0) continue; |
| 182 |
> |
if (rcent+r >= nrows) break; |
| 183 |
> |
gscan = greybar[(rcent+r)%obarsize]; |
| 184 |
> |
for (c = -orad; c <= orad; c++) { |
| 185 |
> |
offs = ccent+c < 0 ? ncols : |
| 186 |
> |
ccent+c >= ncols ? -ncols : 0; |
| 187 |
> |
if (offs && !wrapfilt) |
| 188 |
> |
continue; |
| 189 |
> |
x = ringndx[c*c + r*r]; |
| 190 |
> |
if (x < 0) continue; |
| 191 |
> |
ringsum[x] += gscan[ccent+c+offs]; |
| 192 |
> |
ringwt[x]++; |
| 193 |
> |
} |
| 194 |
> |
} |
| 195 |
> |
/* filter each subpixel */ |
| 196 |
> |
for (y = ycent+1-ybrad; y <= ycent+ybrad; y++) { |
| 197 |
> |
if (y < 0) continue; |
| 198 |
> |
if (y >= yres) break; |
| 199 |
> |
d = y_r < 1.0 ? y_r*y - (rcent+.5) : (double)(y - ycent); |
| 200 |
> |
if (d < -0.5) continue; |
| 201 |
> |
if (d >= 0.5) break; |
| 202 |
> |
for (x = xcent+1-xbrad; x <= xcent+xbrad; x++) { |
| 203 |
> |
offs = x < 0 ? xres : x >= xres ? -xres : 0; |
| 204 |
> |
if (offs && !wrapfilt) |
| 205 |
> |
continue; |
| 206 |
> |
d = x_c < 1.0 ? x_c*x - (ccent+.5) : (double)(x - xcent); |
| 207 |
> |
if (d < -0.5) continue; |
| 208 |
> |
if (d >= 0.5) break; |
| 209 |
> |
sumans(x, y, rcent, ccent, |
| 210 |
> |
pickfilt((*ourbright)(scanin[y%barsize][x+offs]))); |
| 211 |
> |
} |
| 212 |
> |
} |
| 213 |
> |
} |
| 214 |
> |
|
| 215 |
> |
|
| 216 |
> |
static double |
| 217 |
> |
pickfilt( /* find filter multiplier for p0 */ |
| 218 |
> |
double p0 |
| 219 |
> |
) |
| 220 |
> |
{ |
| 221 |
> |
double m = 1.0; |
| 222 |
> |
double t, num, denom, avg, wsum; |
| 223 |
> |
double mlimit[2]; |
| 224 |
> |
int ilimit = 4.0/TEPS; |
| 225 |
> |
register int i; |
| 226 |
> |
/* iterative search for m */ |
| 227 |
> |
mlimit[0] = 1.0; mlimit[1] = orad/rad/CHECKRAD; |
| 228 |
> |
do { |
| 229 |
> |
/* compute grey weighted average */ |
| 230 |
> |
i = RSCA*CHECKRAD*rad*m + .5; |
| 231 |
> |
if (i > orad) i = orad; |
| 232 |
> |
avg = wsum = 0.0; |
| 233 |
> |
while (i--) { |
| 234 |
> |
t = (i+.5)/(m*rad); |
| 235 |
> |
t = lookgauss(t*t); |
| 236 |
> |
avg += t*ringsum[i]; |
| 237 |
> |
wsum += t*ringwt[i]; |
| 238 |
> |
} |
| 239 |
> |
if (avg < 1e-20) /* zero inclusive average */ |
| 240 |
> |
return(1.0); |
| 241 |
> |
avg /= wsum; |
| 242 |
> |
/* check threshold */ |
| 243 |
> |
denom = m*m/gausstable[0] - p0/avg; |
| 244 |
> |
if (denom <= FTINY) { /* zero exclusive average */ |
| 245 |
> |
if (m >= mlimit[1]-REPS) |
| 246 |
> |
break; |
| 247 |
> |
m = mlimit[1]; |
| 248 |
> |
continue; |
| 249 |
> |
} |
| 250 |
> |
num = p0/avg - 1.0; |
| 251 |
> |
if (num < 0.0) num = -num; |
| 252 |
> |
t = num/denom; |
| 253 |
> |
if (t <= thresh) { |
| 254 |
> |
if (m <= mlimit[0]+REPS || (thresh-t)/thresh <= TEPS) |
| 255 |
> |
break; |
| 256 |
> |
} else { |
| 257 |
> |
if (m >= mlimit[1]-REPS || (t-thresh)/thresh <= TEPS) |
| 258 |
> |
break; |
| 259 |
> |
} |
| 260 |
> |
t = m; /* remember current m */ |
| 261 |
> |
/* next guesstimate */ |
| 262 |
> |
m = sqrt(gausstable[0]*(num/thresh + p0/avg)); |
| 263 |
> |
if (m < t) { /* bound it */ |
| 264 |
> |
if (m <= mlimit[0]+FTINY) |
| 265 |
> |
m = 0.5*(mlimit[0] + t); |
| 266 |
> |
mlimit[1] = t; |
| 267 |
> |
} else { |
| 268 |
> |
if (m >= mlimit[1]-FTINY) |
| 269 |
> |
m = 0.5*(mlimit[1] + t); |
| 270 |
> |
mlimit[0] = t; |
| 271 |
> |
} |
| 272 |
> |
} while (--ilimit > 0); |
| 273 |
> |
return(m); |
| 274 |
> |
} |
| 275 |
> |
|
| 276 |
> |
|
| 277 |
> |
static void |
| 278 |
> |
sumans( /* sum input pixel to output */ |
| 279 |
> |
int px, |
| 280 |
> |
int py, |
| 281 |
> |
int rcent, |
| 282 |
> |
int ccent, |
| 283 |
> |
double m |
| 284 |
> |
) |
| 285 |
> |
{ |
| 286 |
> |
double dy2, dx; |
| 287 |
> |
COLOR pval, ctmp; |
| 288 |
> |
int ksiz, r, offs; |
| 289 |
> |
double pc, pr, norm; |
| 290 |
> |
register int i, c; |
| 291 |
> |
register COLOR *scan; |
| 292 |
> |
/* |
| 293 |
> |
* This normalization method fails at the picture borders because |
| 294 |
> |
* a different number of input pixels contribute there. |
| 295 |
> |
*/ |
| 296 |
> |
scan = scanin[py%barsize] + (px < 0 ? xres : px >= xres ? -xres : 0); |
| 297 |
> |
copycolor(pval, scan[px]); |
| 298 |
> |
pc = x_c*(px+.5); |
| 299 |
> |
pr = y_r*(py+.5); |
| 300 |
> |
ksiz = CHECKRAD*m*rad + 1; |
| 301 |
> |
if (ksiz > orad) ksiz = orad; |
| 302 |
> |
/* compute normalization */ |
| 303 |
> |
norm = 0.0; |
| 304 |
> |
i = 0; |
| 305 |
> |
for (r = rcent-ksiz; r <= rcent+ksiz; r++) { |
| 306 |
> |
if (r < 0) continue; |
| 307 |
> |
if (r >= nrows) break; |
| 308 |
> |
dy2 = (pr - (r+.5))/(m*rad); |
| 309 |
> |
dy2 *= dy2; |
| 310 |
> |
for (c = ccent-ksiz; c <= ccent+ksiz; c++) { |
| 311 |
> |
if (!wrapfilt) { |
| 312 |
> |
if (c < 0) continue; |
| 313 |
> |
if (c >= ncols) break; |
| 314 |
> |
} |
| 315 |
> |
dx = (pc - (c+.5))/(m*rad); |
| 316 |
> |
norm += warr[i++] = lookgauss(dx*dx + dy2); |
| 317 |
> |
} |
| 318 |
> |
} |
| 319 |
> |
norm = 1.0/norm; |
| 320 |
> |
if (x_c < 1.0) norm *= x_c; |
| 321 |
> |
if (y_r < 1.0) norm *= y_r; |
| 322 |
> |
/* sum pixels */ |
| 323 |
> |
i = 0; |
| 324 |
> |
for (r = rcent-ksiz; r <= rcent+ksiz; r++) { |
| 325 |
> |
if (r < 0) continue; |
| 326 |
> |
if (r >= nrows) break; |
| 327 |
> |
scan = scoutbar[r%obarsize]; |
| 328 |
> |
for (c = ccent-ksiz; c <= ccent+ksiz; c++) { |
| 329 |
> |
offs = c < 0 ? ncols : c >= ncols ? -ncols : 0; |
| 330 |
> |
if (offs && !wrapfilt) |
| 331 |
> |
continue; |
| 332 |
> |
copycolor(ctmp, pval); |
| 333 |
> |
dx = norm*warr[i++]; |
| 334 |
> |
scalecolor(ctmp, dx); |
| 335 |
> |
addcolor(scan[c+offs], ctmp); |
| 336 |
> |
} |
| 337 |
> |
} |
| 338 |
|
} |
