src/px/pf3.c

/* Copyright (c) 1992 Regents of the University of California */

#ifndef lint
static char SCCSid[] = "$SunId$ LBL";
#endif

/*
 *  pf3.c - routines for gaussian and box filtering
 *
 *     8/13/86
 */

#include  <stdio.h>

#include  <math.h>

#include  "color.h"

#define  FTINY          1e-7

extern double  rad;             /* output pixel radius for filtering */

extern int  nrows;              /* number of rows for output */
extern int  ncols;              /* number of columns for output */

extern int  boxfilt;            /* do box filtering? */

extern int  xres, yres;         /* resolution of input */

extern double  x_c, y_r;        /* conversion factors */

extern int  xrad;               /* x window size */
extern int  yrad;               /* y window size */

extern int  barsize;            /* size of input scan bar */
extern COLOR  **scanin;         /* input scan bar */
extern COLOR  *scanout;         /* output scan line */

extern char  *progname;

float  *exptable;               /* exponent table */

#define  lookexp(x)             exptable[(int)(-10.*(x)+.5)]


initmask()                      /* initialize gaussian lookup table */
{
        extern char  *malloc();
        register int  x;

        exptable = (float *)malloc(100*sizeof(float));
        if (exptable == NULL) {
                fprintf(stderr, "%s: out of memory in initmask\n", progname);
                quit(1);
        }
        for (x = 0; x < 100; x++)
                exptable[x] = exp(-x*0.1);
}


dobox(csum, xcent, ycent, c, r)                 /* simple box filter */
COLOR  csum;
int  xcent, ycent;
int  c, r;
{
        static int  wsum;
        static double  d;
        static int  y;
        register int  x;
        register COLOR  *scan;

        wsum = 0;
        setcolor(csum, 0.0, 0.0, 0.0);
        for (y = ycent+1-yrad; y <= ycent+yrad; y++) {
                if (y < 0 || y >= yres)
                        continue;
                d = y_r < 1.0 ? y_r*y - r : y - ycent;
                if (d > 0.5+FTINY || d < -0.5-FTINY)
                        continue;
                scan = scanin[y%barsize];
                for (x = xcent+1-xrad; x <= xcent+xrad; x++) {
                        if (x < 0 || x >= xres)
                                continue;
                        d = x_c < 1.0 ? x_c*x - c : x - xcent;
                        if (d > 0.5+FTINY || d < -0.5-FTINY)
                                continue;
                        wsum++;
                        addcolor(csum, scan[x]);
                }
        }
        if (wsum > 1)
                scalecolor(csum, 1.0/wsum);
}


dogauss(csum, xcent, ycent, c, r)               /* gaussian filter */
COLOR  csum;
int  xcent, ycent;
int  c, r;
{
        static double  dy, dx, weight, wsum;
        static COLOR  ctmp;
        static int  y;
        register int  x;
        register COLOR  *scan;

        wsum = FTINY;
        setcolor(csum, 0.0, 0.0, 0.0);
        for (y = ycent-yrad; y <= ycent+yrad; y++) {
                if (y < 0 || y >= yres)
                        continue;
                dy = (y_r*(y+.5) - (r+.5))/rad;
                scan = scanin[y%barsize];
                for (x = xcent-xrad; x <= xcent+xrad; x++) {
                        if (x < 0 || x >= xres)
                                continue;
                        dx = (x_c*(x+.5) - (c+.5))/rad;
                        weight = lookexp(-(dx*dx + dy*dy));
                        wsum += weight;
                        copycolor(ctmp, scan[x]);
                        scalecolor(ctmp, weight);
                        addcolor(csum, ctmp);
                }
        }
        scalecolor(csum, 1.0/wsum);
}
Revision:	2.3
Committed:	Fri Oct 2 16:23:41 1992 UTC (31 years, 7 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 2.2:	+2 -1 lines
Log Message:	Removed problematic math function declarations
#	User	Rev	Content
1	greg	2.2	/* Copyright (c) 1992 Regents of the University of California */
2	greg	1.1
3			#ifndef lint
4			static char SCCSid[] = "$SunId$ LBL";
5			#endif
6
7			/*
8			* pf3.c - routines for gaussian and box filtering
9			*
10			* 8/13/86
11			*/
12
13			#include <stdio.h>
14
15	greg	2.3	#include <math.h>
16
17	greg	1.1	#include "color.h"
18
19	greg	2.2	#define FTINY 1e-7
20	greg	1.1
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
41			float exptable; / exponent table */
42
43	greg	2.2	#define lookexp(x) exptable[(int)(-10.*(x)+.5)]
44	greg	1.1
45
46			initmask() /* initialize gaussian lookup table */
47			{
48			extern char *malloc();
49			register int x;
50
51			exptable = (float )malloc(100sizeof(float));
52			if (exptable == NULL) {
53			fprintf(stderr, "%s: out of memory in initmask\n", progname);
54			quit(1);
55			}
56			for (x = 0; x < 100; x++)
57			exptable[x] = exp(-x*0.1);
58			}
59
60
61			dobox(csum, xcent, ycent, c, r) /* simple box filter */
62			COLOR csum;
63			int xcent, ycent;
64			int c, r;
65			{
66			static int wsum;
67			static double d;
68			static int y;
69			register int x;
70	greg	2.2	register COLOR *scan;
71	greg	1.1
72			wsum = 0;
73			setcolor(csum, 0.0, 0.0, 0.0);
74			for (y = ycent+1-yrad; y <= ycent+yrad; y++) {
75			if (y < 0 \|\| y >= yres)
76			continue;
77			d = y_r < 1.0 ? y_r*y - r : y - ycent;
78			if (d > 0.5+FTINY \|\| d < -0.5-FTINY)
79			continue;
80			scan = scanin[y%barsize];
81			for (x = xcent+1-xrad; x <= xcent+xrad; x++) {
82			if (x < 0 \|\| x >= xres)
83			continue;
84			d = x_c < 1.0 ? x_c*x - c : x - xcent;
85			if (d > 0.5+FTINY \|\| d < -0.5-FTINY)
86			continue;
87			wsum++;
88			addcolor(csum, scan[x]);
89			}
90			}
91			if (wsum > 1)
92			scalecolor(csum, 1.0/wsum);
93			}
94
95
96			dogauss(csum, xcent, ycent, c, r) /* gaussian filter */
97			COLOR csum;
98			int xcent, ycent;
99			int c, r;
100			{
101			static double dy, dx, weight, wsum;
102			static COLOR ctmp;
103			static int y;
104			register int x;
105	greg	2.2	register COLOR *scan;
106	greg	1.1
107			wsum = FTINY;
108			setcolor(csum, 0.0, 0.0, 0.0);
109	greg	1.2	for (y = ycent-yrad; y <= ycent+yrad; y++) {
110	greg	1.1	if (y < 0 \|\| y >= yres)
111			continue;
112	greg	1.2	dy = (y_r*(y+.5) - (r+.5))/rad;
113	greg	1.1	scan = scanin[y%barsize];
114	greg	1.2	for (x = xcent-xrad; x <= xcent+xrad; x++) {
115	greg	1.1	if (x < 0 \|\| x >= xres)
116			continue;
117	greg	1.2	dx = (x_c*(x+.5) - (c+.5))/rad;
118	greg	1.1	weight = lookexp(-(dxdx + dydy));
119			wsum += weight;
120			copycolor(ctmp, scan[x]);
121			scalecolor(ctmp, weight);
122			addcolor(csum, ctmp);
123			}
124			}
125			scalecolor(csum, 1.0/wsum);
126			}