| 1 |
#ifndef lint
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| 2 |
static const char RCSid[] = "$Id: ra_ppm.c,v 2.18 2025/06/06 19:11:21 greg Exp $";
|
| 3 |
#endif
|
| 4 |
/*
|
| 5 |
* program to convert between RADIANCE and Poskanzer Pixmaps
|
| 6 |
*/
|
| 7 |
|
| 8 |
#include <math.h>
|
| 9 |
#include <ctype.h>
|
| 10 |
#include "platform.h"
|
| 11 |
#include "rtio.h"
|
| 12 |
#include "color.h"
|
| 13 |
#include "resolu.h"
|
| 14 |
|
| 15 |
#define fltv(i) (((i)+.5)/(maxval+1.))
|
| 16 |
int bradj = 0; /* brightness adjustment */
|
| 17 |
double gamcor = 2.2; /* gamma correction value */
|
| 18 |
int maxval = 255; /* maximum primary value */
|
| 19 |
int xmax, ymax;
|
| 20 |
|
| 21 |
typedef int colrscanf_t(COLR *scan, int len, FILE *fp);
|
| 22 |
typedef int colorscanf_t(COLOR *scan, int len, FILE *fp);
|
| 23 |
|
| 24 |
static colrscanf_t agryscan, bgryscan, aclrscan, bclrscan;
|
| 25 |
static void ppm2ra(colrscanf_t *getscan);
|
| 26 |
static void ra2ppm(int binary, int grey);
|
| 27 |
|
| 28 |
static colorscanf_t agryscan2, bgryscan2, aclrscan2, bclrscan2;
|
| 29 |
static void ppm2ra2(colorscanf_t *getscan);
|
| 30 |
static void ra2ppm2(int binary, int grey);
|
| 31 |
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| 32 |
static int normval(unsigned int v);
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| 33 |
static unsigned int scanint(FILE *fp);
|
| 34 |
static unsigned int intv(double v);
|
| 35 |
static unsigned int getby2(FILE *fp);
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| 36 |
static void putby2(unsigned int w, FILE *fp);
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| 37 |
static void quiterr(char *err);
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| 38 |
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| 39 |
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| 40 |
int
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| 41 |
main(
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| 42 |
int argc,
|
| 43 |
char *argv[]
|
| 44 |
)
|
| 45 |
{
|
| 46 |
char inpbuf[2];
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| 47 |
int gryflag = 0;
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| 48 |
int binflag = 1;
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| 49 |
int reverse = 0;
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| 50 |
int ptype;
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| 51 |
int i;
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| 52 |
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| 53 |
fixargv0(argv[0]);
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| 54 |
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| 55 |
for (i = 1; i < argc; i++)
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| 56 |
if (argv[i][0] == '-')
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| 57 |
switch (argv[i][1]) {
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| 58 |
case 's':
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| 59 |
maxval = atoi(argv[++i]) & 0xffff;
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| 60 |
break;
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| 61 |
case 'b':
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| 62 |
gryflag = 1;
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| 63 |
break;
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| 64 |
case 'g':
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| 65 |
gamcor = atof(argv[++i]);
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| 66 |
break;
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| 67 |
case 'e':
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| 68 |
if (argv[i+1][0] != '+' && argv[i+1][0] != '-')
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| 69 |
goto userr;
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| 70 |
bradj = atoi(argv[++i]);
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| 71 |
break;
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| 72 |
case 'a':
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| 73 |
binflag = 0;
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| 74 |
break;
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| 75 |
case 'r':
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| 76 |
reverse = !reverse;
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| 77 |
break;
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| 78 |
default:
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| 79 |
goto userr;
|
| 80 |
}
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| 81 |
else
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| 82 |
break;
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| 83 |
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| 84 |
if (i < argc-2)
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| 85 |
goto userr;
|
| 86 |
if (i <= argc-1 && freopen(argv[i], "r", stdin) == NULL) {
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| 87 |
fprintf(stderr, "%s: can't open input \"%s\"\n",
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| 88 |
progname, argv[i]);
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| 89 |
exit(1);
|
| 90 |
}
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| 91 |
if (i == argc-2 && freopen(argv[i+1], "w", stdout) == NULL) {
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| 92 |
fprintf(stderr, "%s: can't open output \"%s\"\n",
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| 93 |
progname, argv[i+1]);
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| 94 |
exit(1);
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| 95 |
}
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| 96 |
if (maxval < 256)
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| 97 |
setcolrgam(gamcor);
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| 98 |
if (reverse) {
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| 99 |
/* get header */
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| 100 |
if (read(fileno(stdin), inpbuf, 2) != 2 || inpbuf[0] != 'P')
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| 101 |
quiterr("input not a Poskanzer Pixmap");
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| 102 |
ptype = inpbuf[1];
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| 103 |
#if defined(_WIN32) || defined(_WIN64)
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| 104 |
if (ptype > 4)
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| 105 |
SET_FILE_BINARY(stdin);
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| 106 |
SET_FILE_BINARY(stdout);
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| 107 |
#endif
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| 108 |
xmax = scanint(stdin);
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| 109 |
ymax = scanint(stdin);
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| 110 |
maxval = scanint(stdin);
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| 111 |
/* put header */
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| 112 |
newheader("RADIANCE", stdout);
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| 113 |
printargs(i, argv, stdout);
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| 114 |
fputformat(COLRFMT, stdout);
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| 115 |
putchar('\n');
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| 116 |
fprtresolu(xmax, ymax, stdout);
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| 117 |
/* convert file */
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| 118 |
if (maxval >= 256)
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| 119 |
switch (ptype) {
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case '2':
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| 121 |
ppm2ra2(agryscan2);
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| 122 |
break;
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| 123 |
case '5':
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| 124 |
ppm2ra2(bgryscan2);
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| 125 |
break;
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| 126 |
case '3':
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| 127 |
ppm2ra2(aclrscan2);
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| 128 |
break;
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| 129 |
case '6':
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| 130 |
ppm2ra2(bclrscan2);
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| 131 |
break;
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| 132 |
default:
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| 133 |
quiterr("unsupported Pixmap type");
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| 134 |
}
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| 135 |
else
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| 136 |
switch (ptype) {
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| 137 |
case '2':
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| 138 |
ppm2ra(agryscan);
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| 139 |
break;
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| 140 |
case '5':
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| 141 |
ppm2ra(bgryscan);
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| 142 |
break;
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| 143 |
case '3':
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| 144 |
ppm2ra(aclrscan);
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| 145 |
break;
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| 146 |
case '6':
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| 147 |
ppm2ra(bclrscan);
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| 148 |
break;
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| 149 |
default:
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| 150 |
quiterr("unsupported Pixmap type");
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| 151 |
}
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| 152 |
} else {
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| 153 |
#if defined(_WIN32) || defined(_WIN64)
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| 154 |
SET_FILE_BINARY(stdin);
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| 155 |
if (binflag)
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| 156 |
SET_FILE_BINARY(stdout);
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| 157 |
#endif
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| 158 |
/* get header info. */
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| 159 |
if (checkheader(stdin, COLRFMT, NULL) < 0 ||
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| 160 |
fgetresolu(&xmax, &ymax, stdin) < 0)
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| 161 |
quiterr("bad picture format");
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| 162 |
/* write PPM header */
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| 163 |
printf("P%1d\n%d %d\n%u\n", (gryflag?2:3)+(binflag?3:0),
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| 164 |
xmax, ymax, maxval);
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| 165 |
/* convert file */
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| 166 |
if (maxval >= 256)
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| 167 |
ra2ppm2(binflag, gryflag);
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| 168 |
else
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| 169 |
ra2ppm(binflag, gryflag);
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| 170 |
}
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| 171 |
exit(0);
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| 172 |
userr:
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| 173 |
fprintf(stderr,
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| 174 |
"Usage: %s [-r][-a][-b][-s maxv][-g gamma][-e +/-stops] [input [output]]\n",
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| 175 |
progname);
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| 176 |
exit(1);
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| 177 |
}
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| 178 |
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| 179 |
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| 180 |
static void
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| 181 |
quiterr( /* print message and exit */
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| 182 |
char *err
|
| 183 |
)
|
| 184 |
{
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| 185 |
if (err != NULL) {
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| 186 |
fprintf(stderr, "%s: %s\n", progname, err);
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| 187 |
exit(1);
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| 188 |
}
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| 189 |
exit(0);
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| 190 |
}
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| 191 |
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| 192 |
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| 193 |
static void
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| 194 |
ppm2ra( /* convert 1-byte Pixmap to Radiance picture */
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| 195 |
colrscanf_t *getscan
|
| 196 |
)
|
| 197 |
{
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| 198 |
COLR *scanout;
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| 199 |
int y;
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| 200 |
/* allocate scanline */
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| 201 |
scanout = (COLR *)malloc(xmax*sizeof(COLR));
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| 202 |
if (scanout == NULL)
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| 203 |
quiterr("out of memory in ppm2ra");
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| 204 |
/* convert image */
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| 205 |
for (y = ymax-1; y >= 0; y--) {
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| 206 |
if ((*getscan)(scanout, xmax, stdin) < 0)
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| 207 |
quiterr("error reading Pixmap");
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| 208 |
gambs_colrs(scanout, xmax);
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| 209 |
if (bradj)
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| 210 |
shiftcolrs(scanout, xmax, bradj);
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| 211 |
if (fwritecolrs(scanout, xmax, stdout) < 0)
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| 212 |
quiterr("error writing Radiance picture");
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}
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| 214 |
/* free scanline */
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| 215 |
free((void *)scanout);
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| 216 |
}
|
| 217 |
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| 218 |
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| 219 |
static void
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ra2ppm( /* convert Radiance picture to 1-byte/sample Pixmap */
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| 221 |
int binary,
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| 222 |
int grey
|
| 223 |
)
|
| 224 |
{
|
| 225 |
COLR *scanin;
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| 226 |
register int x;
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| 227 |
int y;
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| 228 |
/* allocate scanline */
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| 229 |
scanin = (COLR *)malloc(xmax*sizeof(COLR));
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| 230 |
if (scanin == NULL)
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| 231 |
quiterr("out of memory in ra2ppm");
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| 232 |
/* convert image */
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| 233 |
for (y = ymax-1; y >= 0; y--) {
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| 234 |
if (freadcolrs(scanin, xmax, stdin) < 0)
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| 235 |
quiterr("error reading Radiance picture");
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| 236 |
if (bradj)
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| 237 |
shiftcolrs(scanin, xmax, bradj);
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| 238 |
for (x = grey?xmax:0; x--; )
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| 239 |
scanin[x][GRN] = normbright(scanin[x]);
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| 240 |
colrs_gambs(scanin, xmax);
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| 241 |
if (grey)
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| 242 |
if (binary)
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| 243 |
for (x = 0; x < xmax; x++)
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| 244 |
putc(scanin[x][GRN], stdout);
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| 245 |
else
|
| 246 |
for (x = 0; x < xmax; x++)
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| 247 |
printf("%d\n", scanin[x][GRN]);
|
| 248 |
else
|
| 249 |
if (binary)
|
| 250 |
for (x = 0; x < xmax; x++) {
|
| 251 |
putc(scanin[x][RED], stdout);
|
| 252 |
putc(scanin[x][GRN], stdout);
|
| 253 |
putc(scanin[x][BLU], stdout);
|
| 254 |
}
|
| 255 |
else
|
| 256 |
for (x = 0; x < xmax; x++)
|
| 257 |
printf("%d %d %d\n", scanin[x][RED],
|
| 258 |
scanin[x][GRN],
|
| 259 |
scanin[x][BLU]);
|
| 260 |
if (ferror(stdout))
|
| 261 |
quiterr("error writing Pixmap");
|
| 262 |
}
|
| 263 |
/* free scanline */
|
| 264 |
free((void *)scanin);
|
| 265 |
}
|
| 266 |
|
| 267 |
|
| 268 |
static void
|
| 269 |
ppm2ra2( /* convert 2-byte Pixmap to Radiance picture */
|
| 270 |
colorscanf_t *getscan
|
| 271 |
)
|
| 272 |
{
|
| 273 |
COLOR *scanout;
|
| 274 |
double mult;
|
| 275 |
int y;
|
| 276 |
register int x;
|
| 277 |
/* allocate scanline */
|
| 278 |
scanout = (COLOR *)malloc(xmax*sizeof(COLOR));
|
| 279 |
if (scanout == NULL)
|
| 280 |
quiterr("out of memory in ppm2ra2");
|
| 281 |
if (bradj)
|
| 282 |
mult = pow(2., (double)bradj);
|
| 283 |
/* convert image */
|
| 284 |
for (y = ymax-1; y >= 0; y--) {
|
| 285 |
if ((*getscan)(scanout, xmax, stdin) < 0)
|
| 286 |
quiterr("error reading Pixmap");
|
| 287 |
for (x = (gamcor>1.01)|(gamcor<0.99)?xmax:0; x--; ) {
|
| 288 |
colval(scanout[x],RED) =
|
| 289 |
pow(colval(scanout[x],RED), gamcor);
|
| 290 |
colval(scanout[x],GRN) =
|
| 291 |
pow(colval(scanout[x],GRN), gamcor);
|
| 292 |
colval(scanout[x],BLU) =
|
| 293 |
pow(colval(scanout[x],BLU), gamcor);
|
| 294 |
}
|
| 295 |
for (x = bradj?xmax:0; x--; )
|
| 296 |
scalecolor(scanout[x], mult);
|
| 297 |
if (fwritescan(scanout, xmax, stdout) < 0)
|
| 298 |
quiterr("error writing Radiance picture");
|
| 299 |
}
|
| 300 |
/* free scanline */
|
| 301 |
free((void *)scanout);
|
| 302 |
}
|
| 303 |
|
| 304 |
|
| 305 |
static void
|
| 306 |
ra2ppm2( /* convert Radiance picture to Pixmap (2-byte) */
|
| 307 |
int binary,
|
| 308 |
int grey
|
| 309 |
)
|
| 310 |
{
|
| 311 |
COLOR *scanin;
|
| 312 |
double mult, d;
|
| 313 |
register int x;
|
| 314 |
int y;
|
| 315 |
/* allocate scanline */
|
| 316 |
scanin = (COLOR *)malloc(xmax*sizeof(COLOR));
|
| 317 |
if (scanin == NULL)
|
| 318 |
quiterr("out of memory in ra2ppm2");
|
| 319 |
if (bradj)
|
| 320 |
mult = pow(2., (double)bradj);
|
| 321 |
/* convert image */
|
| 322 |
for (y = ymax-1; y >= 0; y--) {
|
| 323 |
if (freadscan(scanin, xmax, stdin) < 0)
|
| 324 |
quiterr("error reading Radiance picture");
|
| 325 |
for (x = bradj?xmax:0; x--; )
|
| 326 |
scalecolor(scanin[x], mult);
|
| 327 |
for (x = grey?xmax:0; x--; )
|
| 328 |
colval(scanin[x],GRN) = bright(scanin[x]);
|
| 329 |
d = 1./gamcor;
|
| 330 |
for (x = (d>1.01)|(d<0.99)?xmax:0; x--; ) {
|
| 331 |
colval(scanin[x],GRN) = pow(colval(scanin[x],GRN), d);
|
| 332 |
if (!grey) {
|
| 333 |
colval(scanin[x],RED) =
|
| 334 |
pow(colval(scanin[x],RED), d);
|
| 335 |
colval(scanin[x],BLU) =
|
| 336 |
pow(colval(scanin[x],BLU), d);
|
| 337 |
}
|
| 338 |
}
|
| 339 |
if (grey)
|
| 340 |
if (binary)
|
| 341 |
for (x = 0; x < xmax; x++)
|
| 342 |
putby2(intv(colval(scanin[x],GRN)),
|
| 343 |
stdout);
|
| 344 |
else
|
| 345 |
for (x = 0; x < xmax; x++)
|
| 346 |
printf("%u\n",
|
| 347 |
intv(colval(scanin[x],GRN)));
|
| 348 |
else
|
| 349 |
if (binary)
|
| 350 |
for (x = 0; x < xmax; x++) {
|
| 351 |
putby2(intv(colval(scanin[x],RED)),
|
| 352 |
stdout);
|
| 353 |
putby2(intv(colval(scanin[x],GRN)),
|
| 354 |
stdout);
|
| 355 |
putby2(intv(colval(scanin[x],BLU)),
|
| 356 |
stdout);
|
| 357 |
}
|
| 358 |
else
|
| 359 |
for (x = 0; x < xmax; x++)
|
| 360 |
printf("%u %u %u\n",
|
| 361 |
intv(colval(scanin[x],RED)),
|
| 362 |
intv(colval(scanin[x],GRN)),
|
| 363 |
intv(colval(scanin[x],BLU)));
|
| 364 |
if (ferror(stdout))
|
| 365 |
quiterr("error writing Pixmap");
|
| 366 |
}
|
| 367 |
/* free scanline */
|
| 368 |
free((void *)scanin);
|
| 369 |
}
|
| 370 |
|
| 371 |
|
| 372 |
static int
|
| 373 |
agryscan( /* get an ASCII greyscale scanline */
|
| 374 |
register COLR *scan,
|
| 375 |
register int len,
|
| 376 |
FILE *fp
|
| 377 |
)
|
| 378 |
{
|
| 379 |
while (len-- > 0) {
|
| 380 |
scan[0][RED] =
|
| 381 |
scan[0][GRN] =
|
| 382 |
scan[0][BLU] = normval(scanint(fp));
|
| 383 |
scan++;
|
| 384 |
}
|
| 385 |
return(0);
|
| 386 |
}
|
| 387 |
|
| 388 |
|
| 389 |
static int
|
| 390 |
bgryscan( /* get a binary greyscale scanline */
|
| 391 |
register COLR *scan,
|
| 392 |
int len,
|
| 393 |
register FILE *fp
|
| 394 |
)
|
| 395 |
{
|
| 396 |
register int c;
|
| 397 |
|
| 398 |
while (len-- > 0) {
|
| 399 |
if ((c = getc(fp)) == EOF)
|
| 400 |
return(-1);
|
| 401 |
if (maxval != 255)
|
| 402 |
c = normval(c);
|
| 403 |
scan[0][RED] =
|
| 404 |
scan[0][GRN] =
|
| 405 |
scan[0][BLU] = c;
|
| 406 |
scan++;
|
| 407 |
}
|
| 408 |
return(0);
|
| 409 |
}
|
| 410 |
|
| 411 |
|
| 412 |
static int
|
| 413 |
aclrscan( /* get an ASCII color scanline */
|
| 414 |
register COLR *scan,
|
| 415 |
register int len,
|
| 416 |
FILE *fp
|
| 417 |
)
|
| 418 |
{
|
| 419 |
while (len-- > 0) {
|
| 420 |
scan[0][RED] = normval(scanint(fp));
|
| 421 |
scan[0][GRN] = normval(scanint(fp));
|
| 422 |
scan[0][BLU] = normval(scanint(fp));
|
| 423 |
scan++;
|
| 424 |
}
|
| 425 |
return(0);
|
| 426 |
}
|
| 427 |
|
| 428 |
|
| 429 |
static int
|
| 430 |
bclrscan( /* get a binary color scanline */
|
| 431 |
register COLR *scan,
|
| 432 |
int len,
|
| 433 |
register FILE *fp
|
| 434 |
)
|
| 435 |
{
|
| 436 |
int r, g, b;
|
| 437 |
|
| 438 |
while (len-- > 0) {
|
| 439 |
r = getc(fp);
|
| 440 |
g = getc(fp);
|
| 441 |
if ((b = getc(fp)) == EOF)
|
| 442 |
return(-1);
|
| 443 |
if (maxval == 255) {
|
| 444 |
scan[0][RED] = r;
|
| 445 |
scan[0][GRN] = g;
|
| 446 |
scan[0][BLU] = b;
|
| 447 |
} else {
|
| 448 |
scan[0][RED] = normval(r);
|
| 449 |
scan[0][GRN] = normval(g);
|
| 450 |
scan[0][BLU] = normval(b);
|
| 451 |
}
|
| 452 |
scan++;
|
| 453 |
}
|
| 454 |
return(0);
|
| 455 |
}
|
| 456 |
|
| 457 |
|
| 458 |
static int
|
| 459 |
agryscan2( /* get an ASCII greyscale scanline */
|
| 460 |
register COLOR *scan,
|
| 461 |
register int len,
|
| 462 |
FILE *fp
|
| 463 |
)
|
| 464 |
{
|
| 465 |
while (len-- > 0) {
|
| 466 |
colval(scan[0],RED) =
|
| 467 |
colval(scan[0],GRN) =
|
| 468 |
colval(scan[0],BLU) = fltv(scanint(fp));
|
| 469 |
scan++;
|
| 470 |
}
|
| 471 |
return(0);
|
| 472 |
}
|
| 473 |
|
| 474 |
|
| 475 |
static int
|
| 476 |
bgryscan2( /* get a binary greyscale scanline */
|
| 477 |
register COLOR *scan,
|
| 478 |
int len,
|
| 479 |
register FILE *fp
|
| 480 |
)
|
| 481 |
{
|
| 482 |
register int c;
|
| 483 |
|
| 484 |
while (len-- > 0) {
|
| 485 |
if ((c = getby2(fp)) == EOF)
|
| 486 |
return(-1);
|
| 487 |
colval(scan[0],RED) =
|
| 488 |
colval(scan[0],GRN) =
|
| 489 |
colval(scan[0],BLU) = fltv(c);
|
| 490 |
scan++;
|
| 491 |
}
|
| 492 |
return(0);
|
| 493 |
}
|
| 494 |
|
| 495 |
|
| 496 |
static int
|
| 497 |
aclrscan2( /* get an ASCII color scanline */
|
| 498 |
register COLOR *scan,
|
| 499 |
register int len,
|
| 500 |
FILE *fp
|
| 501 |
)
|
| 502 |
{
|
| 503 |
while (len-- > 0) {
|
| 504 |
colval(scan[0],RED) = fltv(scanint(fp));
|
| 505 |
colval(scan[0],GRN) = fltv(scanint(fp));
|
| 506 |
colval(scan[0],BLU) = fltv(scanint(fp));
|
| 507 |
scan++;
|
| 508 |
}
|
| 509 |
return(0);
|
| 510 |
}
|
| 511 |
|
| 512 |
|
| 513 |
static int
|
| 514 |
bclrscan2( /* get a binary color scanline */
|
| 515 |
register COLOR *scan,
|
| 516 |
int len,
|
| 517 |
register FILE *fp
|
| 518 |
)
|
| 519 |
{
|
| 520 |
int r, g, b;
|
| 521 |
|
| 522 |
while (len-- > 0) {
|
| 523 |
r = getby2(fp);
|
| 524 |
g = getby2(fp);
|
| 525 |
if ((b = getby2(fp)) == EOF)
|
| 526 |
return(-1);
|
| 527 |
scan[0][RED] = fltv(r);
|
| 528 |
scan[0][GRN] = fltv(g);
|
| 529 |
scan[0][BLU] = fltv(b);
|
| 530 |
scan++;
|
| 531 |
}
|
| 532 |
return(0);
|
| 533 |
}
|
| 534 |
|
| 535 |
|
| 536 |
static unsigned int
|
| 537 |
scanint( /* scan the next positive integer value */
|
| 538 |
register FILE *fp
|
| 539 |
)
|
| 540 |
{
|
| 541 |
register int c;
|
| 542 |
register unsigned int i;
|
| 543 |
tryagain:
|
| 544 |
while (isspace(c = getc(fp)))
|
| 545 |
;
|
| 546 |
if (c == EOF)
|
| 547 |
quiterr("unexpected end of file");
|
| 548 |
if (c == '#') { /* comment */
|
| 549 |
while ((c = getc(fp)) != EOF && c != '\n')
|
| 550 |
;
|
| 551 |
goto tryagain;
|
| 552 |
}
|
| 553 |
/* should be integer */
|
| 554 |
i = 0;
|
| 555 |
do {
|
| 556 |
if (!isdigit(c))
|
| 557 |
quiterr("error reading integer");
|
| 558 |
i = 10*i + c - '0';
|
| 559 |
c = getc(fp);
|
| 560 |
} while (c != EOF && !isspace(c));
|
| 561 |
return(i);
|
| 562 |
}
|
| 563 |
|
| 564 |
|
| 565 |
static int
|
| 566 |
normval( /* normalize a value to [0,255] */
|
| 567 |
register unsigned int v
|
| 568 |
)
|
| 569 |
{
|
| 570 |
if (v >= maxval)
|
| 571 |
return(255);
|
| 572 |
if (maxval == 255)
|
| 573 |
return(v);
|
| 574 |
return(v*255L/maxval);
|
| 575 |
}
|
| 576 |
|
| 577 |
|
| 578 |
static unsigned int
|
| 579 |
getby2( /* return 2-byte quantity from fp */
|
| 580 |
register FILE *fp
|
| 581 |
)
|
| 582 |
{
|
| 583 |
register int lowerb, upperb;
|
| 584 |
|
| 585 |
upperb = getc(fp);
|
| 586 |
lowerb = getc(fp);
|
| 587 |
if (lowerb == EOF)
|
| 588 |
return(EOF);
|
| 589 |
return(upperb<<8 | lowerb);
|
| 590 |
}
|
| 591 |
|
| 592 |
|
| 593 |
static void
|
| 594 |
putby2( /* put 2-byte quantity to fp */
|
| 595 |
register unsigned int w,
|
| 596 |
register FILE *fp
|
| 597 |
)
|
| 598 |
{
|
| 599 |
putc(w>>8 & 0xff, fp);
|
| 600 |
putc(w & 0xff, fp);
|
| 601 |
if (ferror(fp)) {
|
| 602 |
fprintf(stderr, "%s: write error on PPM output\n", progname);
|
| 603 |
exit(1);
|
| 604 |
}
|
| 605 |
}
|
| 606 |
|
| 607 |
|
| 608 |
static unsigned int
|
| 609 |
intv( /* return integer quantity for v */
|
| 610 |
register double v
|
| 611 |
)
|
| 612 |
{
|
| 613 |
if (v >= 0.99999)
|
| 614 |
return(maxval);
|
| 615 |
if (v <= 0.)
|
| 616 |
return(0);
|
| 617 |
return((int)(v*(maxval+1)));
|
| 618 |
}
|
