1 |
greg |
2.1 |
/* Copyright (c) 1994 Regents of the University of California */ |
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#ifndef lint |
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static char SCCSid[] = "$SunId$ LBL"; |
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#endif |
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7 |
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/* |
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* Convert from Radiance picture file to Compuserve GIF. |
9 |
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* Currently, we don't know how to get back. |
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*/ |
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#include <stdio.h> |
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#include "color.h" |
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#include "resolu.h" |
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18 |
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#ifdef MSDOS |
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#include <fcntl.h> |
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#endif |
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#include <math.h> |
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24 |
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#define MAXCOLORS 256 |
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26 |
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int rmap[MAXCOLORS]; |
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int gmap[MAXCOLORS]; |
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int bmap[MAXCOLORS]; |
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30 |
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int currow; |
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32 |
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extern long ftell(); |
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34 |
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long picstart; |
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36 |
greg |
2.4 |
BYTE clrtab[256][3]; |
37 |
greg |
2.1 |
|
38 |
greg |
2.4 |
extern int samplefac; |
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40 |
greg |
2.1 |
extern int getgifpix(); |
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42 |
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COLR *scanln; |
43 |
greg |
2.2 |
BYTE *pixscan; |
44 |
greg |
2.1 |
|
45 |
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int xmax, ymax; /* picture size */ |
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47 |
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double gamv = 2.2; /* gamma correction */ |
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49 |
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int greyscale = 0; /* convert to B&W? */ |
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51 |
greg |
2.2 |
int dither = 1; /* dither colors? */ |
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53 |
greg |
2.1 |
int bradj = 0; /* brightness adjustment */ |
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char *progname; |
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main(argc, argv) |
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int argc; |
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char *argv[]; |
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{ |
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int ncolors = 0; |
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int bitsperpix; |
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int i; |
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#ifdef MSDOS |
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extern int _fmode; |
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_fmode = O_BINARY; |
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setmode(fileno(stdin), O_BINARY); |
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setmode(fileno(stdout), O_BINARY); |
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#endif |
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progname = argv[0]; |
72 |
greg |
2.4 |
samplefac = 0; |
73 |
greg |
2.1 |
|
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for (i = 1; i < argc; i++) |
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if (argv[i][0] == '-') |
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switch (argv[i][1]) { |
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case 'g': |
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gamv = atof(argv[++i]); |
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break; |
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case 'b': |
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greyscale = 1; |
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break; |
83 |
greg |
2.2 |
case 'd': |
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dither = !dither; |
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break; |
86 |
greg |
2.1 |
case 'c': |
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ncolors = atoi(argv[++i]); |
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break; |
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case 'e': |
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if (argv[i+1][0] != '+' && argv[i+1][0] != '-') |
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goto userr; |
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bradj = atoi(argv[++i]); |
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break; |
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greg |
2.4 |
case 'n': |
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samplefac = atoi(argv[++i]); |
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break; |
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greg |
2.1 |
default: |
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goto userr; |
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} |
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else |
101 |
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break; |
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103 |
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if (i < argc-2) |
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goto userr; |
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if (i <= argc-1 && freopen(argv[i], "r", stdin) == NULL) { |
106 |
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fprintf(stderr, "%s: cannot open input \"%s\"\n", |
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progname, argv[i]); |
108 |
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exit(1); |
109 |
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} |
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if (i == argc-2 && freopen(argv[i+1], "w", stdout) == NULL) { |
111 |
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fprintf(stderr, "%s: cannot open output \"%s\"\n", |
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progname, argv[i+1]); |
113 |
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exit(1); |
114 |
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} |
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if (checkheader(stdin, COLRFMT, NULL) < 0 || |
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fgetresolu(&xmax, &ymax, stdin) < 0) { |
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fprintf(stderr, "%s: bad picture format\n", progname); |
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exit(1); |
119 |
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} |
120 |
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picstart = ftell(stdin); |
121 |
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currow = -1; |
122 |
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scanln = (COLR *)malloc(xmax*sizeof(COLR)); |
123 |
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if (scanln == NULL) { |
124 |
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fprintf(stderr, "%s: out of memory\n", progname); |
125 |
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exit(1); |
126 |
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} |
127 |
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/* set up gamma correction */ |
128 |
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setcolrgam(gamv); |
129 |
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/* figure out the bits per pixel */ |
130 |
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if (ncolors < 2 | ncolors > MAXCOLORS) |
131 |
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ncolors = MAXCOLORS; |
132 |
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for (bitsperpix = 1; ncolors > 1<<bitsperpix; bitsperpix++) |
133 |
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; |
134 |
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/* compute color map */ |
135 |
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if (greyscale) |
136 |
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mkgrymap(ncolors); |
137 |
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else |
138 |
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mkclrmap(ncolors); |
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/* convert image */ |
140 |
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GIFEncode(stdout, xmax, ymax, 0, 0, bitsperpix, |
141 |
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rmap, gmap, bmap, getgifpix); |
142 |
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exit(0); |
143 |
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userr: |
144 |
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fprintf(stderr, |
145 |
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"Usage: %s [-b][-c ncolors][-g gamv][-e +/-stops] input [output]\n", |
146 |
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progname); |
147 |
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exit(1); |
148 |
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} |
149 |
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150 |
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151 |
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getrow(y) /* get the specified row from our image */ |
152 |
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int y; |
153 |
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{ |
154 |
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if (y == currow) |
155 |
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return; |
156 |
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if (y < currow) { |
157 |
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fseek(stdin, picstart, 0); |
158 |
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currow = -1; |
159 |
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} |
160 |
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do |
161 |
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if (freadcolrs(scanln, xmax, stdin) < 0) { |
162 |
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fprintf(stderr, "%s: error reading picture (y==%d)\n", |
163 |
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progname, ymax-1-y); |
164 |
greg |
2.3 |
exit(1); |
165 |
greg |
2.1 |
} |
166 |
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while (++currow < y); |
167 |
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if (bradj) |
168 |
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shiftcolrs(scanln, xmax, bradj); |
169 |
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colrs_gambs(scanln, xmax); |
170 |
greg |
2.2 |
if (pixscan != NULL) |
171 |
greg |
2.4 |
if (samplefac) |
172 |
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neu_dith_colrs(pixscan, scanln, xmax); |
173 |
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else |
174 |
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dith_colrs(pixscan, scanln, xmax); |
175 |
greg |
2.1 |
} |
176 |
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177 |
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178 |
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mkclrmap(nc) /* make our color map */ |
179 |
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int nc; |
180 |
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{ |
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register int i; |
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183 |
greg |
2.4 |
if ((samplefac ? neu_init(xmax*ymax) : new_histo(xmax*ymax)) == -1) |
184 |
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goto memerr; |
185 |
greg |
2.1 |
for (i = 0; i < ymax; i++) { |
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getrow(i); |
187 |
greg |
2.4 |
if (samplefac) |
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neu_colrs(scanln, xmax); |
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else |
190 |
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cnt_colrs(scanln, xmax); |
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greg |
2.1 |
} |
192 |
greg |
2.4 |
if (samplefac) |
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neu_clrtab(nc); |
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else |
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new_clrtab(nc); |
196 |
greg |
2.1 |
for (i = 0; i < nc; i++) { |
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rmap[i] = clrtab[i][RED]; |
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gmap[i] = clrtab[i][GRN]; |
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bmap[i] = clrtab[i][BLU]; |
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} |
201 |
greg |
2.4 |
if (dither && (pixscan = (BYTE *)malloc(xmax)) == NULL) |
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goto memerr; |
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return; |
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memerr: |
205 |
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fprintf(stderr, "%s: out of memory\n", progname); |
206 |
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exit(1); |
207 |
greg |
2.1 |
} |
208 |
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209 |
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210 |
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mkgrymap(nc) |
211 |
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int nc; |
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{ |
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register int i; |
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215 |
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for (i = 0; i < nc; i++) { |
216 |
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rmap[i] = |
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gmap[i] = |
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bmap[i] = ((unsigned)i<<8)/nc; |
219 |
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} |
220 |
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} |
221 |
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222 |
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223 |
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int |
224 |
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getgifpix(x, y) /* get a single pixel from our picture */ |
225 |
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int x, y; |
226 |
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{ |
227 |
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int pix; |
228 |
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229 |
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getrow(y); |
230 |
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if (greyscale) |
231 |
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return(normbright(scanln[x])); |
232 |
greg |
2.2 |
if (pixscan != NULL) |
233 |
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return(pixscan[x]); |
234 |
greg |
2.4 |
return(samplefac ? neu_map_pixel(scanln[x]) : map_pixel(scanln[x])); |
235 |
greg |
2.1 |
} |
236 |
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237 |
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238 |
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/* |
239 |
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* SCARY GIF code follows . . . . sorry. |
240 |
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* |
241 |
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* Based on GIFENCOD by David Rowley <[email protected]>.A |
242 |
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* Lempel-Zim compression based on "compress". |
243 |
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* |
244 |
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*/ |
245 |
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246 |
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/***************************************************************************** |
247 |
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* |
248 |
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* GIFENCODE.C - GIF Image compression interface |
249 |
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* |
250 |
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* GIFEncode( FName, GHeight, GWidth, GInterlace, Background, |
251 |
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* BitsPerPixel, Red, Green, Blue, GetPixel ) |
252 |
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* |
253 |
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*****************************************************************************/ |
254 |
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typedef int (* ifunptr)(); |
255 |
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256 |
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#define TRUE 1 |
257 |
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#define FALSE 0 |
258 |
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259 |
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int Width, Height; |
260 |
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int curx, cury; |
261 |
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long CountDown; |
262 |
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int Pass; |
263 |
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int Interlace; |
264 |
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unsigned long cur_accum = 0; |
265 |
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int cur_bits = 0; |
266 |
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267 |
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/* |
268 |
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* Bump the 'curx' and 'cury' to point to the next pixel |
269 |
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*/ |
270 |
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BumpPixel() |
271 |
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{ |
272 |
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curx++; |
273 |
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if( curx == Width ) { |
274 |
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curx = 0; |
275 |
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if( !Interlace ) { |
276 |
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cury++; |
277 |
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} else { |
278 |
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switch( Pass ) { |
279 |
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case 0: |
280 |
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cury += 8; |
281 |
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if( cury >= Height ) { |
282 |
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Pass++; |
283 |
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cury = 4; |
284 |
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} |
285 |
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break; |
286 |
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case 1: |
287 |
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cury += 8; |
288 |
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if( cury >= Height ) { |
289 |
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Pass++; |
290 |
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cury = 2; |
291 |
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} |
292 |
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break; |
293 |
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case 2: |
294 |
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cury += 4; |
295 |
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if( cury >= Height ) { |
296 |
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Pass++; |
297 |
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cury = 1; |
298 |
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} |
299 |
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break; |
300 |
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case 3: |
301 |
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cury += 2; |
302 |
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break; |
303 |
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} |
304 |
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} |
305 |
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} |
306 |
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} |
307 |
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308 |
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/* |
309 |
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* Return the next pixel from the image |
310 |
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*/ |
311 |
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GIFNextPixel( getpixel ) |
312 |
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ifunptr getpixel; |
313 |
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{ |
314 |
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int r; |
315 |
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316 |
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if( CountDown == 0 ) |
317 |
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return EOF; |
318 |
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CountDown--; |
319 |
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r = (*getpixel)( curx, cury ); |
320 |
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BumpPixel(); |
321 |
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return r; |
322 |
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} |
323 |
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324 |
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/* |
325 |
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* public GIFEncode |
326 |
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*/ |
327 |
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GIFEncode( fp, GWidth, GHeight, GInterlace, Background, |
328 |
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BitsPerPixel, Red, Green, Blue, GetPixel ) |
329 |
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FILE *fp; |
330 |
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int GWidth, GHeight; |
331 |
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int GInterlace; |
332 |
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int Background; |
333 |
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int BitsPerPixel; |
334 |
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int Red[], Green[], Blue[]; |
335 |
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ifunptr GetPixel; |
336 |
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{ |
337 |
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int B; |
338 |
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int RWidth, RHeight; |
339 |
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int LeftOfs, TopOfs; |
340 |
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int Resolution; |
341 |
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int ColorMapSize; |
342 |
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int InitCodeSize; |
343 |
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int i; |
344 |
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345 |
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long cur_accum = 0; |
346 |
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cur_bits = 0; |
347 |
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348 |
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Interlace = GInterlace; |
349 |
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ColorMapSize = 1 << BitsPerPixel; |
350 |
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RWidth = Width = GWidth; |
351 |
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RHeight = Height = GHeight; |
352 |
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LeftOfs = TopOfs = 0; |
353 |
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Resolution = BitsPerPixel; |
354 |
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355 |
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CountDown = (long)Width * (long)Height; |
356 |
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Pass = 0; |
357 |
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if( BitsPerPixel <= 1 ) |
358 |
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InitCodeSize = 2; |
359 |
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else |
360 |
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InitCodeSize = BitsPerPixel; |
361 |
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curx = cury = 0; |
362 |
|
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fwrite( "GIF87a", 1, 6, fp ); |
363 |
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Putword( RWidth, fp ); |
364 |
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Putword( RHeight, fp ); |
365 |
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B = 0x80; /* Yes, there is a color map */ |
366 |
|
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B |= (Resolution - 1) << 5; |
367 |
|
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B |= (BitsPerPixel - 1); |
368 |
|
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fputc( B, fp ); |
369 |
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fputc( Background, fp ); |
370 |
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fputc( 0, fp ); |
371 |
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for( i=0; i<ColorMapSize; i++ ) { |
372 |
|
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fputc( Red[i], fp ); |
373 |
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fputc( Green[i], fp ); |
374 |
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fputc( Blue[i], fp ); |
375 |
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} |
376 |
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fputc( ',', fp ); |
377 |
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Putword( LeftOfs, fp ); |
378 |
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Putword( TopOfs, fp ); |
379 |
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Putword( Width, fp ); |
380 |
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Putword( Height, fp ); |
381 |
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if( Interlace ) |
382 |
|
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fputc( 0x40, fp ); |
383 |
|
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else |
384 |
|
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fputc( 0x00, fp ); |
385 |
|
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fputc( InitCodeSize, fp ); |
386 |
|
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compress( InitCodeSize+1, fp, GetPixel ); |
387 |
|
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fputc( 0, fp ); |
388 |
|
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fputc( ';', fp ); |
389 |
|
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fclose( fp ); |
390 |
|
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} |
391 |
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|
392 |
|
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/* |
393 |
|
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* Write out a word to the GIF file |
394 |
|
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*/ |
395 |
|
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Putword( w, fp ) |
396 |
|
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int w; |
397 |
|
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FILE *fp; |
398 |
|
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{ |
399 |
|
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fputc( w & 0xff, fp ); |
400 |
|
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fputc( (w/256) & 0xff, fp ); |
401 |
|
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} |
402 |
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|
403 |
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|
404 |
|
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/*************************************************************************** |
405 |
|
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* |
406 |
|
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* GIFCOMPR.C - GIF Image compression routines |
407 |
|
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* |
408 |
|
|
* Lempel-Ziv compression based on 'compress'. GIF modifications by |
409 |
|
|
* David Rowley ([email protected]) |
410 |
|
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* |
411 |
|
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***************************************************************************/ |
412 |
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413 |
|
|
#define CBITS 12 |
414 |
|
|
#define HSIZE 5003 /* 80% occupancy */ |
415 |
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|
416 |
|
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/* |
417 |
|
|
* a code_int must be able to hold 2**CBITS values of type int, and also -1 |
418 |
|
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*/ |
419 |
|
|
typedef int code_int; |
420 |
|
|
typedef long int count_int; |
421 |
|
|
typedef unsigned char char_type; |
422 |
|
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|
423 |
|
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/* |
424 |
|
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* |
425 |
|
|
* GIF Image compression - modified 'compress' |
426 |
|
|
* |
427 |
|
|
* Based on: compress.c - File compression ala IEEE Computer, June 1984. |
428 |
|
|
* |
429 |
|
|
* By Authors: Spencer W. Thomas (decvax!harpo!utah-cs!utah-gr!thomas) |
430 |
|
|
* Jim McKie (decvax!mcvax!jim) |
431 |
|
|
* Steve Davies (decvax!vax135!petsd!peora!srd) |
432 |
|
|
* Ken Turkowski (decvax!decwrl!turtlevax!ken) |
433 |
|
|
* James A. Woods (decvax!ihnp4!ames!jaw) |
434 |
|
|
* Joe Orost (decvax!vax135!petsd!joe) |
435 |
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|
* |
436 |
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|
*/ |
437 |
|
|
#include <ctype.h> |
438 |
|
|
|
439 |
|
|
#define ARGVAL() (*++(*argv) || (--argc && *++argv)) |
440 |
|
|
|
441 |
|
|
int n_bits; /* number of bits/code */ |
442 |
|
|
int maxbits = CBITS; /* user settable max # bits/code */ |
443 |
|
|
code_int maxcode; /* maximum code, given n_bits */ |
444 |
|
|
code_int maxmaxcode = (code_int)1 << CBITS; /* should NEVER generate this code */ |
445 |
|
|
# define MAXCODE(n_bits) (((code_int) 1 << (n_bits)) - 1) |
446 |
|
|
|
447 |
|
|
count_int htab [HSIZE]; |
448 |
|
|
unsigned short codetab [HSIZE]; |
449 |
|
|
#define HashTabOf(i) htab[i] |
450 |
|
|
#define CodeTabOf(i) codetab[i] |
451 |
|
|
|
452 |
|
|
code_int hsize = HSIZE; /* for dynamic table sizing */ |
453 |
|
|
|
454 |
|
|
/* |
455 |
|
|
* To save much memory, we overlay the table used by compress() with those |
456 |
|
|
* used by decompress(). The tab_prefix table is the same size and type |
457 |
|
|
* as the codetab. The tab_suffix table needs 2**CBITS characters. We |
458 |
|
|
* get this from the beginning of htab. The output stack uses the rest |
459 |
|
|
* of htab, and contains characters. There is plenty of room for any |
460 |
|
|
* possible stack (stack used to be 8000 characters). |
461 |
|
|
*/ |
462 |
|
|
#define tab_prefixof(i) CodeTabOf(i) |
463 |
|
|
#define tab_suffixof(i) ((char_type *)(htab))[i] |
464 |
|
|
#define de_stack ((char_type *)&tab_suffixof((code_int)1<<CBITS)) |
465 |
|
|
|
466 |
|
|
code_int free_ent = 0; /* first unused entry */ |
467 |
|
|
|
468 |
|
|
/* |
469 |
|
|
* block compression parameters -- after all codes are used up, |
470 |
|
|
* and compression rate changes, start over. |
471 |
|
|
*/ |
472 |
|
|
int clear_flg = 0; |
473 |
|
|
int offset; |
474 |
|
|
long int in_count = 1; /* length of input */ |
475 |
|
|
long int out_count = 0; /* # of codes output (for debugging) */ |
476 |
|
|
|
477 |
|
|
/* |
478 |
|
|
* compress stdin to stdout |
479 |
|
|
* |
480 |
|
|
* Algorithm: use open addressing double hashing (no chaining) on the |
481 |
|
|
* prefix code / next character combination. We do a variant of Knuth's |
482 |
|
|
* algorithm D (vol. 3, sec. 6.4) along with G. Knott's relatively-prime |
483 |
|
|
* secondary probe. Here, the modular division first probe is gives way |
484 |
|
|
* to a faster exclusive-or manipulation. Also do block compression with |
485 |
|
|
* an adaptive reset, whereby the code table is cleared when the compression |
486 |
|
|
* ratio decreases, but after the table fills. The variable-length output |
487 |
|
|
* codes are re-sized at this point, and a special CLEAR code is generated |
488 |
|
|
* for the decompressor. Late addition: construct the table according to |
489 |
|
|
* file size for noticeable speed improvement on small files. Please direct |
490 |
|
|
* questions about this implementation to ames!jaw. |
491 |
|
|
*/ |
492 |
|
|
|
493 |
|
|
int g_init_bits; |
494 |
|
|
FILE *g_outfile; |
495 |
|
|
int ClearCode; |
496 |
|
|
int EOFCode; |
497 |
|
|
|
498 |
|
|
compress( init_bits, outfile, ReadValue ) |
499 |
|
|
int init_bits; |
500 |
|
|
FILE *outfile; |
501 |
|
|
ifunptr ReadValue; |
502 |
|
|
{ |
503 |
|
|
register long fcode; |
504 |
|
|
register code_int i = 0; |
505 |
|
|
register int c; |
506 |
|
|
register code_int ent; |
507 |
|
|
register code_int disp; |
508 |
|
|
register code_int hsize_reg; |
509 |
|
|
register int hshift; |
510 |
|
|
|
511 |
|
|
/* |
512 |
|
|
* Set up the globals: g_init_bits - initial number of bits |
513 |
|
|
* g_outfile - pointer to output file |
514 |
|
|
*/ |
515 |
|
|
g_init_bits = init_bits; |
516 |
|
|
g_outfile = outfile; |
517 |
|
|
/* |
518 |
|
|
* Set up the necessary values |
519 |
|
|
*/ |
520 |
|
|
offset = 0; |
521 |
|
|
out_count = 0; |
522 |
|
|
clear_flg = 0; |
523 |
|
|
in_count = 1; |
524 |
|
|
maxcode = MAXCODE(n_bits = g_init_bits); |
525 |
|
|
ClearCode = (1 << (init_bits - 1)); |
526 |
|
|
EOFCode = ClearCode + 1; |
527 |
|
|
free_ent = ClearCode + 2; |
528 |
|
|
char_init(); |
529 |
|
|
ent = GIFNextPixel( ReadValue ); |
530 |
|
|
hshift = 0; |
531 |
|
|
for ( fcode = (long) hsize; fcode < 65536L; fcode *= 2L ) |
532 |
|
|
hshift++; |
533 |
|
|
hshift = 8 - hshift; /* set hash code range bound */ |
534 |
|
|
hsize_reg = hsize; |
535 |
|
|
cl_hash( (count_int) hsize_reg); /* clear hash table */ |
536 |
|
|
output( (code_int)ClearCode ); |
537 |
|
|
while ( (c = GIFNextPixel( ReadValue )) != EOF ) { |
538 |
|
|
in_count++; |
539 |
|
|
fcode = (long) (((long) c << maxbits) + ent); |
540 |
|
|
/* i = (((code_int)c << hshift) ~ ent); /* xor hashing */ |
541 |
|
|
i = (((code_int)c << hshift) ^ ent); /* xor hashing */ |
542 |
|
|
if ( HashTabOf (i) == fcode ) { |
543 |
|
|
ent = CodeTabOf (i); |
544 |
|
|
continue; |
545 |
|
|
} else if ( (long)HashTabOf (i) < 0 ) /* empty slot */ |
546 |
|
|
goto nomatch; |
547 |
|
|
disp = hsize_reg - i; /* secondary hash (after G. Knott) */ |
548 |
|
|
if ( i == 0 ) |
549 |
|
|
disp = 1; |
550 |
|
|
probe: |
551 |
|
|
if ( (i -= disp) < 0 ) |
552 |
|
|
i += hsize_reg; |
553 |
|
|
if ( HashTabOf (i) == fcode ) { |
554 |
|
|
ent = CodeTabOf (i); |
555 |
|
|
continue; |
556 |
|
|
} |
557 |
|
|
if ( (long)HashTabOf (i) > 0 ) |
558 |
|
|
goto probe; |
559 |
|
|
nomatch: |
560 |
|
|
output ( (code_int) ent ); |
561 |
|
|
out_count++; |
562 |
|
|
ent = c; |
563 |
|
|
if ( free_ent < maxmaxcode ) { |
564 |
|
|
CodeTabOf (i) = free_ent++; /* code -> hashtable */ |
565 |
|
|
HashTabOf (i) = fcode; |
566 |
|
|
} else |
567 |
|
|
cl_block(); |
568 |
|
|
} |
569 |
|
|
/* |
570 |
|
|
* Put out the final code. |
571 |
|
|
*/ |
572 |
|
|
output( (code_int)ent ); |
573 |
|
|
out_count++; |
574 |
|
|
output( (code_int) EOFCode ); |
575 |
|
|
return; |
576 |
|
|
} |
577 |
|
|
|
578 |
|
|
/***************************************************************** |
579 |
|
|
* TAG( output ) |
580 |
|
|
* |
581 |
|
|
* Output the given code. |
582 |
|
|
* Inputs: |
583 |
|
|
* code: A n_bits-bit integer. If == -1, then EOF. This assumes |
584 |
|
|
* that n_bits =< (long)wordsize - 1. |
585 |
|
|
* Outputs: |
586 |
|
|
* Outputs code to the file. |
587 |
|
|
* Assumptions: |
588 |
|
|
* Chars are 8 bits long. |
589 |
|
|
* Algorithm: |
590 |
|
|
* Maintain a CBITS character long buffer (so that 8 codes will |
591 |
|
|
* fit in it exactly). Use the VAX insv instruction to insert each |
592 |
|
|
* code in turn. When the buffer fills up empty it and start over. |
593 |
|
|
*/ |
594 |
|
|
|
595 |
|
|
unsigned long masks[] = { 0x0000, 0x0001, 0x0003, 0x0007, 0x000F, |
596 |
|
|
0x001F, 0x003F, 0x007F, 0x00FF, |
597 |
|
|
0x01FF, 0x03FF, 0x07FF, 0x0FFF, |
598 |
|
|
0x1FFF, 0x3FFF, 0x7FFF, 0xFFFF }; |
599 |
|
|
|
600 |
|
|
output( code ) |
601 |
|
|
code_int code; |
602 |
|
|
{ |
603 |
|
|
cur_accum &= masks[ cur_bits ]; |
604 |
|
|
if( cur_bits > 0 ) |
605 |
|
|
cur_accum |= ((long)code << cur_bits); |
606 |
|
|
else |
607 |
|
|
cur_accum = code; |
608 |
|
|
cur_bits += n_bits; |
609 |
|
|
while( cur_bits >= 8 ) { |
610 |
|
|
char_out( (unsigned int)(cur_accum & 0xff) ); |
611 |
|
|
cur_accum >>= 8; |
612 |
|
|
cur_bits -= 8; |
613 |
|
|
} |
614 |
|
|
|
615 |
|
|
/* |
616 |
|
|
* If the next entry is going to be too big for the code size, |
617 |
|
|
* then increase it, if possible. |
618 |
|
|
*/ |
619 |
|
|
if ( free_ent > maxcode || clear_flg ) { |
620 |
|
|
if( clear_flg ) { |
621 |
|
|
maxcode = MAXCODE (n_bits = g_init_bits); |
622 |
|
|
clear_flg = 0; |
623 |
|
|
} else { |
624 |
|
|
n_bits++; |
625 |
|
|
if ( n_bits == maxbits ) |
626 |
|
|
maxcode = maxmaxcode; |
627 |
|
|
else |
628 |
|
|
maxcode = MAXCODE(n_bits); |
629 |
|
|
} |
630 |
|
|
} |
631 |
|
|
if( code == EOFCode ) { |
632 |
|
|
/* |
633 |
|
|
* At EOF, write the rest of the buffer. |
634 |
|
|
*/ |
635 |
|
|
while( cur_bits > 0 ) { |
636 |
|
|
char_out( (unsigned int)(cur_accum & 0xff) ); |
637 |
|
|
cur_accum >>= 8; |
638 |
|
|
cur_bits -= 8; |
639 |
|
|
} |
640 |
|
|
flush_char(); |
641 |
|
|
fflush( g_outfile ); |
642 |
|
|
if( ferror( g_outfile ) ) |
643 |
|
|
writeerr(); |
644 |
|
|
} |
645 |
|
|
} |
646 |
|
|
|
647 |
|
|
/* |
648 |
|
|
* Clear out the hash table |
649 |
|
|
*/ |
650 |
|
|
cl_block () /* table clear for block compress */ |
651 |
|
|
{ |
652 |
|
|
cl_hash ( (count_int) hsize ); |
653 |
|
|
free_ent = ClearCode + 2; |
654 |
|
|
clear_flg = 1; |
655 |
|
|
output( (code_int)ClearCode ); |
656 |
|
|
} |
657 |
|
|
|
658 |
|
|
cl_hash(hsize) /* reset code table */ |
659 |
|
|
register count_int hsize; |
660 |
|
|
{ |
661 |
|
|
register count_int *htab_p = htab+hsize; |
662 |
|
|
register long i; |
663 |
|
|
register long m1 = -1; |
664 |
|
|
|
665 |
|
|
i = hsize - 16; |
666 |
|
|
do { /* might use Sys V memset(3) here */ |
667 |
|
|
*(htab_p-16) = m1; |
668 |
|
|
*(htab_p-15) = m1; |
669 |
|
|
*(htab_p-14) = m1; |
670 |
|
|
*(htab_p-13) = m1; |
671 |
|
|
*(htab_p-12) = m1; |
672 |
|
|
*(htab_p-11) = m1; |
673 |
|
|
*(htab_p-10) = m1; |
674 |
|
|
*(htab_p-9) = m1; |
675 |
|
|
*(htab_p-8) = m1; |
676 |
|
|
*(htab_p-7) = m1; |
677 |
|
|
*(htab_p-6) = m1; |
678 |
|
|
*(htab_p-5) = m1; |
679 |
|
|
*(htab_p-4) = m1; |
680 |
|
|
*(htab_p-3) = m1; |
681 |
|
|
*(htab_p-2) = m1; |
682 |
|
|
*(htab_p-1) = m1; |
683 |
|
|
htab_p -= 16; |
684 |
|
|
} while ((i -= 16) >= 0); |
685 |
|
|
for ( i += 16; i > 0; i-- ) |
686 |
|
|
*--htab_p = m1; |
687 |
|
|
} |
688 |
|
|
|
689 |
|
|
writeerr() |
690 |
|
|
{ |
691 |
|
|
printf( "error writing output file\n" ); |
692 |
|
|
exit(1); |
693 |
|
|
} |
694 |
|
|
|
695 |
|
|
/****************************************************************************** |
696 |
|
|
* |
697 |
|
|
* GIF Specific routines |
698 |
|
|
* |
699 |
|
|
******************************************************************************/ |
700 |
|
|
|
701 |
|
|
/* |
702 |
|
|
* Number of characters so far in this 'packet' |
703 |
|
|
*/ |
704 |
|
|
int a_count; |
705 |
|
|
|
706 |
|
|
/* |
707 |
|
|
* Set up the 'byte output' routine |
708 |
|
|
*/ |
709 |
|
|
char_init() |
710 |
|
|
{ |
711 |
|
|
a_count = 0; |
712 |
|
|
} |
713 |
|
|
|
714 |
|
|
/* |
715 |
|
|
* Define the storage for the packet accumulator |
716 |
|
|
*/ |
717 |
|
|
char accum[256]; |
718 |
|
|
|
719 |
|
|
/* |
720 |
|
|
* Add a character to the end of the current packet, and if it is 254 |
721 |
|
|
* characters, flush the packet to disk. |
722 |
|
|
*/ |
723 |
|
|
char_out( c ) |
724 |
|
|
int c; |
725 |
|
|
{ |
726 |
|
|
accum[ a_count++ ] = c; |
727 |
|
|
if( a_count >= 254 ) |
728 |
|
|
flush_char(); |
729 |
|
|
} |
730 |
|
|
|
731 |
|
|
/* |
732 |
|
|
* Flush the packet to disk, and reset the accumulator |
733 |
|
|
*/ |
734 |
|
|
flush_char() |
735 |
|
|
{ |
736 |
|
|
if( a_count > 0 ) { |
737 |
|
|
fputc( a_count, g_outfile ); |
738 |
|
|
fwrite( accum, 1, a_count, g_outfile ); |
739 |
|
|
a_count = 0; |
740 |
|
|
} |
741 |
|
|
} |
742 |
|
|
|
743 |
|
|
static float curgamma; |
744 |
|
|
static short gamtab[256]; |
745 |
|
|
|
746 |
|
|
gammawarp(sbuf,gam,n) |
747 |
|
|
short *sbuf; |
748 |
|
|
float gam; |
749 |
|
|
int n; |
750 |
|
|
{ |
751 |
|
|
int i; |
752 |
|
|
float f; |
753 |
|
|
|
754 |
|
|
if(gam!=curgamma) { |
755 |
|
|
for(i=0; i<256; i++) |
756 |
|
|
gamtab[i] = 255*pow(i/255.0,gam)+0.5; |
757 |
|
|
curgamma = gam; |
758 |
|
|
} |
759 |
|
|
while(n--) { |
760 |
|
|
*sbuf = gamtab[*sbuf]; |
761 |
|
|
sbuf++; |
762 |
|
|
} |
763 |
|
|
} |