| 1 |
greg |
2.1 |
/* Copyright (c) 1994 Regents of the University of California */
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| 2 |
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| 3 |
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#ifndef lint
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| 4 |
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static char SCCSid[] = "$SunId$ LBL";
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| 5 |
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#endif
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| 7 |
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/*
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| 8 |
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* Convert from Radiance picture file to Compuserve GIF.
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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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#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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#define MAXCOLORS 256
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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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int currow;
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extern long ftell();
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long picstart;
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extern BYTE clrtab[][3];
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extern int getgifpix();
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COLR *scanln;
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int xmax, ymax; /* picture size */
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double gamv = 2.2; /* gamma correction */
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int greyscale = 0; /* convert to B&W? */
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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];
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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;
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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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default:
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goto userr;
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}
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else
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break;
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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) {
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fprintf(stderr, "%s: cannot open input \"%s\"\n",
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progname, argv[i]);
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exit(1);
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}
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if (i == argc-2 && freopen(argv[i+1], "w", stdout) == NULL) {
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fprintf(stderr, "%s: cannot open output \"%s\"\n",
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progname, argv[i+1]);
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exit(1);
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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);
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}
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picstart = ftell(stdin);
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currow = -1;
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scanln = (COLR *)malloc(xmax*sizeof(COLR));
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if (scanln == NULL) {
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fprintf(stderr, "%s: out of memory\n", progname);
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exit(1);
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}
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/* set up gamma correction */
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setcolrgam(gamv);
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/* figure out the bits per pixel */
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if (ncolors < 2 | ncolors > MAXCOLORS)
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ncolors = MAXCOLORS;
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for (bitsperpix = 1; ncolors > 1<<bitsperpix; bitsperpix++)
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;
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/* compute color map */
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if (greyscale)
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mkgrymap(ncolors);
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else
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mkclrmap(ncolors);
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/* convert image */
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GIFEncode(stdout, xmax, ymax, 0, 0, bitsperpix,
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rmap, gmap, bmap, getgifpix);
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exit(0);
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userr:
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fprintf(stderr,
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"Usage: %s [-b][-c ncolors][-g gamv][-e +/-stops] input [output]\n",
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progname);
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exit(1);
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}
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getrow(y) /* get the specified row from our image */
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int y;
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{
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if (y == currow)
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return;
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| 144 |
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if (y < currow) {
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fseek(stdin, picstart, 0);
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currow = -1;
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}
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do
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if (freadcolrs(scanln, xmax, stdin) < 0) {
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fprintf(stderr, "%s: error reading picture (y==%d)\n",
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progname, ymax-1-y);
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}
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while (++currow < y);
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if (bradj)
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shiftcolrs(scanln, xmax, bradj);
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colrs_gambs(scanln, xmax);
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}
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mkclrmap(nc) /* make our color map */
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int nc;
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{
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register int i;
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new_histo();
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for (i = 0; i < ymax; i++) {
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getrow(i);
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cnt_colrs(scanln, xmax);
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}
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new_clrtab(nc);
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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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}
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}
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mkgrymap(nc)
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int nc;
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{
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register int i;
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for (i = 0; i < nc; i++) {
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rmap[i] =
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gmap[i] =
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bmap[i] = ((unsigned)i<<8)/nc;
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}
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}
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int
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getgifpix(x, y) /* get a single pixel from our picture */
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int x, y;
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{
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int pix;
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getrow(y);
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if (greyscale)
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return(normbright(scanln[x]));
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return(map_pixel(scanln[x]));
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}
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/*
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* SCARY GIF code follows . . . . sorry.
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*
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* Based on GIFENCOD by David Rowley <[email protected]>.A
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* Lempel-Zim compression based on "compress".
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*
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*/
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/*****************************************************************************
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*
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| 215 |
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* GIFENCODE.C - GIF Image compression interface
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*
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| 217 |
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* GIFEncode( FName, GHeight, GWidth, GInterlace, Background,
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| 218 |
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* BitsPerPixel, Red, Green, Blue, GetPixel )
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| 219 |
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*
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| 220 |
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*****************************************************************************/
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typedef int (* ifunptr)();
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| 223 |
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#define TRUE 1
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| 224 |
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#define FALSE 0
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| 225 |
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| 226 |
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int Width, Height;
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| 227 |
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int curx, cury;
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| 228 |
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long CountDown;
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| 229 |
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int Pass;
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| 230 |
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int Interlace;
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| 231 |
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unsigned long cur_accum = 0;
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| 232 |
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int cur_bits = 0;
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| 233 |
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| 234 |
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/*
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| 235 |
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* Bump the 'curx' and 'cury' to point to the next pixel
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| 236 |
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*/
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| 237 |
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BumpPixel()
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| 238 |
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{
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| 239 |
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curx++;
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| 240 |
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if( curx == Width ) {
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| 241 |
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curx = 0;
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| 242 |
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if( !Interlace ) {
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| 243 |
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cury++;
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| 244 |
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} else {
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| 245 |
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switch( Pass ) {
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| 246 |
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case 0:
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| 247 |
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cury += 8;
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| 248 |
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if( cury >= Height ) {
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| 249 |
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Pass++;
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| 250 |
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cury = 4;
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| 251 |
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}
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| 252 |
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break;
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| 253 |
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case 1:
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| 254 |
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cury += 8;
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| 255 |
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if( cury >= Height ) {
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| 256 |
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Pass++;
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| 257 |
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cury = 2;
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| 258 |
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}
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| 259 |
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break;
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| 260 |
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case 2:
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| 261 |
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cury += 4;
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| 262 |
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if( cury >= Height ) {
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| 263 |
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Pass++;
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| 264 |
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cury = 1;
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| 265 |
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}
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| 266 |
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break;
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| 267 |
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case 3:
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| 268 |
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cury += 2;
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| 269 |
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break;
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| 270 |
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}
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| 271 |
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}
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| 272 |
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}
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| 273 |
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}
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| 274 |
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| 275 |
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/*
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| 276 |
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* Return the next pixel from the image
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| 277 |
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*/
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| 278 |
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GIFNextPixel( getpixel )
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| 279 |
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ifunptr getpixel;
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| 280 |
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{
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| 281 |
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int r;
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| 282 |
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| 283 |
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if( CountDown == 0 )
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| 284 |
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return EOF;
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| 285 |
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CountDown--;
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| 286 |
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r = (*getpixel)( curx, cury );
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| 287 |
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BumpPixel();
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| 288 |
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return r;
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| 289 |
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}
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| 290 |
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| 291 |
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/*
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| 292 |
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* public GIFEncode
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| 293 |
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*/
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| 294 |
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GIFEncode( fp, GWidth, GHeight, GInterlace, Background,
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| 295 |
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BitsPerPixel, Red, Green, Blue, GetPixel )
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| 296 |
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FILE *fp;
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| 297 |
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int GWidth, GHeight;
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| 298 |
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int GInterlace;
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| 299 |
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int Background;
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| 300 |
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int BitsPerPixel;
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| 301 |
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int Red[], Green[], Blue[];
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| 302 |
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ifunptr GetPixel;
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| 303 |
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{
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| 304 |
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int B;
|
| 305 |
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int RWidth, RHeight;
|
| 306 |
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int LeftOfs, TopOfs;
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| 307 |
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int Resolution;
|
| 308 |
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int ColorMapSize;
|
| 309 |
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int InitCodeSize;
|
| 310 |
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int i;
|
| 311 |
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|
| 312 |
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long cur_accum = 0;
|
| 313 |
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cur_bits = 0;
|
| 314 |
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|
| 315 |
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Interlace = GInterlace;
|
| 316 |
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ColorMapSize = 1 << BitsPerPixel;
|
| 317 |
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RWidth = Width = GWidth;
|
| 318 |
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RHeight = Height = GHeight;
|
| 319 |
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LeftOfs = TopOfs = 0;
|
| 320 |
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Resolution = BitsPerPixel;
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| 321 |
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|
| 322 |
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CountDown = (long)Width * (long)Height;
|
| 323 |
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Pass = 0;
|
| 324 |
|
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if( BitsPerPixel <= 1 )
|
| 325 |
|
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InitCodeSize = 2;
|
| 326 |
|
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else
|
| 327 |
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InitCodeSize = BitsPerPixel;
|
| 328 |
|
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curx = cury = 0;
|
| 329 |
|
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fwrite( "GIF87a", 1, 6, fp );
|
| 330 |
|
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Putword( RWidth, fp );
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| 331 |
|
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Putword( RHeight, fp );
|
| 332 |
|
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B = 0x80; /* Yes, there is a color map */
|
| 333 |
|
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B |= (Resolution - 1) << 5;
|
| 334 |
|
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B |= (BitsPerPixel - 1);
|
| 335 |
|
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fputc( B, fp );
|
| 336 |
|
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fputc( Background, fp );
|
| 337 |
|
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fputc( 0, fp );
|
| 338 |
|
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for( i=0; i<ColorMapSize; i++ ) {
|
| 339 |
|
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fputc( Red[i], fp );
|
| 340 |
|
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fputc( Green[i], fp );
|
| 341 |
|
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fputc( Blue[i], fp );
|
| 342 |
|
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}
|
| 343 |
|
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fputc( ',', fp );
|
| 344 |
|
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Putword( LeftOfs, fp );
|
| 345 |
|
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Putword( TopOfs, fp );
|
| 346 |
|
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Putword( Width, fp );
|
| 347 |
|
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Putword( Height, fp );
|
| 348 |
|
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if( Interlace )
|
| 349 |
|
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fputc( 0x40, fp );
|
| 350 |
|
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else
|
| 351 |
|
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fputc( 0x00, fp );
|
| 352 |
|
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fputc( InitCodeSize, fp );
|
| 353 |
|
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compress( InitCodeSize+1, fp, GetPixel );
|
| 354 |
|
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fputc( 0, fp );
|
| 355 |
|
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fputc( ';', fp );
|
| 356 |
|
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fclose( fp );
|
| 357 |
|
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}
|
| 358 |
|
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|
| 359 |
|
|
/*
|
| 360 |
|
|
* Write out a word to the GIF file
|
| 361 |
|
|
*/
|
| 362 |
|
|
Putword( w, fp )
|
| 363 |
|
|
int w;
|
| 364 |
|
|
FILE *fp;
|
| 365 |
|
|
{
|
| 366 |
|
|
fputc( w & 0xff, fp );
|
| 367 |
|
|
fputc( (w/256) & 0xff, fp );
|
| 368 |
|
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}
|
| 369 |
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|
| 370 |
|
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|
| 371 |
|
|
/***************************************************************************
|
| 372 |
|
|
*
|
| 373 |
|
|
* GIFCOMPR.C - GIF Image compression routines
|
| 374 |
|
|
*
|
| 375 |
|
|
* Lempel-Ziv compression based on 'compress'. GIF modifications by
|
| 376 |
|
|
* David Rowley ([email protected])
|
| 377 |
|
|
*
|
| 378 |
|
|
***************************************************************************/
|
| 379 |
|
|
|
| 380 |
|
|
#define CBITS 12
|
| 381 |
|
|
#define HSIZE 5003 /* 80% occupancy */
|
| 382 |
|
|
|
| 383 |
|
|
/*
|
| 384 |
|
|
* a code_int must be able to hold 2**CBITS values of type int, and also -1
|
| 385 |
|
|
*/
|
| 386 |
|
|
typedef int code_int;
|
| 387 |
|
|
typedef long int count_int;
|
| 388 |
|
|
typedef unsigned char char_type;
|
| 389 |
|
|
|
| 390 |
|
|
/*
|
| 391 |
|
|
*
|
| 392 |
|
|
* GIF Image compression - modified 'compress'
|
| 393 |
|
|
*
|
| 394 |
|
|
* Based on: compress.c - File compression ala IEEE Computer, June 1984.
|
| 395 |
|
|
*
|
| 396 |
|
|
* By Authors: Spencer W. Thomas (decvax!harpo!utah-cs!utah-gr!thomas)
|
| 397 |
|
|
* Jim McKie (decvax!mcvax!jim)
|
| 398 |
|
|
* Steve Davies (decvax!vax135!petsd!peora!srd)
|
| 399 |
|
|
* Ken Turkowski (decvax!decwrl!turtlevax!ken)
|
| 400 |
|
|
* James A. Woods (decvax!ihnp4!ames!jaw)
|
| 401 |
|
|
* Joe Orost (decvax!vax135!petsd!joe)
|
| 402 |
|
|
*
|
| 403 |
|
|
*/
|
| 404 |
|
|
#include <ctype.h>
|
| 405 |
|
|
|
| 406 |
|
|
#define ARGVAL() (*++(*argv) || (--argc && *++argv))
|
| 407 |
|
|
|
| 408 |
|
|
int n_bits; /* number of bits/code */
|
| 409 |
|
|
int maxbits = CBITS; /* user settable max # bits/code */
|
| 410 |
|
|
code_int maxcode; /* maximum code, given n_bits */
|
| 411 |
|
|
code_int maxmaxcode = (code_int)1 << CBITS; /* should NEVER generate this code */
|
| 412 |
|
|
# define MAXCODE(n_bits) (((code_int) 1 << (n_bits)) - 1)
|
| 413 |
|
|
|
| 414 |
|
|
count_int htab [HSIZE];
|
| 415 |
|
|
unsigned short codetab [HSIZE];
|
| 416 |
|
|
#define HashTabOf(i) htab[i]
|
| 417 |
|
|
#define CodeTabOf(i) codetab[i]
|
| 418 |
|
|
|
| 419 |
|
|
code_int hsize = HSIZE; /* for dynamic table sizing */
|
| 420 |
|
|
|
| 421 |
|
|
/*
|
| 422 |
|
|
* To save much memory, we overlay the table used by compress() with those
|
| 423 |
|
|
* used by decompress(). The tab_prefix table is the same size and type
|
| 424 |
|
|
* as the codetab. The tab_suffix table needs 2**CBITS characters. We
|
| 425 |
|
|
* get this from the beginning of htab. The output stack uses the rest
|
| 426 |
|
|
* of htab, and contains characters. There is plenty of room for any
|
| 427 |
|
|
* possible stack (stack used to be 8000 characters).
|
| 428 |
|
|
*/
|
| 429 |
|
|
#define tab_prefixof(i) CodeTabOf(i)
|
| 430 |
|
|
#define tab_suffixof(i) ((char_type *)(htab))[i]
|
| 431 |
|
|
#define de_stack ((char_type *)&tab_suffixof((code_int)1<<CBITS))
|
| 432 |
|
|
|
| 433 |
|
|
code_int free_ent = 0; /* first unused entry */
|
| 434 |
|
|
|
| 435 |
|
|
/*
|
| 436 |
|
|
* block compression parameters -- after all codes are used up,
|
| 437 |
|
|
* and compression rate changes, start over.
|
| 438 |
|
|
*/
|
| 439 |
|
|
int clear_flg = 0;
|
| 440 |
|
|
int offset;
|
| 441 |
|
|
long int in_count = 1; /* length of input */
|
| 442 |
|
|
long int out_count = 0; /* # of codes output (for debugging) */
|
| 443 |
|
|
|
| 444 |
|
|
/*
|
| 445 |
|
|
* compress stdin to stdout
|
| 446 |
|
|
*
|
| 447 |
|
|
* Algorithm: use open addressing double hashing (no chaining) on the
|
| 448 |
|
|
* prefix code / next character combination. We do a variant of Knuth's
|
| 449 |
|
|
* algorithm D (vol. 3, sec. 6.4) along with G. Knott's relatively-prime
|
| 450 |
|
|
* secondary probe. Here, the modular division first probe is gives way
|
| 451 |
|
|
* to a faster exclusive-or manipulation. Also do block compression with
|
| 452 |
|
|
* an adaptive reset, whereby the code table is cleared when the compression
|
| 453 |
|
|
* ratio decreases, but after the table fills. The variable-length output
|
| 454 |
|
|
* codes are re-sized at this point, and a special CLEAR code is generated
|
| 455 |
|
|
* for the decompressor. Late addition: construct the table according to
|
| 456 |
|
|
* file size for noticeable speed improvement on small files. Please direct
|
| 457 |
|
|
* questions about this implementation to ames!jaw.
|
| 458 |
|
|
*/
|
| 459 |
|
|
|
| 460 |
|
|
int g_init_bits;
|
| 461 |
|
|
FILE *g_outfile;
|
| 462 |
|
|
int ClearCode;
|
| 463 |
|
|
int EOFCode;
|
| 464 |
|
|
|
| 465 |
|
|
compress( init_bits, outfile, ReadValue )
|
| 466 |
|
|
int init_bits;
|
| 467 |
|
|
FILE *outfile;
|
| 468 |
|
|
ifunptr ReadValue;
|
| 469 |
|
|
{
|
| 470 |
|
|
register long fcode;
|
| 471 |
|
|
register code_int i = 0;
|
| 472 |
|
|
register int c;
|
| 473 |
|
|
register code_int ent;
|
| 474 |
|
|
register code_int disp;
|
| 475 |
|
|
register code_int hsize_reg;
|
| 476 |
|
|
register int hshift;
|
| 477 |
|
|
|
| 478 |
|
|
/*
|
| 479 |
|
|
* Set up the globals: g_init_bits - initial number of bits
|
| 480 |
|
|
* g_outfile - pointer to output file
|
| 481 |
|
|
*/
|
| 482 |
|
|
g_init_bits = init_bits;
|
| 483 |
|
|
g_outfile = outfile;
|
| 484 |
|
|
/*
|
| 485 |
|
|
* Set up the necessary values
|
| 486 |
|
|
*/
|
| 487 |
|
|
offset = 0;
|
| 488 |
|
|
out_count = 0;
|
| 489 |
|
|
clear_flg = 0;
|
| 490 |
|
|
in_count = 1;
|
| 491 |
|
|
maxcode = MAXCODE(n_bits = g_init_bits);
|
| 492 |
|
|
ClearCode = (1 << (init_bits - 1));
|
| 493 |
|
|
EOFCode = ClearCode + 1;
|
| 494 |
|
|
free_ent = ClearCode + 2;
|
| 495 |
|
|
char_init();
|
| 496 |
|
|
ent = GIFNextPixel( ReadValue );
|
| 497 |
|
|
hshift = 0;
|
| 498 |
|
|
for ( fcode = (long) hsize; fcode < 65536L; fcode *= 2L )
|
| 499 |
|
|
hshift++;
|
| 500 |
|
|
hshift = 8 - hshift; /* set hash code range bound */
|
| 501 |
|
|
hsize_reg = hsize;
|
| 502 |
|
|
cl_hash( (count_int) hsize_reg); /* clear hash table */
|
| 503 |
|
|
output( (code_int)ClearCode );
|
| 504 |
|
|
while ( (c = GIFNextPixel( ReadValue )) != EOF ) {
|
| 505 |
|
|
in_count++;
|
| 506 |
|
|
fcode = (long) (((long) c << maxbits) + ent);
|
| 507 |
|
|
/* i = (((code_int)c << hshift) ~ ent); /* xor hashing */
|
| 508 |
|
|
i = (((code_int)c << hshift) ^ ent); /* xor hashing */
|
| 509 |
|
|
if ( HashTabOf (i) == fcode ) {
|
| 510 |
|
|
ent = CodeTabOf (i);
|
| 511 |
|
|
continue;
|
| 512 |
|
|
} else if ( (long)HashTabOf (i) < 0 ) /* empty slot */
|
| 513 |
|
|
goto nomatch;
|
| 514 |
|
|
disp = hsize_reg - i; /* secondary hash (after G. Knott) */
|
| 515 |
|
|
if ( i == 0 )
|
| 516 |
|
|
disp = 1;
|
| 517 |
|
|
probe:
|
| 518 |
|
|
if ( (i -= disp) < 0 )
|
| 519 |
|
|
i += hsize_reg;
|
| 520 |
|
|
if ( HashTabOf (i) == fcode ) {
|
| 521 |
|
|
ent = CodeTabOf (i);
|
| 522 |
|
|
continue;
|
| 523 |
|
|
}
|
| 524 |
|
|
if ( (long)HashTabOf (i) > 0 )
|
| 525 |
|
|
goto probe;
|
| 526 |
|
|
nomatch:
|
| 527 |
|
|
output ( (code_int) ent );
|
| 528 |
|
|
out_count++;
|
| 529 |
|
|
ent = c;
|
| 530 |
|
|
if ( free_ent < maxmaxcode ) {
|
| 531 |
|
|
CodeTabOf (i) = free_ent++; /* code -> hashtable */
|
| 532 |
|
|
HashTabOf (i) = fcode;
|
| 533 |
|
|
} else
|
| 534 |
|
|
cl_block();
|
| 535 |
|
|
}
|
| 536 |
|
|
/*
|
| 537 |
|
|
* Put out the final code.
|
| 538 |
|
|
*/
|
| 539 |
|
|
output( (code_int)ent );
|
| 540 |
|
|
out_count++;
|
| 541 |
|
|
output( (code_int) EOFCode );
|
| 542 |
|
|
return;
|
| 543 |
|
|
}
|
| 544 |
|
|
|
| 545 |
|
|
/*****************************************************************
|
| 546 |
|
|
* TAG( output )
|
| 547 |
|
|
*
|
| 548 |
|
|
* Output the given code.
|
| 549 |
|
|
* Inputs:
|
| 550 |
|
|
* code: A n_bits-bit integer. If == -1, then EOF. This assumes
|
| 551 |
|
|
* that n_bits =< (long)wordsize - 1.
|
| 552 |
|
|
* Outputs:
|
| 553 |
|
|
* Outputs code to the file.
|
| 554 |
|
|
* Assumptions:
|
| 555 |
|
|
* Chars are 8 bits long.
|
| 556 |
|
|
* Algorithm:
|
| 557 |
|
|
* Maintain a CBITS character long buffer (so that 8 codes will
|
| 558 |
|
|
* fit in it exactly). Use the VAX insv instruction to insert each
|
| 559 |
|
|
* code in turn. When the buffer fills up empty it and start over.
|
| 560 |
|
|
*/
|
| 561 |
|
|
|
| 562 |
|
|
unsigned long masks[] = { 0x0000, 0x0001, 0x0003, 0x0007, 0x000F,
|
| 563 |
|
|
0x001F, 0x003F, 0x007F, 0x00FF,
|
| 564 |
|
|
0x01FF, 0x03FF, 0x07FF, 0x0FFF,
|
| 565 |
|
|
0x1FFF, 0x3FFF, 0x7FFF, 0xFFFF };
|
| 566 |
|
|
|
| 567 |
|
|
output( code )
|
| 568 |
|
|
code_int code;
|
| 569 |
|
|
{
|
| 570 |
|
|
cur_accum &= masks[ cur_bits ];
|
| 571 |
|
|
if( cur_bits > 0 )
|
| 572 |
|
|
cur_accum |= ((long)code << cur_bits);
|
| 573 |
|
|
else
|
| 574 |
|
|
cur_accum = code;
|
| 575 |
|
|
cur_bits += n_bits;
|
| 576 |
|
|
while( cur_bits >= 8 ) {
|
| 577 |
|
|
char_out( (unsigned int)(cur_accum & 0xff) );
|
| 578 |
|
|
cur_accum >>= 8;
|
| 579 |
|
|
cur_bits -= 8;
|
| 580 |
|
|
}
|
| 581 |
|
|
|
| 582 |
|
|
/*
|
| 583 |
|
|
* If the next entry is going to be too big for the code size,
|
| 584 |
|
|
* then increase it, if possible.
|
| 585 |
|
|
*/
|
| 586 |
|
|
if ( free_ent > maxcode || clear_flg ) {
|
| 587 |
|
|
if( clear_flg ) {
|
| 588 |
|
|
maxcode = MAXCODE (n_bits = g_init_bits);
|
| 589 |
|
|
clear_flg = 0;
|
| 590 |
|
|
} else {
|
| 591 |
|
|
n_bits++;
|
| 592 |
|
|
if ( n_bits == maxbits )
|
| 593 |
|
|
maxcode = maxmaxcode;
|
| 594 |
|
|
else
|
| 595 |
|
|
maxcode = MAXCODE(n_bits);
|
| 596 |
|
|
}
|
| 597 |
|
|
}
|
| 598 |
|
|
if( code == EOFCode ) {
|
| 599 |
|
|
/*
|
| 600 |
|
|
* At EOF, write the rest of the buffer.
|
| 601 |
|
|
*/
|
| 602 |
|
|
while( cur_bits > 0 ) {
|
| 603 |
|
|
char_out( (unsigned int)(cur_accum & 0xff) );
|
| 604 |
|
|
cur_accum >>= 8;
|
| 605 |
|
|
cur_bits -= 8;
|
| 606 |
|
|
}
|
| 607 |
|
|
flush_char();
|
| 608 |
|
|
fflush( g_outfile );
|
| 609 |
|
|
if( ferror( g_outfile ) )
|
| 610 |
|
|
writeerr();
|
| 611 |
|
|
}
|
| 612 |
|
|
}
|
| 613 |
|
|
|
| 614 |
|
|
/*
|
| 615 |
|
|
* Clear out the hash table
|
| 616 |
|
|
*/
|
| 617 |
|
|
cl_block () /* table clear for block compress */
|
| 618 |
|
|
{
|
| 619 |
|
|
cl_hash ( (count_int) hsize );
|
| 620 |
|
|
free_ent = ClearCode + 2;
|
| 621 |
|
|
clear_flg = 1;
|
| 622 |
|
|
output( (code_int)ClearCode );
|
| 623 |
|
|
}
|
| 624 |
|
|
|
| 625 |
|
|
cl_hash(hsize) /* reset code table */
|
| 626 |
|
|
register count_int hsize;
|
| 627 |
|
|
{
|
| 628 |
|
|
register count_int *htab_p = htab+hsize;
|
| 629 |
|
|
register long i;
|
| 630 |
|
|
register long m1 = -1;
|
| 631 |
|
|
|
| 632 |
|
|
i = hsize - 16;
|
| 633 |
|
|
do { /* might use Sys V memset(3) here */
|
| 634 |
|
|
*(htab_p-16) = m1;
|
| 635 |
|
|
*(htab_p-15) = m1;
|
| 636 |
|
|
*(htab_p-14) = m1;
|
| 637 |
|
|
*(htab_p-13) = m1;
|
| 638 |
|
|
*(htab_p-12) = m1;
|
| 639 |
|
|
*(htab_p-11) = m1;
|
| 640 |
|
|
*(htab_p-10) = m1;
|
| 641 |
|
|
*(htab_p-9) = m1;
|
| 642 |
|
|
*(htab_p-8) = m1;
|
| 643 |
|
|
*(htab_p-7) = m1;
|
| 644 |
|
|
*(htab_p-6) = m1;
|
| 645 |
|
|
*(htab_p-5) = m1;
|
| 646 |
|
|
*(htab_p-4) = m1;
|
| 647 |
|
|
*(htab_p-3) = m1;
|
| 648 |
|
|
*(htab_p-2) = m1;
|
| 649 |
|
|
*(htab_p-1) = m1;
|
| 650 |
|
|
htab_p -= 16;
|
| 651 |
|
|
} while ((i -= 16) >= 0);
|
| 652 |
|
|
for ( i += 16; i > 0; i-- )
|
| 653 |
|
|
*--htab_p = m1;
|
| 654 |
|
|
}
|
| 655 |
|
|
|
| 656 |
|
|
writeerr()
|
| 657 |
|
|
{
|
| 658 |
|
|
printf( "error writing output file\n" );
|
| 659 |
|
|
exit(1);
|
| 660 |
|
|
}
|
| 661 |
|
|
|
| 662 |
|
|
/******************************************************************************
|
| 663 |
|
|
*
|
| 664 |
|
|
* GIF Specific routines
|
| 665 |
|
|
*
|
| 666 |
|
|
******************************************************************************/
|
| 667 |
|
|
|
| 668 |
|
|
/*
|
| 669 |
|
|
* Number of characters so far in this 'packet'
|
| 670 |
|
|
*/
|
| 671 |
|
|
int a_count;
|
| 672 |
|
|
|
| 673 |
|
|
/*
|
| 674 |
|
|
* Set up the 'byte output' routine
|
| 675 |
|
|
*/
|
| 676 |
|
|
char_init()
|
| 677 |
|
|
{
|
| 678 |
|
|
a_count = 0;
|
| 679 |
|
|
}
|
| 680 |
|
|
|
| 681 |
|
|
/*
|
| 682 |
|
|
* Define the storage for the packet accumulator
|
| 683 |
|
|
*/
|
| 684 |
|
|
char accum[256];
|
| 685 |
|
|
|
| 686 |
|
|
/*
|
| 687 |
|
|
* Add a character to the end of the current packet, and if it is 254
|
| 688 |
|
|
* characters, flush the packet to disk.
|
| 689 |
|
|
*/
|
| 690 |
|
|
char_out( c )
|
| 691 |
|
|
int c;
|
| 692 |
|
|
{
|
| 693 |
|
|
accum[ a_count++ ] = c;
|
| 694 |
|
|
if( a_count >= 254 )
|
| 695 |
|
|
flush_char();
|
| 696 |
|
|
}
|
| 697 |
|
|
|
| 698 |
|
|
/*
|
| 699 |
|
|
* Flush the packet to disk, and reset the accumulator
|
| 700 |
|
|
*/
|
| 701 |
|
|
flush_char()
|
| 702 |
|
|
{
|
| 703 |
|
|
if( a_count > 0 ) {
|
| 704 |
|
|
fputc( a_count, g_outfile );
|
| 705 |
|
|
fwrite( accum, 1, a_count, g_outfile );
|
| 706 |
|
|
a_count = 0;
|
| 707 |
|
|
}
|
| 708 |
|
|
}
|
| 709 |
|
|
|
| 710 |
|
|
static float curgamma;
|
| 711 |
|
|
static short gamtab[256];
|
| 712 |
|
|
|
| 713 |
|
|
gammawarp(sbuf,gam,n)
|
| 714 |
|
|
short *sbuf;
|
| 715 |
|
|
float gam;
|
| 716 |
|
|
int n;
|
| 717 |
|
|
{
|
| 718 |
|
|
int i;
|
| 719 |
|
|
float f;
|
| 720 |
|
|
|
| 721 |
|
|
if(gam!=curgamma) {
|
| 722 |
|
|
for(i=0; i<256; i++)
|
| 723 |
|
|
gamtab[i] = 255*pow(i/255.0,gam)+0.5;
|
| 724 |
|
|
curgamma = gam;
|
| 725 |
|
|
}
|
| 726 |
|
|
while(n--) {
|
| 727 |
|
|
*sbuf = gamtab[*sbuf];
|
| 728 |
|
|
sbuf++;
|
| 729 |
|
|
}
|
| 730 |
|
|
}
|
