/* $Id: gif2tiff.c,v 1.8 2004/09/02 14:36:33 dron Exp $ */
/*
* Copyright (c) 1990-1997 Sam Leffler
* Copyright (c) 1991-1997 Silicon Graphics, Inc.
*
* Permission to use, copy, modify, distribute, and sell this software and
* its documentation for any purpose is hereby granted without fee, provided
* that (i) the above copyright notices and this permission notice appear in
* all copies of the software and related documentation, and (ii) the names of
* Sam Leffler and Silicon Graphics may not be used in any advertising or
* publicity relating to the software without the specific, prior written
* permission of Sam Leffler and Silicon Graphics.
*
* THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND,
* EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
* WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
*
* IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR
* ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
* OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
* WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
* LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
* OF THIS SOFTWARE.
*/
/*
* convert a GIF file into a TIFF file.
* based on Paul Haeberli's fromgif program which in turn is
* based on a GIF file reader by Marcel J.E. Mol March 23 1989
*
* if input is 320 by 200 pixel aspect is probably 1.2
* if input is 640 350 pixel aspect is probably 1.37
*
*/
#include "tif_config.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif
#include "tiffio.h"
#define GIFGAMMA (1.5) /* smaller makes output img brighter */
#define IMAX 0xffff /* max intensity value */
#define EXTRAFUDGE 128 /* some people write BAD .gif files */
#define streq(a,b) (strcmp(a,b) == 0)
#define strneq(a,b,n) (strncmp(a,b,n) == 0)
unsigned short gamtab[256];
void
makegamtab(float gam)
{
int i;
for(i=0; i<256; i++)
gamtab[i] = (unsigned short) (IMAX*pow(i/255.0,gam)+0.5);
}
char* stuff[] = {
"usage: gif2tiff [options] input.gif output.tif",
"where options are:",
" -r # make each strip have no more than # rows",
"",
" -c lzw[:opts] compress output with Lempel-Ziv & Welch encoding",
" -c zip[:opts] compress output with deflate encoding",
" -c packbits compress output with packbits encoding",
" -c none use no compression algorithm on output",
"",
"LZW and deflate options:",
" # set predictor value",
"For example, -c lzw:2 to get LZW-encoded data with horizontal differencing",
NULL
};
static void
usage(void)
{
char buf[BUFSIZ];
int i;
setbuf(stderr, buf);
fprintf(stderr, "%s\n\n", TIFFGetVersion());
for (i = 0; stuff[i] != NULL; i++)
fprintf(stderr, "%s\n", stuff[i]);
exit(-1);
}
#define COLSIZE 256
unsigned char *stackp;
unsigned int prefix[4096];
unsigned char suffix[4096];
unsigned char stack[4096];
int datasize,codesize,codemask; /* Decoder working variables */
int clear,eoi; /* Special code values */
int avail, oldcode;
FILE *infile;
int global; /* Is there a global color map? */
int globalbits; /* Number of bits of global colors */
unsigned char globalmap[COLSIZE][3];/* RGB values for global color map */
unsigned char *raster; /* Decoded image data */
unsigned long width, height;
unsigned short red[COLSIZE];
unsigned short green[COLSIZE];
unsigned short blue[COLSIZE];
char *filename, *imagename;
static uint16 compression = COMPRESSION_PACKBITS;
static uint16 predictor = 0;
static uint32 rowsperstrip = (uint32) -1;
static int processCompressOptions(char*);
int convert(void);
int checksignature(void);
void readscreen(void);
int readgifimage(char*);
void readextension(void);
int readraster(void);
int process(int, unsigned char**);
void initcolors(unsigned char [COLSIZE][3], int);
void rasterize(int, char*);
int
main(int argc, char* argv[])
{
extern int optind;
extern char *optarg;
int c, status;
while ((c = getopt(argc, argv, "c:r:")) != -1)
switch (c) {
case 'c': /* compression scheme */
if (!processCompressOptions(optarg))
usage();
break;
case 'r': /* rows/strip */
rowsperstrip = atoi(optarg);
break;
case '?':
usage();
/*NOTREACHED*/
}
if (argc - optind != 2)
usage();
makegamtab(GIFGAMMA);
filename = argv[optind];
imagename = argv[optind+1];
if ((infile = fopen(imagename, "rb")) != NULL) {
int c;
fclose(infile);
printf("overwrite %s? ", imagename); fflush(stdout);
c = getc(stdin);
if (c != 'y' && c != 'Y')
return (1);
}
if ((infile = fopen(filename, "rb")) == NULL) {
perror(filename);
return (1);
}
status = convert();
fclose(infile);
return (status);
}
static int
processCompressOptions(char* opt)
{
if (streq(opt, "none"))
compression = COMPRESSION_NONE;
else if (streq(opt, "packbits"))
compression = COMPRESSION_PACKBITS;
else if (strneq(opt, "lzw", 3)) {
char* cp = strchr(opt, ':');
if (cp)
predictor = atoi(cp+1);
compression = COMPRESSION_LZW;
} else if (strneq(opt, "zip", 3)) {
char* cp = strchr(opt, ':');
if (cp)
predictor = atoi(cp+1);
compression = COMPRESSION_DEFLATE;
} else
return (0);
return (1);
}
int
convert(void)
{
int ch;
char* mode = "w";
if (!checksignature())
return (-1);
readscreen();
while ((ch = getc(infile)) != ';' && ch != EOF) {
switch (ch) {
case '\0': break; /* this kludge for non-standard files */
case ',': if (!readgifimage(mode))
return (-1);
mode = "a"; /* subsequent images append */
break;
case '!': readextension();
break;
default: fprintf(stderr, "illegal GIF block type\n");
return (-1);
}
}
return (0);
}
int
checksignature(void)
{
char buf[6];
fread(buf,1,6,infile);
if (strncmp(buf,"GIF",3)) {
fprintf(stderr, "file is not a GIF file\n");
return 0;
}
if (strncmp(&buf[3],"87a",3)) {
fprintf(stderr, "unknown GIF version number\n");
return 0;
}
return 1;
}
/*
* readscreen -
* Get information which is global to all the images stored
* in the file
*/
void
readscreen(void)
{
unsigned char buf[7];
fread(buf,1,7,infile);
global = buf[4] & 0x80;
if (global) {
globalbits = (buf[4] & 0x07) + 1;
fread(globalmap,3,1<<globalbits,infile);
}
}
int
readgifimage(char* mode)
{
unsigned char buf[9];
int local, interleaved;
unsigned char localmap[256][3];
int localbits;
int status;
if (fread(buf, 1, 9, infile) == 0) {
perror(filename);
return (0);
}
width = buf[4] + (buf[5] << 8);
height = buf[6] + (buf[7] << 8);
local = buf[8] & 0x80;
interleaved = buf[8] & 0x40;
if (local == 0 && global == 0) {
fprintf(stderr, "no colormap present for image\n");
return (0);
}
if ((raster = (unsigned char*) _TIFFmalloc(width*height+EXTRAFUDGE)) == NULL) {
fprintf(stderr, "not enough memory for image\n");
return (0);
}
if (local) {
localbits = (buf[8] & 0x7) + 1;
fprintf(stderr, " local colors: %d\n", 1<<localbits);
fread(localmap, 3, 1<<localbits, infile);
initcolors(localmap, 1<<localbits);
} else if (global) {
initcolors(globalmap, 1<<globalbits);
}
if ((status = readraster()))
rasterize(interleaved, mode);
_TIFFfree(raster);
return status;
}
/*
* readextension -
* Read a GIF extension block (and do nothing with it).
*
*/
void
readextension(void)
{
int count;
char buf[255];
(void) getc(infile);
while ((count = getc(infile)))
fread(buf, 1, count, infile);
}
/*
* readraster -
* Decode a raster image
*
*/
int
readraster(void)
{
unsigned char *fill = raster;
unsigned char buf[255];
register int bits=0;
register unsigned long datum=0;
register unsigned char *ch;
register int count, code;
int status = 1;
datasize = getc(infile);
clear = 1 << datasize;
eoi = clear + 1;
avail = clear + 2;
oldcode = -1;
codesize = datasize + 1;
codemask = (1 << codesize) - 1;
for (code = 0; code < clear; code++) {
prefix[code] = 0;
suffix[code] = code;
}
stackp = stack;
for (count = getc(infile); count > 0; count = getc(infile)) {
fread(buf,1,count,infile);
for (ch=buf; count-- > 0; ch++) {
datum += (unsigned long) *ch << bits;
bits += 8;
while (bits >= codesize) {
code = datum & codemask;
datum >>= codesize;
bits -= codesize;
if (code == eoi) { /* This kludge put in */
goto exitloop; /* because some GIF files*/
} /* aren't standard */
if (!process(code, &fill)) {
status = 0;
goto exitloop;
}
}
}
if (fill >= raster + width*height) {
fprintf(stderr, "raster full before eoi code\n");
break;
}
}
exitloop:
if (fill != raster + width*height) {
fprintf(stderr, "warning: wrong rastersize: %ld bytes\n",
(long) (fill-raster));
fprintf(stderr, " instead of %ld bytes\n",
(long) width*height);
}
return status;
}
/*
* process -
* Process a compression code. "clear" resets the code table.
* Otherwise make a new code table entry, and output the bytes
* associated with the code.
*/
int
process(register int code, unsigned char** fill)
{
int incode;
static unsigned char firstchar;
if (code == clear) {
codesize = datasize + 1;
codemask = (1 << codesize) - 1;
avail = clear + 2;
oldcode = -1;
return 1;
}
if (oldcode == -1) {
*(*fill)++ = suffix[code];
firstchar = oldcode = code;
return 1;
}
if (code > avail) {
fprintf(stderr, "code %d too large for %d\n", code, avail);
return 0;
}
incode = code;
if (code == avail) { /* the first code is always < avail */
*stackp++ = firstchar;
code = oldcode;
}
while (code > clear) {
*stackp++ = suffix[code];
code = prefix[code];
}
*stackp++ = firstchar = suffix[code];
prefix[avail] = oldcode;
suffix[avail] = firstchar;
avail++;
if (((avail & codemask) == 0) && (avail < 4096)) {
codesize++;
codemask += avail;
}
oldcode = incode;
do {
*(*fill)++ = *--stackp;
} while (stackp > stack);
return 1;
}
/*
* initcolors -
* Convert a color map (local or global) to arrays with R, G and B
* values.
*
*/
void
initcolors(unsigned char colormap[COLSIZE][3], int ncolors)
{
register int i;
for (i = 0; i < ncolors; i++) {
red[i] = gamtab[colormap[i][0]];
green[i] = gamtab[colormap[i][1]];
blue[i] = gamtab[colormap[i][2]];
}
}
void
rasterize(int interleaved, char* mode)
{
register unsigned long row;
unsigned char *newras;
unsigned char *ras;
TIFF *tif;
tstrip_t strip;
tsize_t stripsize;
if ((newras = (unsigned char*) _TIFFmalloc(width*height+EXTRAFUDGE)) == NULL) {
fprintf(stderr, "not enough memory for image\n");
return;
}
#define DRAWSEGMENT(offset, step) { \
for (row = offset; row < height; row += step) { \
_TIFFmemcpy(newras + row*width, ras, width);\
ras += width; \
} \
}
ras = raster;
if (interleaved) {
DRAWSEGMENT(0, 8);
DRAWSEGMENT(4, 8);
DRAWSEGMENT(2, 4);
DRAWSEGMENT(1, 2);
} else
DRAWSEGMENT(0, 1);
#undef DRAWSEGMENT
tif = TIFFOpen(imagename, mode);
if (!tif) {
TIFFError(imagename,"Can not open output image");
exit(-1);
}
TIFFSetField(tif, TIFFTAG_IMAGEWIDTH, (uint32) width);
TIFFSetField(tif, TIFFTAG_IMAGELENGTH, (uint32) height);
TIFFSetField(tif, TIFFTAG_PHOTOMETRIC, PHOTOMETRIC_PALETTE);
TIFFSetField(tif, TIFFTAG_PLANARCONFIG, PLANARCONFIG_CONTIG);
TIFFSetField(tif, TIFFTAG_SAMPLESPERPIXEL, 1);
TIFFSetField(tif, TIFFTAG_BITSPERSAMPLE, 8);
TIFFSetField(tif, TIFFTAG_ROWSPERSTRIP,
rowsperstrip = TIFFDefaultStripSize(tif, rowsperstrip));
TIFFSetField(tif, TIFFTAG_COMPRESSION, compression);
switch (compression) {
case COMPRESSION_LZW:
case COMPRESSION_DEFLATE:
if (predictor != 0)
TIFFSetField(tif, TIFFTAG_PREDICTOR, predictor);
break;
}
TIFFSetField(tif, TIFFTAG_COLORMAP, red, green, blue);
TIFFSetField(tif, TIFFTAG_ORIENTATION, ORIENTATION_TOPLEFT);
strip = 0;
stripsize = TIFFStripSize(tif);
for (row=0; row<height; row += rowsperstrip) {
if (TIFFWriteEncodedStrip(tif, strip, newras+row*width, stripsize) < 0)
break;
strip++;
}
TIFFClose(tif);
_TIFFfree(newras);
}
/* vim: set ts=8 sts=8 sw=8 noet: */
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