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/*
* gif2png.c
* Copyright (C) 1995 Alexander Lehmann
* Copyright (C) 1999 by Eric S. Raymond.
* For conditions of distribution and use, see the file COPYING.
*/
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h> /* for isatty() */
#include <zlib.h>
#include <sys/stat.h>
#include <utime.h>
#include <stdbool.h>
#include "gif2png.h"
/* Define png_jmpbuf() in case we are using a pre-1.0.6 version of libpng */
#ifndef png_jmpbuf
# define png_jmpbuf(png_ptr) (png_ptr->jmpbuf)
#endif
/*@i1@*/struct GIFelement first={NULL};
struct GIFelement *current;
bool recover = false;
int verbose = 0;
static bool delete = false;
static bool optimize = false;
static bool histogram = false;
static int interlaced = PNG_INTERLACE_LAST;
static bool preserve_mtime = false;
static bool progress = false;
static bool webconvert = false;
static bool software_chunk = true;
static bool filtermode = false;
static bool matte = false;
static bool gamma_srgb = false;
static GifColor matte_color;
static long numgifs = 0L;
static long numpngs = 0L;
int interlace_line(int height, int line)
/* return the actual line # used to store an interlaced line */
{
int res;
/*@-shiftimplementation@*/
if ((line & 7) == 0) {
return line >> 3;
}
res = (height+7) >> 3;
if ((line & 7) == 4) {
return res+((line-4) >> 3);
}
res += (height+3) >> 3;
if ((line & 3) == 2) {
return res + ((line-2) >> 2);
}
return res + ((height+1) >> 2) + ((line-1) >> 1);
/*@=shiftimplementation@*/
}
int inv_interlace_line(int height, int line)
/* inverse function of above, used for recovery of interlaced images */
{
/*@-shiftimplementation@*/
if ((line << 3)<height) {
return line << 3;
}
line -= (height+7) >> 3;
if ((line << 3) + 4 < height) {
return (line << 3) + 4;
}
line -= (height+3) >> 3;
if ((line << 2) + 2 < height) {
return (line << 2) + 2;
}
line -= (height + 1) >> 2;
return (line << 1) + 1;
/*@=shiftimplementation@*/
}
/*
* Do some adjustments of the color palette.
*
* We won't check for duplicate colors, this is probably only a very
* rare case, but we check if all used colors are grays. Some GIF
* writers (e.g. some versions of ppmtogif) leave the unused entries
* uninitialized, which breaks the detection of grayscale images
* (e.g. in QPV).
*
* If the image is grayscale we will use PNG color type 0, except when
* the transparency color is also appearing as a visible color. In
* this case we write a paletted image. Another solution would be
* gray+alpha, but that would probably increase the image size too
* much.
*
* If there are only few gray levels (<=16), we try to create a 4-bit
* or less grayscale file, but if the gray levels do not fit into the
* necessary grid, we write a paletted image--e.g., if the image
* contains black, white and 50% gray, the grayscale image would
* require 8-bit, but the paletted image only 2-bit. Even with
* filtering, the 8-bit file will be larger.
*/
static bool is_gray(png_color c)
{
/* check if r==g==b, moved to function to work around NeXTstep 3.3 cc bug.
* life could be so easy if at least the basic tools worked as expected.
*/
return c.red == c.green && c.green == c.blue;
}
/*@-globstate -mustfreefresh @*/
static int writefile(struct GIFelement *s, struct GIFelement *e,
FILE *fp, bool lastimg)
{
int i;
struct GIFimagestruct *img = e->imagestruct;
unsigned long *count = img->color_count;
GifColor *colors = img->colors;
int colors_used = 0;
byte remap[MAXCMSIZE];
bool low_prec;
png_struct *png_ptr;
png_info *info_ptr;
int p;
int gray_bitdepth;
png_color pal_rgb[MAXCMSIZE], *pltep;
png_byte pal_trans[MAXCMSIZE];
png_color_16 color16trans, color16back;
byte buffer[24]; /* used for gIFt and gIFg */
int j;
png_uint_16 histogr[MAXCMSIZE];
unsigned long hist_maxvalue;
int passcount;
int errtype, errorcount = 0;
png_text software;
png_text comment;
/* these volatile declarations prevent gcc warnings ("variable might be
* clobbered by `longjmp' or `vfork'") */
volatile bool gray = true;
volatile int last_color = 0;
volatile bool remapping = false;
volatile int bitdepth;
/*@-nullpass@*/
png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
if (png_ptr == NULL) {
(void)fprintf(stderr, "gif2png: fatal error, out of memory\n");
(void)fprintf(stderr, "gif2png: exiting ungracefully\n");
exit(1);
}
info_ptr = png_create_info_struct(png_ptr);
if (info_ptr == NULL) {
(void)fprintf(stderr, "gif2png: fatal error, out of memory\n");
(void)fprintf(stderr, "gif2png: exiting ungracefully\n");
exit(1);
}
/*@=nullpass@*/
/* pacify splint by defining all this storage */
memset(remap, '\0', sizeof(remap));
memset(pal_rgb, '\0', sizeof(pal_rgb));
memset(pal_trans, '\0', sizeof(pal_trans));
/* ignore the transparency value if no pixel in the image uses it */
if (img->trans != -1 && count[img->trans] == 0)
img->trans = -1;
if (optimize) {
/* zero out unused color table entries and use zlib level 9 */
for (i = 0; i < MAXCMSIZE; i++)
if(count[i] == 0)
colors[i].red = colors[i].green = colors[i].blue = 0;
/*
* The way that last_color is computed ensures that trailing zeroed-out
* entries will be dropped.
* FIXME: someday, actually compact unused colors out of the table
* and remap pixels appropriately.
*/
} else if (!recover) {
/* report unused colors so user can choose to reconvert */
int unused = 0;
for (i = 0; i < MAXCMSIZE; i++)
if (count[i] == 0)
unused++;
if (unused > 0)
{
(void)fprintf(stderr,
"gif2png: %d unused colors; convert with -O to remove\n",
unused);
errorcount++;
}
}
for (i = 0; i < MAXCMSIZE; i++)
if (count[i] != 0) {
gray &= is_gray(colors[i]);
colors_used++;
if (last_color < i)
last_color = i;
}
if (gray) {
if (verbose > 1)
(void)fprintf(stderr, "gif2png: input image is grayscale\n");
if (img->trans != -1) {
for (i = 0; i < MAXCMSIZE; i++) {
if (i!=img->trans && colors[i].red == colors[img->trans].red) {
gray = false;
if (verbose > 1)
(void)fprintf(stderr,
"gif2png: transparent color is repeated in visible colors, using palette\n");
break;
}
}
}
}
bitdepth = 8;
if (last_color<16) bitdepth = 4;
if (last_color<4) bitdepth = 2;
if (last_color<2) bitdepth = 1;
if (gray) {
remapping = true;
for (i = 0; i < MAXCMSIZE; i++)
remap[i] = colors[i].red;
gray_bitdepth = 8;
/* try to adjust to 4-bit precision grayscale */
low_prec = true;
for (i = 0; i < MAXCMSIZE; i++) {
if ((remap[i]&0xf)*0x11 != remap[i]) {
low_prec = false;
break;
}
}
if (low_prec) {
for (i = 0; i < MAXCMSIZE; i++) {
remap[i] &= 0xf;
}
gray_bitdepth = 4;
}
/* try to adjust to 2-bit precision grayscale */
if (low_prec) {
for (i = 0; i < MAXCMSIZE; i++) {
if ((remap[i]&3)*5 != remap[i]) {
low_prec = false;
break;
}
}
}
if (low_prec) {
for (i = 0; i < MAXCMSIZE; i++) {
remap[i] &= 3;
}
gray_bitdepth = 2;
}
/* try to adjust to 1-bit precision grayscale */
if (low_prec) {
for (i = 0; i < MAXCMSIZE; i++) {
if ((remap[i]&1)*3 != remap[i]) {
low_prec = false;
break;
}
}
}
if (low_prec) {
for (i = 0; i < MAXCMSIZE; i++) {
remap[i] &= 1;
}
gray_bitdepth=1;
}
if (bitdepth<gray_bitdepth) {
gray = false; /* write palette file */
remapping = false;
} else {
bitdepth = gray_bitdepth;
}
}
if (verbose > 1)
(void)fprintf(stderr, "gif2png: %d colors used, highest color %d, %s, bitdepth %d\n",
colors_used, last_color, gray ? "gray":"palette", bitdepth);
if (verbose > 2)
for (i = 0; i <= last_color; i++) {
(void)fprintf(stderr, "(%3d, %3d, %3d)\n",
colors[i].red, colors[i].blue, colors[i].green);
}
if (setjmp(png_jmpbuf(png_ptr)) != 0) {
(void)fprintf(stderr, "gif2png: libpng returns fatal error condition\n");
(void)free(png_ptr);
(void)free(info_ptr);
return 1;
}
/* Create and initialize the png_struct with the desired error handler
* functions. If you want to use the default stderr and longjump method,
* you can supply NULL for the last three parameters. We also check that
* the library version is compatible with the one used at compile time,
* in case we are using dynamically linked libraries. REQUIRED.
*/
/*@-nullpass@*/
png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING,
(void *)NULL, NULL, NULL);
/*@=nullpass@*/
if (png_ptr == NULL)
return(2);
/* Allocate/initialize the image information data. REQUIRED */
info_ptr = png_create_info_struct(png_ptr);
if (info_ptr == NULL)
{
/*@i1@*/png_destroy_write_struct(&png_ptr, (png_infopp)NULL);
return(2);
}
/* if errtype is not 1, this was generated by fatal() */
if ((errtype = setjmp(png_jmpbuf(png_ptr))) != 0) {
png_destroy_write_struct(&png_ptr, &info_ptr);
return errtype;
}
/* use standard C streams */
png_init_io(png_ptr, fp);
if(optimize)
png_set_compression_level(png_ptr, Z_BEST_COMPRESSION);
if (gamma_srgb)
{
png_set_gAMA(png_ptr, info_ptr, 1./2.2);
#if (PNG_LIBPNG_VER > 96)
png_set_sRGB(png_ptr, info_ptr, PNG_sRGB_INTENT_PERCEPTUAL);
#endif
}
/* set basic image properties: width/height, type, bit depth, interlace */
if (interlaced == PNG_INTERLACE_LAST)
interlaced = current->imagestruct->interlace!=0 ? PNG_INTERLACE_ADAM7 : PNG_INTERLACE_NONE;
png_set_IHDR(png_ptr, info_ptr,
current->imagestruct->width, current->imagestruct->height,
bitdepth,
gray ? PNG_COLOR_TYPE_GRAY : PNG_COLOR_TYPE_PALETTE,
interlaced,
PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);
/* if the GIF specified an aspect ratio, turn it into a pHYs chunk */
if (GifScreen.AspectRatio != 0 && GifScreen.AspectRatio != 49)
png_set_pHYs(png_ptr, info_ptr,
GifScreen.AspectRatio+15, 64, PNG_RESOLUTION_UNKNOWN);
/* if the GIF specified an image offset, turn it into a oFFs chunk */
if (img->offset_x>0 && img->offset_y>0)
png_set_oFFs(png_ptr, info_ptr,
img->offset_x, img->offset_y, PNG_OFFSET_PIXEL);
if (GifScreen.Background > 0) { /* no background for palette entry 0 */
/* if the background color doesn't appear in local palette, we just
leave it out, if the pic is part of an animation, at least some will
use the global palette */
if (gray) {
if (is_gray(GifScreen.ColorMap[GifScreen.Background])) {
color16back.gray = remap[GifScreen.Background];
/*@-compdef@*/
png_set_bKGD(png_ptr, info_ptr, &color16back);
/*@=compdef@*/
}
} else {
for (i = 0; i < MAXCMSIZE; i++) {
if (GifScreen.ColorMap[GifScreen.Background].red == colors[i].red &&
GifScreen.ColorMap[GifScreen.Background].green == colors[i].green &&
GifScreen.ColorMap[GifScreen.Background].blue == colors[i].blue) {
if (last_color < i)
last_color = i;
color16back.index = (png_byte)i;
/*@-compdef@*/
png_set_bKGD(png_ptr, info_ptr, &color16back);
/*@=compdef@*/
break;
}
}
}
}
/* transparency handling */
if (img->trans != -1) {
if (gray) {
if (verbose > 2)
(void)fprintf(stderr,
"gif2png: handling grayscale transparency\n");
color16trans.gray = remap[img->trans];
/*@-nullpass -compdef@*/
png_set_tRNS(png_ptr, info_ptr, NULL, 0, &color16trans);
/*@=nullpass =compdef@*/
} else {
if (verbose > 2)
(void)fprintf(stderr,
"gif2png: handling palette transparency\n");
/* GRR NOTE: may be inconsistent with background-color logic (above) */
remapping = true;
for (i = 0; i < MAXCMSIZE; i++)
remap[i] = (byte)i;
remap[0] = (byte)img->trans;
remap[img->trans] = 0;
pal_trans[0] = 0;
/*@-nullpass@*/
png_set_tRNS(png_ptr, info_ptr, pal_trans, 1, NULL);
/*@=nullpass@*/
}
}
/* generate the PNG palette */
if (!gray) {
if (remapping) {
if (verbose > 2)
(void)fprintf(stderr, "Remapping palette...\n");
for (i = 0; i <= last_color; i++) {
pal_rgb[i].red = current->imagestruct->colors[remap[i]].red;
pal_rgb[i].green = current->imagestruct->colors[remap[i]].green;
pal_rgb[i].blue = current->imagestruct->colors[remap[i]].blue;
}
pltep = pal_rgb;
} else {
if (verbose > 2)
(void)fprintf(stderr, "Palette copied from GIF colors...\n");
pltep = current->imagestruct->colors;
}
png_set_PLTE(png_ptr, info_ptr, pltep, last_color+1);
if (verbose > 2) {
(void)fprintf(stderr,
"PNG palette generated with %d colors:\n",
last_color+1);
for (i = 0; i <= last_color; i++) {
(void)fprintf(stderr, "(%3d, %3d, %3d)\n",
pltep[i].red, pltep[i].blue, pltep[i].green);
}
}
}
/* generate histogram chunk for paletted images only */
if (histogram && !gray) {
hist_maxvalue = 0;
for (i = 0; i < MAXCMSIZE; i++)
if (count[i]>hist_maxvalue)
hist_maxvalue = count[i];
if (hist_maxvalue <= 65535) {
/* no scaling necessary */
for (i = 0; i < MAXCMSIZE; i++)
histogr[i] = (png_uint_16)count[i];
} else {
for (i = 0; i < MAXCMSIZE; i++)
if (count[i] != 0) {
histogr[i] = (png_uint_16)
#ifdef __GO32__
/* avoid using fpu instructions on djgpp, so we don't need emu387 */
(((long long)count[i]*65535)/hist_maxvalue);
#else
((double)count[i]*65535.0/hist_maxvalue);
#endif
if (histogr[i] == 0)
histogr[i] = 1;
} else {
histogr[i] = 0;
}
}
png_set_hIST(png_ptr, info_ptr, histogr);
}
/* transcribe software chunk if necessary */
/*@-observertrans -statictrans@ -unqualifiedtrans -branchstate*/
if (software_chunk) {
software.compression = PNG_TEXT_COMPRESSION_NONE;
software.key = "Software";
software.text = (char*)version;
software.text_length = strlen(software.text);
png_set_text(png_ptr, info_ptr, &software, 1);
}
/*@=observertrans =statictrans =unqualifiedtrans =branchstate@*/
png_write_info(png_ptr, info_ptr);
if (bitdepth<8)
png_set_packing(png_ptr);
/* loop over elements until we reach the image or the last element if
this is the last image in a GIF */
while(lastimg ? s != NULL : s != e->next) {
byte *data;
switch((byte)s->GIFtype) {
/*@-branchstate@*/
case GIFimage:
passcount = png_set_interlace_handling(png_ptr);
for (p = 0; p<passcount;p++)
for (i = 0; i < (int)current->imagestruct->height; i++) {
if (progress) {
if (passcount>1)
(void)fprintf(stderr, "%d/%d ", p+1, passcount);
(void)fprintf(stderr, "%2d%%\r",
(int)(((long)i*100)/current->imagestruct->height));
(void)fflush(stderr);
}
data = current->data +
(long) (img->interlace!=0 ?
interlace_line((int)current->imagestruct->height,i) : i) * current->imagestruct->width;
/* we have to remap once */
if (remapping && p == 0)
{
for (j = 0; j < (int)img->width; j++) {
data[j] = remap[data[j]];
}
}
png_write_row(png_ptr, data);
}
break;
case GIFcomment:
j = (int)s->size;
/* some GIF encoders produce trailing garbage and NULs */
if (j > 0 && ((s->data[j-1] == '\0') || (s->data[j-1] & 0x80)!=0))
--j;
/*@-observertrans -statictrans @*/
comment.key = "Comment";
if (j<500) {
comment.compression = PNG_TEXT_COMPRESSION_NONE;
} else {
comment.compression = PNG_TEXT_COMPRESSION_zTXt;
}
comment.text = (png_charp)s->data;
comment.text_length = strlen(comment.text);
png_set_text(png_ptr, info_ptr, &comment, 1);
/*@=observertrans =statictrans@*/
break;
case GIFapplication:
png_write_chunk_start(png_ptr,
(unsigned char *)"gIFx",
(png_uint_32)s->size);
png_write_chunk_data(png_ptr,
s->data,
(png_size_t)s->size);
png_write_chunk_end(png_ptr);
break;
/* Plain Text Extensions are not supported because they represent a separate
subimage, and PNG is explicitly a single-image format. PNG's gIFt chunk
has been officially deprecated.
*/
#if 0
case GIFplaintext:
/* gIFt is 12 bytes longer than GCE, due to 32-bit ints and
rgb colors */
png_write_chunk_start(png_ptr, "gIFt", s->size+12);
memset(buffer, 0, 24);
buffer[2] = s->data[1];
buffer[3] = s->data[0];
buffer[6] = s->data[3];
buffer[7] = s->data[2];
buffer[10] = s->data[5];
buffer[11] = s->data[4];
buffer[14] = s->data[7];
buffer[15] = s->data[6];
buffer[16] = s->data[8];
buffer[17] = s->data[9];
buffer[18] = GifScreen.ColorMap[s->data[10]].red;
buffer[19] = GifScreen.ColorMap[s->data[10]].green;
buffer[20] = GifScreen.ColorMap[s->data[10]].blue;
buffer[21] = GifScreen.ColorMap[s->data[11]].red;
buffer[22] = GifScreen.ColorMap[s->data[11]].green;
buffer[23] = GifScreen.ColorMap[s->data[11]].blue;
png_write_chunk_s->data(png_ptr, buffer, 24);
png_write_chunk_s->data(png_ptr, s->data+12, s->size-12);
png_write_chunk_end(png_ptr);
break;
#endif
case GIFgraphicctl:
buffer[0] = (s->data[0] >> 2) & 7;
buffer[1] = (s->data[0] >> 1) & 1;
buffer[2] = s->data[2];
buffer[3] = s->data[1];
png_write_chunk(png_ptr, (unsigned char *)"gIFg", buffer, 4);
break;
default:
(void)fprintf(stderr,
"gif2png internal error: encountered unused element type %c\n",
s->GIFtype);
break;
}
/*@=branchstate@*/
s = s->next;
}
png_write_end(png_ptr, info_ptr);
/* clean up after the write, and free any memory allocated */
png_destroy_write_struct(&png_ptr, &info_ptr);
return errorcount;
}
/*@=globstate =mustfreefresh@*/
/*@-onlytrans@*/
int
MatteGIF(GifColor matte)
/* convert transparent pixels to a matte of given color */
{
int icount = 0;
/* apply matte color to image-local transparency values */
for (current = &first; current ; current = current->next) {
if (current->imagestruct) {
if (current->imagestruct->trans == -1)
(void)fprintf(stderr,
"gif2png: no transparency color in image %d, matte argument ignored\n",
icount);
else {
if (verbose > 0) {
(void)fprintf(stderr,
"gif2png: transparent value in image %d is %d\n",
icount, current->imagestruct->trans);
}
current->imagestruct->colors[current->imagestruct->trans] = matte;
current->imagestruct->trans = -1;
}
}
}
return icount;
}
/*@=onlytrans@*/
/*@-onlytrans@*/
static int processfilter(void)
{
int num_pics;
struct GIFelement *start;
current = &first;
num_pics = ReadGIF (stdin);
(void)fclose(stdin);
if (num_pics != 1) {
(void)fprintf(stderr,
"gif2png: %d images in -f (filter) mode\n", num_pics);
return 1;
}
/* eliminate use of transparency, if that is called for */
if (matte)
(void)MatteGIF(matte_color);
start = NULL;
for (current = first.next; current ; current = current->next) {
if (start == NULL) start = current;
if (current->GIFtype == GIFimage) {
(void)writefile(start, current, stdout, true);
start = NULL;
++numpngs;
}
}
free_mem();
return 0;
}
/*@=onlytrans@*/
/*@-onlytrans@*/
static int processfile(char *fname, FILE *fp)
{
char outname[1025]; /* MAXPATHLEN comes under too many names */
int num_pics;
struct GIFelement *start;
int i;
bool suppress_delete = false;
char *file_ext;
struct utimbuf time_buf;
if (fp == NULL) return 1;
current = &first;
num_pics = ReadGIF (fp);
if (preserve_mtime)
{
struct stat stat_buf;
/*@-compdef@*/
/*@-unrecog@*//* needed because splint's POSIX library is buggy */
if (fstat(fileno(fp), &stat_buf) < 0)
{
perror("Could not get input file times");
return 1;
}
/*@=compdef@*/
/*@-usedef@*/
time_buf.actime = stat_buf.st_atime;
time_buf.modtime = stat_buf.st_mtime;
/*@=usedef@*/
}
(void)fclose(fp);
if (num_pics >= 0 && verbose > 1)
(void)fprintf(stderr, "gif2png: number of images %d\n", num_pics);
if (num_pics <= 0)
return 1;
if (webconvert) {
if (num_pics != 1)
{
(void)fprintf(stderr, "gif2png: %s is multi-image\n", fname);
return 0;
}
else
{
(void)printf("%s\n", fname);
return 0;
}
}
/* eliminate use of transparency, if that is called for */
if (matte)
(void)MatteGIF(matte_color);
/* create output filename */
(void)strcpy(outname, fname);
file_ext = outname+strlen(outname);
if (file_ext >= outname + 4)
file_ext -= 4;
if (strcmp(file_ext, ".gif") != 0 && strcmp(file_ext, ".GIF") != 0 &&
strcmp(file_ext, "_gif") != 0 && strcmp(file_ext, "_GIF") != 0) {
/* try to derive basename */
file_ext = outname+strlen(outname);
while(file_ext >= outname) {
if (*file_ext == '.' || *file_ext == '/' || *file_ext == '\\') break;
file_ext--;
}
if (file_ext<outname || *file_ext != '.') {
/* as a last resort, just add .png to the filename */
file_ext = outname+strlen(outname);
}
}
(void)strcpy(file_ext, ".png"); /* images are named .png, .p01, .p02, ... */
start = NULL;
i = 0;
for (current = first.next; current ; current = current->next) {
if (start == NULL) start = current;
if (current->GIFtype == GIFimage) {
i++;
if ((fp = fopen(outname, "wb")) == NULL) {
perror(outname);
return 1;
} else {
suppress_delete |= writefile(start, current, fp, i == num_pics);
(void)fclose(fp);
if (preserve_mtime)
{
/*@-compdef@*/
if (utime(outname, &time_buf) < 0)
{
perror("Could not set output file times");
return 1;
}
/*@=compdef@*/
}
++numpngs;
start = NULL;
/*@-bufferoverflowhigh*/
(void)sprintf(file_ext, ".p%02d", i);
/*@=bufferoverflowhigh*/
}
}
}
free_mem();
if (delete && !suppress_delete) {
(void)unlink(fname);
}
return 0;
}
/*@=onlytrans@*/
/* check if stdin is a terminal, if your compiler is lacking isatty or fileno
(non-ANSI functions), just return false
*/
static bool input_is_terminal(void)
{
return isatty(fileno(stdin))!=0;
}
int main(int argc, char *argv[])
{
FILE *fp;
int i;
unsigned int background;
int errors = 0;
char name[1025];
int ac;
char *color;
software_chunk = true;
for (ac = 1; ac < argc && argv[ac][0] == '-'; ac++)
{
for (i = 1; i < (int)strlen(argv[ac]); i++)
switch(argv[ac][i]) {
case 'b':
if (ac >= argc - 1)
{
(void)fputs("gif2png: missing background-matte argument\n",
stderr);
exit(1);
}
color = argv[++ac];
if (*color == '#')
color++;
(void)sscanf(color, "%ux", &background);
matte_color.red = (background >> 16) & 0xff;
matte_color.green = (background >> 8) & 0xff;
matte_color.blue = background & 0xff;
matte = true;
goto skiparg;
case 'd':
delete = true;
break;
case 'f':
case '1': /* backward compatibility */
filtermode = true;
break;
case 'g':
gamma_srgb = true;
break;
case 'h':
histogram = true;
break;
case 'i':
interlaced = PNG_INTERLACE_ADAM7;
break;
case 'm':
preserve_mtime = true;
break;
case 'n':
interlaced = PNG_INTERLACE_NONE;
break;
case 'p':
progress = true;
break;
case 'r':
recover = true;
break;
case 's':
software_chunk = false;
break;
case 'v':
++verbose;
break;
case 'w':
webconvert = true;
break;
case 'O':
optimize = true;
break;
default:
(void)fprintf(stderr,
"gif2png: unknown option `-%c'\n", argv[ac][i]);
usage:
(void)fprintf(stderr,
"\n"
"usage: gif2png [ -bdfghinprstvwO ] [file[.gif]] ...\n"
"\n"
" -b replace background pels with given RRGGBB color (hex digits)\n"
" -d delete source GIF files after successful conversion\n"
" -f allow use as filter, die on multi-image GIF\n"
" -g write gamma=(1.0/2.2) and sRGB chunks\n"
" -h generate PNG histogram chunks into color output files\n"
" -i force conversion to interlaced PNG files\n"
" -m preserve input file modification time\n"
" -n force conversion to noninterlaced PNG files\n"
" -p display progress of PNG writing in %%\n"
" -r try to recover corrupted GIF files\n"
" -s do not write Software text chunk\n"
" -v verbose; display conversion statistics and debugging messages\n"
" -w web probe, list images without animation or transparency\n"
" -O optimize; remove unused color-table entries; use zlib level 9\n"
" -1 one-only; same as -f; provided for backward compatibility\n"
"\n"
" If no source files are listed, stdin is converted to noname.png.\n"
"\n"
" This is %s, %s\n", version, compile_info);
return 1;
}
skiparg:;
}
if (verbose > 1)
(void)fprintf(stderr, "gif2png: %s, %s\n", version, compile_info);
/* loop over arguments or use stdin */
if (argc == ac) {
if (input_is_terminal()) {
goto usage;
}
if (verbose > 1)
(void)fprintf(stderr, "stdin:\n");
if (filtermode) {
if (processfilter() != 0) ++errors;
} else {
(void)processfile("noname.gif", stdin);
++numgifs;
}
} else {
for (i = ac;i<argc; i++) {
/* make sure that there is enough space for a '.p<NUM>' suffix;
this check catches also the '.gif' case below. */
if (strlen(argv[i]) >= sizeof name - sizeof ".p" - 3 * sizeof(int)) {
(void)fprintf(stderr, "%s: name too long\n", argv[i]);
errors = 1;
continue;
}
(void)strcpy(name, argv[i]);
if ((fp = fopen(name, "rb")) == NULL) {
/* retry with .gif appended */
(void)strcat(name, ".gif");
fp = fopen(name,"rb");
}
if (fp == NULL) {
perror(argv[i]);
errors = 1;
} else {
if (verbose > 1)
(void)fprintf(stderr, "%s:\n", name);
errors |= processfile(name, fp);
/* fp is closed in processfile */
++numgifs;
}
}
}
if (verbose > 0)
(void)fprintf(stderr, "Done (%s). Converted %ld GIF%s into %ld PNG%s.\n",
errors!=0? "with one or more errors" : "no errors detected",
numgifs, (numgifs == 1) ? "" : "s", numpngs, (numpngs == 1)? "" : "s");
return errors;
}
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