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Guy Schalnat 1995-09-26 05:22:39 -05:00 committed by Glenn Randers-Pehrson
parent 0d5805822f
commit 51f0eb4584
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488
ansi2knr.c
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@ -1,488 +0,0 @@
/* Copyright (C) 1989, 1991, 1993 Aladdin Enterprises. All rights reserved. */
/* ansi2knr.c */
/* Convert ANSI function declarations to K&R syntax */
/*
ansi2knr is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY. No author or distributor accepts responsibility
to anyone for the consequences of using it or for whether it serves any
particular purpose or works at all, unless he says so in writing. Refer
to the GNU General Public License for full details.
Everyone is granted permission to copy, modify and redistribute
ansi2knr, but only under the conditions described in the GNU
General Public License. A copy of this license is supposed to have been
given to you along with ansi2knr so you can know your rights and
responsibilities. It should be in a file named COPYING. Among other
things, the copyright notice and this notice must be preserved on all
copies.
*/
/*
---------- Here is the GNU GPL file COPYING, referred to above ----------
----- These terms do NOT apply to the JPEG software itself; see README ------
GHOSTSCRIPT GENERAL PUBLIC LICENSE
(Clarified 11 Feb 1988)
Copyright (C) 1988 Richard M. Stallman
Everyone is permitted to copy and distribute verbatim copies of this
license, but changing it is not allowed. You can also use this wording
to make the terms for other programs.
The license agreements of most software companies keep you at the
mercy of those companies. By contrast, our general public license is
intended to give everyone the right to share Ghostscript. To make sure
that you get the rights we want you to have, we need to make
restrictions that forbid anyone to deny you these rights or to ask you
to surrender the rights. Hence this license agreement.
Specifically, we want to make sure that you have the right to give
away copies of Ghostscript, that you receive source code or else can get
it if you want it, that you can change Ghostscript or use pieces of it
in new free programs, and that you know you can do these things.
To make sure that everyone has such rights, we have to forbid you to
deprive anyone else of these rights. For example, if you distribute
copies of Ghostscript, you must give the recipients all the rights that
you have. You must make sure that they, too, receive or can get the
source code. And you must tell them their rights.
Also, for our own protection, we must make certain that everyone finds
out that there is no warranty for Ghostscript. If Ghostscript is
modified by someone else and passed on, we want its recipients to know
that what they have is not what we distributed, so that any problems
introduced by others will not reflect on our reputation.
Therefore we (Richard M. Stallman and the Free Software Foundation,
Inc.) make the following terms which say what you must do to be allowed
to distribute or change Ghostscript.
COPYING POLICIES
1. You may copy and distribute verbatim copies of Ghostscript source
code as you receive it, in any medium, provided that you conspicuously
and appropriately publish on each copy a valid copyright and license
notice "Copyright (C) 1989 Aladdin Enterprises. All rights reserved.
Distributed by Free Software Foundation, Inc." (or with whatever year is
appropriate); keep intact the notices on all files that refer to this
License Agreement and to the absence of any warranty; and give any other
recipients of the Ghostscript program a copy of this License Agreement
along with the program. You may charge a distribution fee for the
physical act of transferring a copy.
2. You may modify your copy or copies of Ghostscript or any portion of
it, and copy and distribute such modifications under the terms of
Paragraph 1 above, provided that you also do the following:
a) cause the modified files to carry prominent notices stating
that you changed the files and the date of any change; and
b) cause the whole of any work that you distribute or publish,
that in whole or in part contains or is a derivative of Ghostscript
or any part thereof, to be licensed at no charge to all third
parties on terms identical to those contained in this License
Agreement (except that you may choose to grant more extensive
warranty protection to some or all third parties, at your option).
c) You may charge a distribution fee for the physical act of
transferring a copy, and you may at your option offer warranty
protection in exchange for a fee.
Mere aggregation of another unrelated program with this program (or its
derivative) on a volume of a storage or distribution medium does not bring
the other program under the scope of these terms.
3. You may copy and distribute Ghostscript (or a portion or derivative
of it, under Paragraph 2) in object code or executable form under the
terms of Paragraphs 1 and 2 above provided that you also do one of the
following:
a) accompany it with the complete corresponding machine-readable
source code, which must be distributed under the terms of
Paragraphs 1 and 2 above; or,
b) accompany it with a written offer, valid for at least three
years, to give any third party free (except for a nominal
shipping charge) a complete machine-readable copy of the
corresponding source code, to be distributed under the terms of
Paragraphs 1 and 2 above; or,
c) accompany it with the information you received as to where the
corresponding source code may be obtained. (This alternative is
allowed only for noncommercial distribution and only if you
received the program in object code or executable form alone.)
For an executable file, complete source code means all the source code for
all modules it contains; but, as a special exception, it need not include
source code for modules which are standard libraries that accompany the
operating system on which the executable file runs.
4. You may not copy, sublicense, distribute or transfer Ghostscript
except as expressly provided under this License Agreement. Any attempt
otherwise to copy, sublicense, distribute or transfer Ghostscript is
void and your rights to use the program under this License agreement
shall be automatically terminated. However, parties who have received
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5. If you wish to incorporate parts of Ghostscript into other free
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Software Foundation at 675 Mass Ave, Cambridge, MA 02139. We have not
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status of all derivatives of our free software and of promoting the
sharing and reuse of software.
Your comments and suggestions about our licensing policies and our
software are welcome! Please contact the Free Software Foundation,
Inc., 675 Mass Ave, Cambridge, MA 02139, or call (617) 876-3296.
NO WARRANTY
BECAUSE GHOSTSCRIPT IS LICENSED FREE OF CHARGE, WE PROVIDE ABSOLUTELY
NO WARRANTY, TO THE EXTENT PERMITTED BY APPLICABLE STATE LAW. EXCEPT
WHEN OTHERWISE STATED IN WRITING, FREE SOFTWARE FOUNDATION, INC, RICHARD
M. STALLMAN, ALADDIN ENTERPRISES, L. PETER DEUTSCH, AND/OR OTHER PARTIES
PROVIDE GHOSTSCRIPT "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER
EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE
ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF GHOSTSCRIPT IS WITH
YOU. SHOULD GHOSTSCRIPT PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL
NECESSARY SERVICING, REPAIR OR CORRECTION.
IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW WILL RICHARD M.
STALLMAN, THE FREE SOFTWARE FOUNDATION, INC., L. PETER DEUTSCH, ALADDIN
ENTERPRISES, AND/OR ANY OTHER PARTY WHO MAY MODIFY AND REDISTRIBUTE
GHOSTSCRIPT AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING
ANY LOST PROFITS, LOST MONIES, OR OTHER SPECIAL, INCIDENTAL OR
CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE
(INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED
INACCURATE OR LOSSES SUSTAINED BY THIRD PARTIES OR A FAILURE OF THE
PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS) GHOSTSCRIPT, EVEN IF YOU
HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES, OR FOR ANY CLAIM
BY ANY OTHER PARTY.
-------------------- End of file COPYING ------------------------------
*/
#include <stdio.h>
#include <ctype.h>
#ifdef BSD
#include <strings.h>
#else
#ifdef VMS
extern int strlen(), strncmp();
#else
#include <string.h>
#endif
#endif
/* malloc and free should be declared in stdlib.h, */
/* but if you've got a K&R compiler, they probably aren't. */
#ifdef MSDOS
#include <malloc.h>
#else
#ifdef VMS
extern char *malloc();
extern void free();
#else
extern char *malloc();
extern int free();
#endif
#endif
/* Usage:
ansi2knr input_file [output_file]
* If no output_file is supplied, output goes to stdout.
* There are no error messages.
*
* ansi2knr recognizes functions by seeing a non-keyword identifier
* at the left margin, followed by a left parenthesis,
* with a right parenthesis as the last character on the line.
* It will recognize a multi-line header provided that the last character
* of the last line of the header is a right parenthesis,
* and no intervening line ends with a left brace or a semicolon.
* These algorithms ignore whitespace and comments, except that
* the function name must be the first thing on the line.
* The following constructs will confuse it:
* - Any other construct that starts at the left margin and
* follows the above syntax (such as a macro or function call).
* - Macros that tinker with the syntax of the function header.
*/
/* Scanning macros */
#define isidchar(ch) (isalnum(ch) || (ch) == '_')
#define isidfirstchar(ch) (isalpha(ch) || (ch) == '_')
/* Forward references */
char *skipspace();
int writeblanks();
int test1();
int convert1();
/* The main program */
main(argc, argv)
int argc;
char *argv[];
{ FILE *in, *out;
#define bufsize 5000 /* arbitrary size */
char *buf;
char *line;
switch ( argc )
{
default:
printf("Usage: ansi2knr input_file [output_file]\n");
exit(0);
case 2:
out = stdout; break;
case 3:
out = fopen(argv[2], "w");
if ( out == NULL )
{ fprintf(stderr, "Cannot open %s\n", argv[2]);
exit(1);
}
}
in = fopen(argv[1], "r");
if ( in == NULL )
{ fprintf(stderr, "Cannot open %s\n", argv[1]);
exit(1);
}
fprintf(out, "#line 1 \"%s\"\n", argv[1]);
buf = malloc(bufsize);
line = buf;
while ( fgets(line, (unsigned)(buf + bufsize - line), in) != NULL )
{ switch ( test1(buf) )
{
case 1: /* a function */
convert1(buf, out);
break;
case -1: /* maybe the start of a function */
line = buf + strlen(buf);
if ( line != buf + (bufsize - 1) ) /* overflow check */
continue;
/* falls through */
default: /* not a function */
fputs(buf, out);
break;
}
line = buf;
}
if ( line != buf ) fputs(buf, out);
free(buf);
fclose(out);
fclose(in);
return 0;
}
/* Skip over space and comments, in either direction. */
char *
skipspace(p, dir)
register char *p;
register int dir; /* 1 for forward, -1 for backward */
{ for ( ; ; )
{ while ( isspace(*p) ) p += dir;
if ( !(*p == '/' && p[dir] == '*') ) break;
p += dir; p += dir;
while ( !(*p == '*' && p[dir] == '/') )
{ if ( *p == 0 ) return p; /* multi-line comment?? */
p += dir;
}
p += dir; p += dir;
}
return p;
}
/*
* Write blanks over part of a string.
*/
int
writeblanks(start, end)
char *start;
char *end;
{ char *p;
for ( p = start; p < end; p++ ) *p = ' ';
return 0;
}
/*
* Test whether the string in buf is a function definition.
* The string may contain and/or end with a newline.
* Return as follows:
* 0 - definitely not a function definition;
* 1 - definitely a function definition;
* -1 - may be the beginning of a function definition,
* append another line and look again.
*/
int
test1(buf)
char *buf;
{ register char *p = buf;
char *bend;
char *endfn;
int contin;
if ( !isidfirstchar(*p) )
return 0; /* no name at left margin */
bend = skipspace(buf + strlen(buf) - 1, -1);
switch ( *bend )
{
case ')': contin = 1; break;
case '{':
case ';': return 0; /* not a function */
default: contin = -1;
}
while ( isidchar(*p) ) p++;
endfn = p;
p = skipspace(p, 1);
if ( *p++ != '(' )
return 0; /* not a function */
p = skipspace(p, 1);
if ( *p == ')' )
return 0; /* no parameters */
/* Check that the apparent function name isn't a keyword. */
/* We only need to check for keywords that could be followed */
/* by a left parenthesis (which, unfortunately, is most of them). */
{ static char *words[] =
{ "asm", "auto", "case", "char", "const", "double",
"extern", "float", "for", "if", "int", "long",
"register", "return", "short", "signed", "sizeof",
"static", "switch", "typedef", "unsigned",
"void", "volatile", "while", 0
};
char **key = words;
char *kp;
int len = endfn - buf;
while ( (kp = *key) != 0 )
{ if ( strlen(kp) == len && !strncmp(kp, buf, len) )
return 0; /* name is a keyword */
key++;
}
}
return contin;
}
int
convert1(buf, out)
char *buf;
FILE *out;
{ char *endfn;
register char *p;
char **breaks;
unsigned num_breaks = 2; /* for testing */
char **btop;
char **bp;
char **ap;
/* Pre-ANSI implementations don't agree on whether strchr */
/* is called strchr or index, so we open-code it here. */
for ( endfn = buf; *(endfn++) != '('; ) ;
top: p = endfn;
breaks = (char **)malloc(sizeof(char *) * num_breaks * 2);
if ( breaks == 0 )
{ /* Couldn't allocate break table, give up */
fprintf(stderr, "Unable to allocate break table!\n");
fputs(buf, out);
return -1;
}
btop = breaks + num_breaks * 2 - 2;
bp = breaks;
/* Parse the argument list */
do
{ int level = 0;
char *end = NULL;
if ( bp >= btop )
{ /* Filled up break table. */
/* Allocate a bigger one and start over. */
free((char *)breaks);
num_breaks <<= 1;
goto top;
}
*bp++ = p;
/* Find the end of the argument */
for ( ; end == NULL; p++ )
{ switch(*p)
{
case ',': if ( !level ) end = p; break;
case '(': level++; break;
case ')': if ( --level < 0 ) end = p; break;
case '/': p = skipspace(p, 1) - 1; break;
default: ;
}
}
p--; /* back up over terminator */
/* Find the name being declared. */
/* This is complicated because of procedure and */
/* array modifiers. */
for ( ; ; )
{ p = skipspace(p - 1, -1);
switch ( *p )
{
case ']': /* skip array dimension(s) */
case ')': /* skip procedure args OR name */
{ int level = 1;
while ( level )
switch ( *--p )
{
case ']': case ')': level++; break;
case '[': case '(': level--; break;
case '/': p = skipspace(p, -1) + 1; break;
default: ;
}
}
if ( *p == '(' && *skipspace(p + 1, 1) == '*' )
{ /* We found the name being declared */
while ( !isidfirstchar(*p) )
p = skipspace(p, 1) + 1;
goto found;
}
break;
default: goto found;
}
}
found: if ( *p == '.' && p[-1] == '.' && p[-2] == '.' )
{ p++;
if ( bp == breaks + 1 ) /* sole argument */
writeblanks(breaks[0], p);
else
writeblanks(bp[-1] - 1, p);
bp--;
}
else
{ while ( isidchar(*p) ) p--;
*bp++ = p+1;
}
p = end;
}
while ( *p++ == ',' );
*bp = p;
/* Make a special check for 'void' arglist */
if ( bp == breaks+2 )
{ p = skipspace(breaks[0], 1);
if ( !strncmp(p, "void", 4) )
{ p = skipspace(p+4, 1);
if ( p == breaks[2] - 1 )
{ bp = breaks; /* yup, pretend arglist is empty */
writeblanks(breaks[0], p + 1);
}
}
}
/* Put out the function name */
p = buf;
while ( p != endfn ) putc(*p, out), p++;
/* Put out the declaration */
for ( ap = breaks+1; ap < bp; ap += 2 )
{ p = *ap;
while ( isidchar(*p) ) putc(*p, out), p++;
if ( ap < bp - 1 ) fputs(", ", out);
}
fputs(") ", out);
/* Put out the argument declarations */
for ( ap = breaks+2; ap <= bp; ap += 2 ) (*ap)[-1] = ';';
fputs(breaks[0], out);
free((char *)breaks);
return 0;
}

63
example.c
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@ -6,6 +6,10 @@
designed to be a starting point of an implementation. designed to be a starting point of an implementation.
This is not officially part of libpng, and therefore This is not officially part of libpng, and therefore
does not require a copyright notice. does not require a copyright notice.
This file does not currently compile, because it is missing
certain parts, like allocating memory to hold an image.
You will have to supply these parts to get it to compile.
*/ */
#include <png.h> #include <png.h>
@ -81,15 +85,11 @@ void read_png(char *file_name)
/* read the file information */ /* read the file information */
png_read_info(png_ptr, info_ptr); png_read_info(png_ptr, info_ptr);
/* allocate the memory to hold the image using the fields
of png_info. */
/* set up the transformations you want. Note that these are /* set up the transformations you want. Note that these are
all optional. Only call them if you want them */ all optional. Only call them if you want them */
/* expand paletted colors into true rgb */ /* expand paletted colors into true rgb */
if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE && if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
info_ptr->bit_depth < 8)
png_set_expand(png_ptr); png_set_expand(png_ptr);
/* expand grayscale images to the full 8 bits */ /* expand grayscale images to the full 8 bits */
@ -163,26 +163,32 @@ void read_png(char *file_name)
if (info_ptr->bit_depth == 16) if (info_ptr->bit_depth == 16)
png_set_swap(png_ptr); png_set_swap(png_ptr);
/* add a filler byte to store rgb files as rgbx */ /* add a filler byte to rgb files */
if (info_ptr->bit_depth == 8 && if (info_ptr->bit_depth == 8 &&
info_ptr->color_type == PNG_COLOR_TYPE_RGB) info_ptr->color_type == PNG_COLOR_TYPE_RGB)
png_set_rgbx(png_ptr); png_set_filler(png_ptr, 0xff, PNG_FILLER_AFTER);
/* optional call to update palette with transformations */ /* turn on interlace handling if you are not using png_read_image() */
png_start_read_image(png_ptr);
/* the easiest way to read the image */
void *row_pointers[height];
png_read_image(png_ptr, row_pointers);
/* the other way to read images - deal with interlacing */
/* turn on interlace handling */
if (info_ptr->interlace_type) if (info_ptr->interlace_type)
number_passes = png_set_interlace_handling(png_ptr); number_passes = png_set_interlace_handling(png_ptr);
else else
number_passes = 1; number_passes = 1;
/* optional call to update palette with transformations */
png_start_read_image(png_ptr);
/* optional call to update the info structure */
png_read_update_info(png_ptr, info_ptr);
/* allocate the memory to hold the image using the fields
of png_info. */
/* the easiest way to read the image */
png_bytef *row_pointers[height];
png_read_image(png_ptr, row_pointers);
/* the other way to read images - deal with interlacing */
for (pass = 0; pass < number_passes; pass++) for (pass = 0; pass < number_passes; pass++)
{ {
/* Read the image using the "sparkle" effect. */ /* Read the image using the "sparkle" effect. */
@ -191,7 +197,7 @@ void read_png(char *file_name)
/* If you are only reading on row at a time, this works */ /* If you are only reading on row at a time, this works */
for (y = 0; y < height; y++) for (y = 0; y < height; y++)
{ {
char *row_pointers = row[y]; png_bytef *row_pointers = row[y];
png_read_rows(png_ptr, &row_pointers, NULL, 1); png_read_rows(png_ptr, &row_pointers, NULL, 1);
} }
@ -309,21 +315,22 @@ void write_png(char *file_name, ... other image information ...)
/* swap bytes of 16 bit files to most significant bit first */ /* swap bytes of 16 bit files to most significant bit first */
png_set_swap(png_ptr); png_set_swap(png_ptr);
/* get rid of filler bytes, pack rgb into 3 bytes */ /* get rid of filler bytes, pack rgb into 3 bytes. The
png_set_rgbx(png_ptr); filler number is not used. */
png_set_filler(png_ptr, 0, PNG_FILLER_BEFORE);
/* the easiest way to write the image */ /* turn on interlace handling if you are not using png_write_image() */
void *row_pointers[height];
png_write_image(png_ptr, row_pointers);
/* the other way to write the image - deal with interlacing */
/* turn on interlace handling */
if (interlacing) if (interlacing)
number_passes = png_set_interlace_handling(png_ptr); number_passes = png_set_interlace_handling(png_ptr);
else else
number_passes = 1; number_passes = 1;
/* the easiest way to write the image */
png_bytef *row_pointers[height];
png_write_image(png_ptr, row_pointers);
/* the other way to write the image - deal with interlacing */
for (pass = 0; pass < number_passes; pass++) for (pass = 0; pass < number_passes; pass++)
{ {
/* Write a few rows at a time. */ /* Write a few rows at a time. */
@ -332,7 +339,7 @@ void write_png(char *file_name, ... other image information ...)
/* If you are only writing one row at a time, this works */ /* If you are only writing one row at a time, this works */
for (y = 0; y < height; y++) for (y = 0; y < height; y++)
{ {
char *row_pointers = row[y]; png_bytef *row_pointers = row[y];
png_write_rows(png_ptr, &row_pointers, 1); png_write_rows(png_ptr, &row_pointers, 1);
} }
} }

82
libpng.txt
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@ -1,9 +1,9 @@
libpng.txt - a description on how to use and modify libpng libpng.txt - a description on how to use and modify libpng
libpng 1.0 beta 1 - version 0.71 libpng 1.0 beta 2 - version 0.8
For conditions of distribution and use, see copyright notice in png.h For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc. Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
June 26, 1995 August 20, 1995
This file describes how to use and modify the PNG reference library This file describes how to use and modify the PNG reference library
(known as libpng) for your own use. There are four sections to this (known as libpng) for your own use. There are four sections to this
@ -325,17 +325,21 @@ PC's store them, for example), call this:
png_set_swap(png_ptr); png_set_swap(png_ptr);
PNG files store rgb pixels packed into 3 bytes. If you would rather PNG files store rgb pixels packed into 3 bytes. If you would rather
pack them into 4 bytes, with the filler byte last, call this: pack them into 4 bytes, call this:
if (info_ptr->bit_depth == 8 && if (info_ptr->bit_depth == 8 &&
info_ptr->color_type == PNG_COLOR_TYPE_RGB) info_ptr->color_type == PNG_COLOR_TYPE_RGB)
png_set_rgbx(png_ptr); png_set_filler(png_ptr, filler_byte, PNG_FILLER_BEFORE);
If you need the filler byte first, call this: where filler_byte is the number to fill with, and the location is
either PNG_FILLER_BEFORE or PNG_FILLER_AFTER, depending upon whether
you want the filler before the rgb or after.
if (info_ptr->bit_depth == 8 && Finally, if you need the interlacing as discussed below, call
info_ptr->color_type == PNG_COLOR_TYPE_RGB) this here:
png_set_xrgb(png_ptr);
if (info_ptr->interlace_type)
number_passes = png_set_interlace_handling(png_ptr);
After setting the transformations, you can update your palette by After setting the transformations, you can update your palette by
calling png_start_read_image(). This function is provided for those calling png_start_read_image(). This function is provided for those
@ -345,7 +349,22 @@ before it reads the first row.
png_start_read_image(png_ptr); png_start_read_image(png_ptr);
That's it for the transformations. Now you can read the image data. If you want, libpng will update your png_info structure to reflect
any transformations you've requested with this call. This is most
useful to update the info structures rowbytes field, so you can
use it to allocate your image memory. This function calls
png_start_read_image(), so you don't have to call both of them.
png_read_update_info(png_ptr, info_ptr);
After you call png_read_update_info(), you can allocate any
memory you need to hold the image. As the actual allocation
varies among applications, no example will be given. If you
are allocating one large chunk, you may find it useful to
build an array of pointers to each row, as it will be needed
for some of the functions below.
After you've allocated memory, you can read the image data.
The simplest way to do this is in one function call. If you are The simplest way to do this is in one function call. If you are
allocating enough memory to hold the whole image, you can just allocating enough memory to hold the whole image, you can just
call png_read_image() and libpng will read in all the image data call png_read_image() and libpng will read in all the image data
@ -399,7 +418,7 @@ call png_read_rows() the correct number of times to read in all
seven images. See the PNG specification for more details on the seven images. See the PNG specification for more details on the
interlacing scheme. interlacing scheme.
If you want libpng to expand the images, call this: If you want libpng to expand the images, call this above:
if (info_ptr->interlace_type) if (info_ptr->interlace_type)
number_passes = png_set_interlace_handling(png_ptr); number_passes = png_set_interlace_handling(png_ptr);
@ -521,6 +540,25 @@ Customizing Libpng section below.
png_init_io(png_ptr, fp); png_init_io(png_ptr, fp);
You now have the option of modifying how the compression library
will run. The following functions are mainly for testing, but
may be useful in certain special cases, like if you need to
write png files extremely fast and are willing to give up some
compression, or if you want to get the maximum possible compression
at the expense of slower writing. If you have no special needs
in this area, let the library do what it wants, as it has been
carefully tuned to deliver the best speed/compression ratio.
See the compression library for more details.
/* turn on or off filtering (1 or 0) */
png_set_filtering(png_struct *png_ptr, 1);
png_set_compression_level(png_ptr, Z_DEFAULT_COMPRESSION);
png_set_compression_mem_level(png_ptr, 8);
png_set_compression_strategy(png_ptr, Z_DEFAULT_STRATEGY);
png_set_compression_window_bits(png_ptr, 15);
png_set_compression_method(png_ptr, 8);
You now need to fill in the png_info structure with all the data You now need to fill in the png_info structure with all the data
you wish to write before the actual image. Note that the only thing you wish to write before the actual image. Note that the only thing
you are allowed to write after the image is the text chunks and the you are allowed to write after the image is the text chunks and the
@ -600,14 +638,13 @@ make sure to only enable a transformation if it will be valid for
the data. For example, don't swap red and blue on grayscale data. the data. For example, don't swap red and blue on grayscale data.
PNG files store rgb pixels packed into 3 bytes. If you would rather PNG files store rgb pixels packed into 3 bytes. If you would rather
supply the pixels as 4 bytes per pixel, with the filler byte last, supply the pixels as 4 bytes per pixel, call this:
call this:
png_set_rgbx(png_ptr); png_set_filler(png_ptr, 0, PNG_FILLER_BEFORE);
If your filler byte goes first, call this: where the 0 is not used for writing, and the location is either
PNG_FILLER_BEFORE or PNG_FILLER_AFTER, depending upon whether you
png_set_xrgb(png_ptr); want the filler before the rgb or after.
PNG files pack pixels of bit depths 1, 2, and 4 into bytes as small as PNG files pack pixels of bit depths 1, 2, and 4 into bytes as small as
they can, resulting in, for example, 8 pixels per byte for 1 bit files. they can, resulting in, for example, 8 pixels per byte for 1 bit files.
@ -819,3 +856,16 @@ needed outside libpng are protected by the PNG_INTERNAL definition,
which is only defined for those routines inside libpng itself. The which is only defined for those routines inside libpng itself. The
files in libpng proper only include png.h. files in libpng proper only include png.h.
Removing unwanted object code:
There are a bunch of #define's in png.h that control what parts of
libpng are compiled. All the defines end in _SUPPORT. If you are
not using an ability, you can change the #define to #undef and
save yourself code and data space. All the reading and writing
specific code are in seperate files, so the linker should only grab
the files it needs. However, if you want to make sure, or if you
are building a stand alone library, all the reading files start with
pngr and all the writing files start with pngw. The files that
don't match either (like png.c, pngtrans.c, etc.) are used for
both reading and writing, and always need to be included.

43
makefile
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@ -2,18 +2,19 @@
# Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc. # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
# For conditions of distribution and use, see copyright notice in png.h # For conditions of distribution and use, see copyright notice in png.h
CC=gcc CC=cc
CFLAGS=-I../zlib -O3 CFLAGS=-I../zlib -O
LDFLAGS=-L. -L../zlib/ -lpng -lgz -lm LDFLAGS=-L. -L../zlib/ -lpng -lz -lm
RANLIB=ranlib #RANLIB=ranlib
#RANLIB=echo RANLIB=echo
# where make install puts libpng.a and png.h # where make install puts libpng.a and png.h
prefix=/usr/local prefix=/usr/local
OBJS = png.o pngrcb.o pngrutil.o pngtrans.o pngwutil.o \ OBJS = png.o pngrcb.o pngrutil.o pngtrans.o pngwutil.o \
pngread.o pngstub.o pngwrite.o pngrtran.o pngwtran.o pngread.o pngio.o pngwrite.o pngrtran.o pngwtran.o \
pngmem.o pngerror.o
all: libpng.a pngtest all: libpng.a pngtest
@ -22,13 +23,18 @@ libpng.a: $(OBJS)
$(RANLIB) $@ $(RANLIB) $@
pngtest: pngtest.o libpng.a pngtest: pngtest.o libpng.a
cc -o pngtest $(CCFLAGS) pngtest.o $(LDFLAGS) $(CC) -o pngtest $(CCFLAGS) pngtest.o $(LDFLAGS)
test: pngtest
./pngtest
install: libpng.a install: libpng.a
-@mkdir $(prefix)/include -@mkdir $(prefix)/include
-@mkdir $(prefix)/lib -@mkdir $(prefix)/lib
cp png.h $(prefix)/include cp png.h $(prefix)/include
cp pngconf.h $(prefix)/include
chmod 644 $(prefix)/include/png.h chmod 644 $(prefix)/include/png.h
chmod 644 $(prefix)/include/pngconf.h
cp libpng.a $(prefix)/lib cp libpng.a $(prefix)/lib
chmod 644 $(prefix)/lib/libpng.a chmod 644 $(prefix)/lib/libpng.a
@ -37,13 +43,16 @@ clean:
# DO NOT DELETE THIS LINE -- make depend depends on it. # DO NOT DELETE THIS LINE -- make depend depends on it.
pngrcb.o: png.h png.o: png.h pngconf.h
pngread.o: png.h pngerror.o: png.h pngconf.h
pngrtran.o: png.h pngio.o: png.h pngconf.h
pngrutil.o: png.h pngmem.o: png.h pngconf.h
pngstub.o: png.h pngrcb.o: png.h pngconf.h
pngtest.o: png.h pngread.o: png.h pngconf.h
pngtrans.o: png.h pngrtran.o: png.h pngconf.h
pngwrite.o: png.h pngrutil.o: png.h pngconf.h
pngwtran.o: png.h pngtest.o: png.h pngconf.h
pngwutil.o: png.h pngtrans.o: png.h pngconf.h
pngwrite.o: png.h pngconf.h
pngwtran.o: png.h pngconf.h
pngwutil.o: png.h pngconf.h

61
makefile.knr
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@ -1,61 +0,0 @@
# makefile for libpng
# Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
# For conditions of distribution and use, see copyright notice in png.h
CC=cc
CFLAGS=-I../zlib -O
LDFLAGS=-L. -L../zlib/ -lpng -lgz -lm
# flags for ansi2knr
ANSI2KNRFLAGS=
RANLIB=ranlib
#RANLIB=echo
# where make install puts libpng.a and png.h
prefix=/usr/local
OBJS = png.o pngrcb.o pngrutil.o pngtrans.o pngwutil.o \
pngread.o pngstub.o pngwrite.o pngrtran.o pngwtran.o
all: ansi2knr libpng.a pngtest
# general rule to allow ansi2knr to work
.c.o:
./ansi2knr $*.c T$*.c
$(CC) $(CFLAGS) -c T$*.c
rm -f T$*.c $*.o
mv T$*.o $*.o
ansi2knr: ansi2knr.c
$(CC) $(CFLAGS) $(ANSI2KNRFLAGS) -o ansi2knr ansi2knr.c
libpng.a: ansi2knr $(OBJS)
ar rc $@ $(OBJS)
$(RANLIB) $@
pngtest: pngtest.o libpng.a ansi2knr
cc -o pngtest $(CCFLAGS) pngtest.o $(LDFLAGS)
install: libpng.a
-@mkdir $(prefix)/include
-@mkdir $(prefix)/lib
cp png.h $(prefix)/include
chmod 644 $(prefix)/include/png.h
cp libpng.a $(prefix)/lib
chmod 644 $(prefix)/lib/libpng.a
clean:
rm -f *.o libpng.a pngtest pngout.png ansi2knr
# DO NOT DELETE THIS LINE -- make depend depends on it.
pngrcb.o: png.h
pngread.o: png.h
pngrtran.o: png.h
pngrutil.o: png.h
pngstub.o: png.h
pngtest.o: png.h
pngtrans.o: png.h
pngwrite.o: png.h
pngwtran.o: png.h
pngwutil.o: png.h

50
makefile.mip
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@ -1,50 +0,0 @@
# makefile for libpng
# Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
# For conditions of distribution and use, see copyright notice in png.h
CC=cc
CFLAGS=-I../zlib -O -systype sysv -DSYSV -w -Dmips
#CFLAGS=-O
LDFLAGS=-L. -L../zlib/ -lpng -lgz -lm
#RANLIB=ranlib
RANLIB=echo
# where make install puts libpng.a and png.h
prefix=/usr/local
OBJS = png.o pngrcb.o pngrutil.o pngtrans.o pngwutil.o \
pngread.o pngstub.o pngwrite.o pngrtran.o pngwtran.o
all: libpng.a pngtest
libpng.a: $(OBJS)
ar rc $@ $(OBJS)
$(RANLIB) $@
pngtest: pngtest.o libpng.a
cc -o pngtest $(CCFLAGS) pngtest.o $(LDFLAGS)
install: libpng.a
-@mkdir $(prefix)/include
-@mkdir $(prefix)/lib
cp png.h $(prefix)/include
chmod 644 $(prefix)/include/png.h
cp libpng.a $(prefix)/lib
chmod 644 $(prefix)/lib/libpng.a
clean:
rm -f *.o libpng.a pngtest pngout.png
# DO NOT DELETE THIS LINE -- make depend depends on it.
pngrcb.o: png.h
pngread.o: png.h
pngrtran.o: png.h
pngrutil.o: png.h
pngstub.o: png.h
pngtest.o: png.h
pngtrans.o: png.h
pngwrite.o: png.h
pngwtran.o: png.h
pngwutil.o: png.h

49
makefile.std
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@ -1,49 +0,0 @@
# makefile for libpng
# Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
# For conditions of distribution and use, see copyright notice in png.h
CC=cc
CFLAGS=-I../zlib -O
LDFLAGS=-L. -L../zlib/ -lpng -lgz -lm
#RANLIB=ranlib
RANLIB=echo
# where make install puts libpng.a and png.h
prefix=/usr/local
OBJS = png.o pngrcb.o pngrutil.o pngtrans.o pngwutil.o \
pngread.o pngstub.o pngwrite.o pngrtran.o pngwtran.o
all: libpng.a pngtest
libpng.a: $(OBJS)
ar rc $@ $(OBJS)
$(RANLIB) $@
pngtest: pngtest.o libpng.a
cc -o pngtest $(CCFLAGS) pngtest.o $(LDFLAGS)
install: libpng.a
-@mkdir $(prefix)/include
-@mkdir $(prefix)/lib
cp png.h $(prefix)/include
chmod 644 $(prefix)/include/png.h
cp libpng.a $(prefix)/lib
chmod 644 $(prefix)/lib/libpng.a
clean:
rm -f *.o libpng.a pngtest pngout.png
# DO NOT DELETE THIS LINE -- make depend depends on it.
pngrcb.o: png.h
pngread.o: png.h
pngrtran.o: png.h
pngrutil.o: png.h
pngstub.o: png.h
pngtest.o: png.h
pngtrans.o: png.h
pngwrite.o: png.h
pngwtran.o: png.h
pngwutil.o: png.h

53
png.c
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@ -1,16 +1,20 @@
/* png.c - location for general purpose png functions /* png.c - location for general purpose png functions
libpng 1.0 beta 1 - version 0.71 libpng 1.0 beta 2 - version 0.81
For conditions of distribution and use, see copyright notice in png.h For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc. Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
June 26, 1995 August 24, 1995
*/ */
#define PNG_INTERNAL #define PNG_INTERNAL
#define PNG_NO_EXTERN #define PNG_NO_EXTERN
#include "png.h" #include "png.h"
/* version information for c files. This better match the version
string defined in png.h */
char png_libpng_ver[] = "0.81";
/* place to hold the signiture string for a png file. */ /* place to hold the signiture string for a png file. */
png_byte png_sig[8] = {137, 80, 78, 71, 13, 10, 26, 10}; png_byte png_sig[8] = {137, 80, 78, 71, 13, 10, 26, 10};
@ -21,17 +25,39 @@ png_byte png_IHDR[4] = { 73, 72, 68, 82};
png_byte png_IDAT[4] = { 73, 68, 65, 84}; png_byte png_IDAT[4] = { 73, 68, 65, 84};
png_byte png_IEND[4] = { 73, 69, 78, 68}; png_byte png_IEND[4] = { 73, 69, 78, 68};
png_byte png_PLTE[4] = { 80, 76, 84, 69}; png_byte png_PLTE[4] = { 80, 76, 84, 69};
#if defined(PNG_READ_gAMA_SUPPORTED) || defined(PNG_WRITE_gAMA_SUPPORTED)
png_byte png_gAMA[4] = {103, 65, 77, 65}; png_byte png_gAMA[4] = {103, 65, 77, 65};
#endif
#if defined(PNG_READ_sBIT_SUPPORTED) || defined(PNG_WRITE_sBIT_SUPPORTED)
png_byte png_sBIT[4] = {115, 66, 73, 84}; png_byte png_sBIT[4] = {115, 66, 73, 84};
#endif
#if defined(PNG_READ_cHRM_SUPPORTED) || defined(PNG_WRITE_cHRM_SUPPORTED)
png_byte png_cHRM[4] = { 99, 72, 82, 77}; png_byte png_cHRM[4] = { 99, 72, 82, 77};
#endif
#if defined(PNG_READ_tRNS_SUPPORTED) || defined(PNG_WRITE_tRNS_SUPPORTED)
png_byte png_tRNS[4] = {116, 82, 78, 83}; png_byte png_tRNS[4] = {116, 82, 78, 83};
#endif
#if defined(PNG_READ_bKGD_SUPPORTED) || defined(PNG_WRITE_bKGD_SUPPORTED)
png_byte png_bKGD[4] = { 98, 75, 71, 68}; png_byte png_bKGD[4] = { 98, 75, 71, 68};
#endif
#if defined(PNG_READ_hIST_SUPPORTED) || defined(PNG_WRITE_hIST_SUPPORTED)
png_byte png_hIST[4] = {104, 73, 83, 84}; png_byte png_hIST[4] = {104, 73, 83, 84};
#endif
#if defined(PNG_READ_tEXt_SUPPORTED) || defined(PNG_WRITE_tEXt_SUPPORTED)
png_byte png_tEXt[4] = {116, 69, 88, 116}; png_byte png_tEXt[4] = {116, 69, 88, 116};
#endif
#if defined(PNG_READ_zTXt_SUPPORTED) || defined(PNG_WRITE_zTXt_SUPPORTED)
png_byte png_zTXt[4] = {122, 84, 88, 116}; png_byte png_zTXt[4] = {122, 84, 88, 116};
#endif
#if defined(PNG_READ_pHYs_SUPPORTED) || defined(PNG_WRITE_pHYs_SUPPORTED)
png_byte png_pHYs[4] = {112, 72, 89, 115}; png_byte png_pHYs[4] = {112, 72, 89, 115};
#endif
#if defined(PNG_READ_oFFs_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED)
png_byte png_oFFs[4] = {111, 70, 70, 115}; png_byte png_oFFs[4] = {111, 70, 70, 115};
#endif
#if defined(PNG_READ_tIME_SUPPORTED) || defined(PNG_WRITE_tIME_SUPPORTED)
png_byte png_tIME[4] = {116, 73, 77, 69}; png_byte png_tIME[4] = {116, 73, 77, 69};
#endif
/* arrays to facilitate easy interlacing - use pass (0 - 6) as index */ /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
@ -78,18 +104,18 @@ png_check_sig(png_byte *sig, int num)
} }
/* Function to allocate memory for zlib. */ /* Function to allocate memory for zlib. */
voidp voidpf
png_zalloc(voidp png_ptr, uInt items, uInt size) png_zalloc(voidpf png_ptr, uInt items, uInt size)
{ {
return ((voidp)png_large_malloc((png_struct *)png_ptr, return ((voidpf)png_large_malloc((png_struct FAR *)png_ptr,
(png_uint_32)items * (png_uint_32)size)); (png_uint_32)items * (png_uint_32)size));
} }
/* function to free memory for zlib */ /* function to free memory for zlib */
void void
png_zfree(voidp png_ptr, voidp ptr) png_zfree(voidpf png_ptr, voidpf ptr)
{ {
png_large_free((png_struct *)png_ptr, (void *)ptr); png_large_free((png_struct FAR *)png_ptr, (voidpf)ptr);
} }
/* reset the crc variable to 32 bits of 1's. Care must be taken /* reset the crc variable to 32 bits of 1's. Care must be taken
@ -135,10 +161,10 @@ make_crc_table(void)
initialized to all 1's, and the transmitted value is the 1's complement initialized to all 1's, and the transmitted value is the 1's complement
of the final running crc. */ of the final running crc. */
static png_uint_32 static png_uint_32
update_crc(png_uint_32 crc, png_byte *buf, png_uint_32 len) update_crc(png_uint_32 crc, png_bytef *buf, png_uint_32 len)
{ {
png_uint_32 c; png_uint_32 c;
png_byte *p; png_bytef *p;
png_uint_32 n; png_uint_32 n;
c = crc; c = crc;
@ -163,10 +189,15 @@ update_crc(png_uint_32 crc, png_byte *buf, png_uint_32 len)
would need to use huge pointers to access all that data. If you would need to use huge pointers to access all that data. If you
need this, put huge here and above. */ need this, put huge here and above. */
void void
png_calculate_crc(png_struct *png_ptr, png_byte *ptr, png_calculate_crc(png_struct *png_ptr, png_bytef *ptr,
png_uint_32 length) png_uint_32 length)
{ {
png_ptr->crc = update_crc(png_ptr->crc, ptr, length); png_ptr->crc = update_crc(png_ptr->crc, ptr, length);
} }
void
png_info_init(png_info *info)
{
/* set everything to 0 */
memset(info, 0, sizeof (png_info));
}

600
png.h
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File diff suppressed because it is too large Load Diff

16
pngchang.txt
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@ -40,5 +40,21 @@ version 0.7
version 0.71 version 0.71
changed pngtest.png for zlib 0.93 changed pngtest.png for zlib 0.93
fixed error in libpng.txt and example.c fixed error in libpng.txt and example.c
version 0.8
cleaned up some bugs
added png_set_filler()
split up pngstub.c into pngmem.c, pngio.c, and pngerror.c
added #define's to remove unwanted code
moved png_info_init() to png.c
added old_size into png_realloc()
added functions to manually set filtering and compression info
changed compression parameters based on image type
optimized filter selection code
added version info
changed external functions passing floats to doubles (k&r problems?)
put all the configurable stuff in pngconf.h
enabled png_set_shift to work with paletted images on read
added png_read_update_info() - updates info structure with transformations

256
pngconf.h Normal file
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@ -0,0 +1,256 @@
/* pngconf.c - machine configurable file for libpng
libpng 1.0 beta 2 - version 0.81
For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
August 24, 1995
*/
/* Any machine specific code is near the front of this file, so if you
are configuring libpng for a machine, you may want to read the section
starting here down to where it starts to typedef png_color, png_text,
and png_info */
#ifndef PNGCONF_H
#define PNGCONF_H
/* this is the size of the compression buffer, and thus the size of
an IDAT chunk. Make this whatever size you feel is best for your
machine. One of these will be allocated per png_struct. When this
is full, it writes the data to the disk, and does some other
calculations. Making this an extreamly small size will slow
the library down, but you may want to experiment to determine
where it becomes significant, if you are concerned with memory
usage. Note that zlib allocates at least 32Kb also. For readers,
this describes the size of the buffer available to read the data in.
Unless this gets smaller then the size of a row (compressed),
it should not make much difference how big this is. */
#define PNG_ZBUF_SIZE 8192
/* While libpng currently uses zlib for it's compression, it has been designed
to stand on it's own. Towards this end, there are two defines that are
used to help portability between machines. To make it simpler to
setup libpng on a machine, this currently uses zlib's definitions, so
any changes should be made in zlib. Libpng will check zlib's settings
and adjust it's own accordingly. */
/* if you are running on a machine where you cannot allocate more then
64K of memory, uncomment this. While libpng will not normally need
that much memory in a chunk (unless you load up a very large file),
zlib needs to know how big of a chunk it can use, and libpng thus
makes sure to check any memory allocation to verify it will fit
into memory.
#define PNG_MAX_ALLOC_64K
*/
#ifdef MAXSEG_64K
#define PNG_MAX_ALLOC_64K
#endif
/* this macro protects us against machines that don't have function
prototypes. If your compiler does not handle function prototypes,
define this macro. I've always been able to use _NO_PROTO as the
indicator, but you may need to drag the empty declaration out in
front of here, or change the ifdef to suit your own needs. */
#ifndef PNGARG
#ifdef OF
#define PNGARG(arglist) OF(arglist)
#else
#ifdef _NO_PROTO
#define PNGARG(arglist)
#else
#define PNGARG(arglist) arglist
#endif /* _NO_PROTO */
#endif /* OF */
#endif /* PNGARG */
/* enough people need this for various reasons to include it here */
#ifndef MACOS
#include <sys/types.h>
#endif
/* need the time information for reading tIME chunks */
#include <time.h>
/* for FILE. If you are not using standard io, you don't need this */
#include <stdio.h>
/* include setjmp.h for error handling */
#include <setjmp.h>
#ifdef BSD
#include <strings.h>
#else
#include <string.h>
#endif
/* other defines for things like memory and the like can go here. These
are the only files included in libpng, so if you need to change them,
change them here. They are only included if PNG_INTERNAL is defined. */
#ifdef PNG_INTERNAL
#include <stdlib.h>
#include <ctype.h>
#include <math.h>
/* other defines specific to compilers can go here. Try to keep
them inside an appropriate ifdef/endif pair for portability */
/* for some reason, Borland C++ defines memcmp, etc. in mem.h, not
stdlib.h like it should (I think). Or perhaps this is a C++
feature */
#ifdef __TURBOC__
#include <mem.h>
#include "alloc.h"
#endif
#ifdef _MSC_VER
#include <malloc.h>
#endif
/* this controls how fine the dithering gets. As this allocates
a largish chunk of memory (32K), those who are not as concerned
with dithering quality can decrease some or all of these */
#define PNG_DITHER_RED_BITS 5
#define PNG_DITHER_GREEN_BITS 5
#define PNG_DITHER_BLUE_BITS 5
/* this controls how fine the gamma correction becomes when you
are only interested in 8 bits anyway. Increasing this value
results in more memory being used, and more pow() functions
being called to fill in the gamma tables. Don't get this
value less then 8, and even that may not work (I haven't tested
it). */
#define PNG_MAX_GAMMA_8 11
#endif /* PNG_INTERNAL */
/* The following defines give you the ability to remove code
from the library that you will not be using. I wish I
could figure out how to automate this, but I can't do
that without making it seriously hard on the users. So
if you are not using an ability, change the #define to
and #undef, and that part of the library will not be
compiled. If your linker can't find a function, you
may want to make sure the ability is defined here.
Some of these depend upon some others being defined.
I haven't figured out all the interactions here, so
you may have to experiment awhile to get everything
to compile.
*/
/* Any transformations you will not be using can be undef'ed here */
#define PNG_READ_INTERLACING_SUPPORTED
#define PNG_READ_EXPAND_SUPPORTED
#define PNG_READ_SHIFT_SUPPORTED
#define PNG_READ_PACK_SUPPORTED
#define PNG_READ_BGR_SUPPORTED
#define PNG_READ_SWAP_SUPPORTED
#define PNG_READ_INVERT_SUPPORTED
#define PNG_READ_DITHER_SUPPORTED
#define PNG_READ_BACKGROUND_SUPPORTED
#define PNG_READ_16_TO_8_SUPPORTED
#define PNG_READ_FILLER_SUPPORTED
#define PNG_READ_GAMMA_SUPPORTED
#define PNG_READ_GRAY_TO_RGB_SUPPORTED
#define PNG_WRITE_INTERLACING_SUPPORTED
#define PNG_WRITE_SHIFT_SUPPORTED
#define PNG_WRITE_PACK_SUPPORTED
#define PNG_WRITE_BGR_SUPPORTED
#define PNG_WRITE_SWAP_SUPPORTED
#define PNG_WRITE_INVERT_SUPPORTED
#define PNG_WRITE_FILLER_SUPPORTED
/* any chunks you are not interested in, you can undef here. The
ones that allocate memory may be expecially important (hIST,
tEXt, zTXt, tRNS) Others will just save time and make png_info
smaller. OPT_PLTE only disables the optional palette in RGB
and RGB Alpha images. */
#define PNG_READ_gAMA_SUPPORTED
#define PNG_READ_sBIT_SUPPORTED
#define PNG_READ_cHRM_SUPPORTED
#define PNG_READ_tRNS_SUPPORTED
#define PNG_READ_bKGD_SUPPORTED
#define PNG_READ_hIST_SUPPORTED
#define PNG_READ_pHYs_SUPPORTED
#define PNG_READ_oFFs_SUPPORTED
#define PNG_READ_tIME_SUPPORTED
#define PNG_READ_tEXt_SUPPORTED
#define PNG_READ_zTXt_SUPPORTED
#define PNG_READ_OPT_PLTE_SUPPORTED
#define PNG_WRITE_gAMA_SUPPORTED
#define PNG_WRITE_sBIT_SUPPORTED
#define PNG_WRITE_cHRM_SUPPORTED
#define PNG_WRITE_tRNS_SUPPORTED
#define PNG_WRITE_bKGD_SUPPORTED
#define PNG_WRITE_hIST_SUPPORTED
#define PNG_WRITE_pHYs_SUPPORTED
#define PNG_WRITE_oFFs_SUPPORTED
#define PNG_WRITE_tIME_SUPPORTED
#define PNG_WRITE_tEXt_SUPPORTED
#define PNG_WRITE_zTXt_SUPPORTED
/* some typedefs to get us started. These should be safe on most of the
common platforms. The typedefs should be at least as large
as the numbers suggest (a png_uint_32 must be at least 32 bits long),
but they don't have to be exactly that size. */
typedef unsigned long png_uint_32;
typedef long png_int_32;
typedef unsigned short png_uint_16;
typedef short png_int_16;
typedef unsigned char png_byte;
/* this is usually size_t. it is typedef'ed just in case you need it to
change (I'm not sure if you will or not, so I thought I'd be safe) */
typedef size_t png_size_t;
/* The following is needed for medium model support. It cannot be in the
PNG_INTERNAL section. Needs modification for other compilers besides
MSC. Model independent support declares all arrays that might be very
large using the far keyword. The Zlib version used must also support
model independent data. As of version Zlib .95, the necessary changes
have been made in Zlib. The USE_FAR_KEYWORD define triggers other
changes that are needed. Most of the far keyword changes are hidden
inside typedefs with suffix "f". Tim Wegner */
#if defined(FAR) && defined(M_I86MM) /* MSC Medium model */
# define USE_FAR_KEYWORD
#else
# define FAR
#endif
typedef unsigned char FAR png_bytef;
/* End medium model changes to be in zconf.h */
/* User may want to use these so not in PNG_INTERNAL. Any library functions
that are passed far data must be model independent. */
#if defined(USE_FAR_KEYWORD) /* memory model independent fns */
# define png_strcpy _fstrcpy
# define png_strcat _fstrcat
# define png_strlen _fstrlen
# define png_strcmp _fstrcmp
# define png_memcpy _fmemcpy
# define png_memset _fmemset
#else /* use the usual functions */
# define png_strcpy strcpy
# define png_strcat strcat
# define png_strlen strlen
# define png_strcmp strcmp
# define png_memcpy memcpy
# define png_memset memset
#endif
/* End of memory model independent support */
#endif /* PNGCONF_H */

46
pngerror.c Normal file
View File

@ -0,0 +1,46 @@
/* pngstub.c - stub functions for i/o and memory allocation
libpng 1.0 beta 2 - version 0.81
For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
August 24, 1995
This file provides a location for all error handling. Users which
need special error handling are expected to modify the code in this
file to meet their needs. See the instructions at each function. */
#define PNG_INTERNAL
#include "png.h"
/* This function is called whenever there is an error. Replace with
however you wish to handle the error. Note that this function
MUST NOT return, or the program will crash */
void
png_error(png_structf *png_ptr, char *message)
{
fprintf(stderr, "libpng error: %s\n", message);
#ifdef USE_FAR_KEYWORD
{
jmp_buf jmpbuf;
png_memcpy(jmpbuf,png_ptr->jmpbuf,sizeof(jmp_buf));
longjmp(jmpbuf, 1);
}
#else
longjmp(png_ptr->jmpbuf, 1);
#endif
}
/* This function is called when there is a warning, but the library
thinks it can continue anyway. You don't have to do anything here
if you don't want to. In the default configuration, png_ptr is
not used, but it is passed in case it may be useful. */
void
png_warning(png_struct *png_ptr, char *message)
{
if (!png_ptr)
return;
fprintf(stderr, "libpng warning: %s\n", message);
}

180
pngio.c Normal file
View File

@ -0,0 +1,180 @@
/* pngstub.c - stub functions for i/o and memory allocation
libpng 1.0 beta 2 - version 0.81
For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
August 24, 1995
This file provides a location for all input/output. Users which need
special handling are expected to modify the code in this file to meet
their needs. See the instructions at each function. */
#define PNG_INTERNAL
#include "png.h"
/* Write the data to whatever output you are using. The default
routine writes to a file pointer. If you need to write to something
else, this is the place to do it. We suggest saving the old code
for future use, possibly in a #define. Note that this routine sometimes
gets called with very small lengths, so you should implement some kind
of simple buffering if you are using unbuffered writes. This should
never be asked to write more then 64K on a 16 bit machine. The cast
to png_size_t is there for insurance, but if you are having problems
with it, you can take it out. Just be sure to cast length to whatever
fwrite needs in that spot if you don't have a function prototype for
it. */
#ifndef USE_FAR_KEYWORD
void
png_write_data(png_struct *png_ptr, png_bytef *data, png_uint_32 length)
{
png_uint_32 check;
check = fwrite(data, 1, (png_size_t)length, png_ptr->fp);
if (check != length)
{
png_error(png_ptr, "Write Error");
}
}
#else
/* this is the model-independent version. Since the standard I/O library
can't handle far buffers in the medium and small models, we have to copy
the data.
*/
#define NEAR_BUF_SIZE 1024
#define MIN(a,b) (a <= b ? a : b)
#ifdef _MSC_VER
/* for FP_OFF */
#include <dos.h>
#endif
void
png_write_data(png_struct *png_ptr, png_bytef *data, png_uint_32 length)
{
png_uint_32 check;
png_byte *n_data;
/* Check if data really is near. If so, use usual code. */
#ifdef _MSC_VER
/* do it this way just to quiet warning */
FP_OFF(n_data) = FP_OFF(data);
if(FP_SEG(n_data) == FP_SEG(data))
#else
/* this works in MSC also but with lost segment warning */
n_data = (png_byte *)data;
if((png_bytef *)n_data == data)
#endif
{
check = fwrite(n_data, 1, (png_size_t)length, png_ptr->fp);
}
else
{
png_byte buf[NEAR_BUF_SIZE];
png_size_t written, remaining, err;
check = 0;
remaining = (png_size_t)length;
do
{
written = MIN(NEAR_BUF_SIZE,remaining);
png_memcpy(buf,data,written); /* copy far buffer to near buffer */
err = fwrite(buf, 1, written, png_ptr->fp);
if(err != written)
break;
else
check += err;
data += written;
remaining -= written;
}
while(remaining != 0);
}
if (check != length)
{
png_error(png_ptr, "Write Error");
}
}
#endif
/* Read the data from whatever input you are using. The default
routine reads from a file pointer. If you need to read from something
else, this is the place to do it. We suggest saving the old code
for future use. Note that this routine sometimes gets called with
very small lengths, so you should implement some kind of simple
buffering if you are using unbuffered reads. This should
never be asked to read more then 64K on a 16 bit machine. The cast
to png_size_t is there for insurance, but if you are having problems
with it, you can take it out. Just be sure to cast length to whatever
fread needs in that spot if you don't have a function prototype for
it. */
#ifndef USE_FAR_KEYWORD
void
png_read_data(png_struct *png_ptr, png_bytef *data, png_uint_32 length)
{
png_uint_32 check;
check = fread(data, 1, (size_t)length, png_ptr->fp);
if (check != length)
{
png_error(png_ptr, "Read Error");
}
}
#else
void
png_read_data(png_struct *png_ptr, png_bytef *data, png_uint_32 length)
{
png_uint_32 check;
png_byte *n_data;
/* Check if data really is near. If so, use usual code. */
#ifdef _MSC_VER
/* do it this way just to quiet warning */
FP_OFF(n_data) = FP_OFF(data);
if(FP_SEG(n_data) == FP_SEG(data))
#else
/* this works in MSC also but with lost segment warning */
n_data = (png_byte *)data;
if((png_bytef *)n_data == data)
#endif
{
check = fread(n_data, 1, (size_t)length, png_ptr->fp);
}
else
{
png_byte buf[NEAR_BUF_SIZE];
png_size_t read, remaining, err;
check = 0;
remaining = (png_size_t)length;
do
{
read = MIN(NEAR_BUF_SIZE,remaining);
err = fread(buf, 1, read, png_ptr->fp);
png_memcpy(data,buf,read); /* copy far buffer to near buffer */
if(err != read)
break;
else
check += err;
data += read;
remaining -= read;
}
while(remaining != 0);
}
if (check != length)
{
png_error(png_ptr, "read Error");
}
}
#endif
/* Initialize the input/output for the png file. If you change
the read and write routines, you will probably need to change
this routine (or write your own). If you change the parameters
of this routine, remember to change png.h also. */
void
png_init_io(png_struct *png_ptr, FILE *fp)
{
png_ptr->fp = fp;
}

142
pngstub.c → pngmem.c
View File

@ -1,75 +1,18 @@
/* pngstub.c - stub functions for i/o and memory allocation /* pngstub.c - stub functions for i/o and memory allocation
libpng 1.0 beta 1 - version 0.71 libpng 1.0 beta 2 - version 0.81
For conditions of distribution and use, see copyright notice in png.h For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc. Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
June 26, 1995 August 24, 1995
This file provides a location for all input/output, memory location, This file provides a location for all memory allocation. Users which
and error handling. Users which need special handling in these areas need special memory handling are expected to modify the code in this file
are expected to modify the code in this file to meet their needs. See to meet their needs. See the instructions at each function. */
the instructions at each function. */
#define PNG_INTERNAL #define PNG_INTERNAL
#include "png.h" #include "png.h"
/* Write the data to whatever output you are using. The default
routine writes to a file pointer. If you need to write to something
else, this is the place to do it. We suggest saving the old code
for future use, possibly in a #define. Note that this routine sometimes
gets called with very small lengths, so you should implement some kind
of simple buffering if you are using unbuffered writes. This should
never be asked to write more then 64K on a 16 bit machine. The cast
to png_size_t is there for insurance, but if you are having problems
with it, you can take it out. Just be sure to cast length to whatever
fwrite needs in that spot if you don't have a function prototype for
it. */
void
png_write_data(png_struct *png_ptr, png_byte *data, png_uint_32 length)
{
png_uint_32 check;
check = fwrite(data, 1, (png_size_t)length, png_ptr->fp);
if (check != length)
{
png_error(png_ptr, "Write Error");
}
}
/* Read the data from whatever input you are using. The default
routine reads from a file pointer. If you need to read from something
else, this is the place to do it. We suggest saving the old code
for future use. Note that this routine sometimes gets called with
very small lengths, so you should implement some kind of simple
buffering if you are using unbuffered reads. This should
never be asked to read more then 64K on a 16 bit machine. The cast
to png_size_t is there for insurance, but if you are having problems
with it, you can take it out. Just be sure to cast length to whatever
fread needs in that spot if you don't have a function prototype for
it. */
void
png_read_data(png_struct *png_ptr, png_byte *data, png_uint_32 length)
{
png_uint_32 check;
check = fread(data, 1, (size_t)length, png_ptr->fp);
if (check != length)
{
png_error(png_ptr, "Read Error");
}
}
/* Initialize the input/output for the png file. If you change
the read and write routines, you will probably need to change
this routine (or write your own). If you change the parameters
of this routine, remember to change png.h also. */
void
png_init_io(png_struct *png_ptr, FILE *fp)
{
png_ptr->fp = fp;
}
/* Allocate memory. For reasonable files, size should never exceed /* Allocate memory. For reasonable files, size should never exceed
64K. However, zlib may allocate more then 64K if you don't tell 64K. However, zlib may allocate more then 64K if you don't tell
it not to. See zconf.h and png.h for more information. zlib does it not to. See zconf.h and png.h for more information. zlib does
@ -89,6 +32,7 @@ png_init_io(png_struct *png_ptr, FILE *fp)
*/ */
#ifdef __TURBOC__ #ifdef __TURBOC__
#ifndef __WIN32__ #ifndef __WIN32__
#ifndef __FLAT__
/* NUM_SEG is the number of segments allocated at once */ /* NUM_SEG is the number of segments allocated at once */
#define NUM_SEG 4 #define NUM_SEG 4
@ -104,13 +48,16 @@ borland_seg *save_array;
int num_save_array; int num_save_array;
int max_save_array; int max_save_array;
#endif
#endif #endif
#endif #endif
void * voidpf
png_large_malloc(png_struct *png_ptr, png_uint_32 size) png_large_malloc(png_structf *png_ptr, png_uint_32 size)
{ {
void *ret; voidpf ret;
if (!png_ptr || !size)
return ((void *)0);
#ifdef PNG_MAX_MALLOC_64K #ifdef PNG_MAX_MALLOC_64K
if (size > (png_uint_32)65536L) if (size > (png_uint_32)65536L)
@ -118,8 +65,8 @@ png_large_malloc(png_struct *png_ptr, png_uint_32 size)
#endif #endif
#ifdef __TURBOC__ #ifdef __TURBOC__
# ifdef __WIN32__ # if defined(__WIN32__) || defined(__FLAT__)
ret = farmalloc(size); ret = malloc(size);
# else # else
if (size == 65536L) if (size == 65536L)
@ -152,11 +99,11 @@ png_large_malloc(png_struct *png_ptr, png_uint_32 size)
num_save_array = 1; num_save_array = 1;
save_array = malloc(num_save_array * sizeof (borland_seg)); save_array = malloc(num_save_array * sizeof (borland_seg));
if (!save_array) if (!save_array)
png_error(png_ptr, "Out of Memory"); png_error(png_ptr, "Out of Memory 1");
save_array->mem_ptr = farmalloc( save_array->mem_ptr = farmalloc(
(unsigned long)(NUM_SEG) * 65536L + 65528L); (unsigned long)(NUM_SEG) * 65536L + 65532L);
if (!save_array->mem_ptr) if (!save_array->mem_ptr)
png_error(png_ptr, "Out of Memory"); png_error(png_ptr, "Out of Memory 2");
offset = (unsigned long)(ret); offset = (unsigned long)(ret);
offset &= 0xffffL; offset &= 0xffffL;
ptr = save_array->mem_ptr; ptr = save_array->mem_ptr;
@ -194,11 +141,11 @@ png_large_malloc(png_struct *png_ptr, png_uint_32 size)
save_array = realloc(save_array, save_array = realloc(save_array,
(num_save_array + 1) * sizeof (borland_seg)); (num_save_array + 1) * sizeof (borland_seg));
if (!save_array) if (!save_array)
png_error(png_ptr, "Out of Memory"); png_error(png_ptr, "Out of Memory 3");
save_array[num_save_array].mem_ptr = farmalloc( save_array[num_save_array].mem_ptr = farmalloc(
(unsigned long)(NUM_SEG) * 65536L + 65528L); (unsigned long)(NUM_SEG) * 65536L + 65532L);
if (!save_array[num_save_array].mem_ptr) if (!save_array[num_save_array].mem_ptr)
png_error(png_ptr, "Out of Memory"); png_error(png_ptr, "Out of Memory 4");
offset = (unsigned long)(ret); offset = (unsigned long)(ret);
offset &= 0xffffL; offset &= 0xffffL;
ptr = save_array[num_save_array].mem_ptr; ptr = save_array[num_save_array].mem_ptr;
@ -231,7 +178,7 @@ png_large_malloc(png_struct *png_ptr, png_uint_32 size)
# endif # endif
#endif #endif
if (!ret) if (ret == NULL)
{ {
png_error(png_ptr, "Out of Memory"); png_error(png_ptr, "Out of Memory");
} }
@ -243,7 +190,7 @@ png_large_malloc(png_struct *png_ptr, png_uint_32 size)
configuration, png_ptr is not used, but is passed in case it configuration, png_ptr is not used, but is passed in case it
is needed. If ptr is NULL, return without taking any action. */ is needed. If ptr is NULL, return without taking any action. */
void void
png_large_free(png_struct *png_ptr, void *ptr) png_large_free(png_structf *png_ptr, voidpf ptr)
{ {
if (!png_ptr) if (!png_ptr)
return; return;
@ -251,7 +198,10 @@ png_large_free(png_struct *png_ptr, void *ptr)
if (ptr != (void *)0) if (ptr != (void *)0)
{ {
#ifdef __TURBOC__ #ifdef __TURBOC__
# ifndef __WIN32__ # if defined(__WIN32__) || defined(__FLAT__)
if (ptr)
free(ptr);
# else
int i, j; int i, j;
for (i = 0; i < num_save_array; i++) for (i = 0; i < num_save_array; i++)
@ -260,14 +210,13 @@ png_large_free(png_struct *png_ptr, void *ptr)
{ {
if (ptr == save_array[i].seg_ptr[j]) if (ptr == save_array[i].seg_ptr[j])
{ {
printf("freeing pointer: i, j: %d, %d\n", i, j);
save_array[i].seg_used[j] = 0; save_array[i].seg_used[j] = 0;
ptr = 0; ptr = 0;
save_array[i].num_used--; save_array[i].num_used--;
if (!save_array[i].num_used) if (!save_array[i].num_used)
{ {
int k; int k;
printf("freeing array: %d\n", i);
num_save_array--; num_save_array--;
farfree(save_array[i].mem_ptr); farfree(save_array[i].mem_ptr);
for (k = i; k < num_save_array; k++) for (k = i; k < num_save_array; k++)
@ -285,9 +234,9 @@ printf("freeing array: %d\n", i);
break; break;
} }
# endif
if (ptr) if (ptr)
farfree(ptr); farfree(ptr);
# endif
#else #else
# ifdef _MSC_VER # ifdef _MSC_VER
hfree(ptr); hfree(ptr);
@ -305,7 +254,7 @@ png_malloc(png_struct *png_ptr, png_uint_32 size)
{ {
void *ret; void *ret;
if (!png_ptr) if (!png_ptr || !size)
return ((void *)0); return ((void *)0);
#ifdef PNG_MAX_MALLOC_64K #ifdef PNG_MAX_MALLOC_64K
@ -317,7 +266,7 @@ png_malloc(png_struct *png_ptr, png_uint_32 size)
if (!ret) if (!ret)
{ {
png_error(png_ptr, "Out of Memory"); png_error(png_ptr, "Out of Memory 6");
} }
return ret; return ret;
@ -326,11 +275,12 @@ png_malloc(png_struct *png_ptr, png_uint_32 size)
/* Reallocate memory. This will not get near 64K on a /* Reallocate memory. This will not get near 64K on a
even marginally reasonable file. */ even marginally reasonable file. */
void * void *
png_realloc(png_struct *png_ptr, void *ptr, png_uint_32 size) png_realloc(png_struct *png_ptr, void *ptr, png_uint_32 size,
png_uint_32 old_size)
{ {
void *ret; void *ret;
if (!png_ptr) if (!png_ptr || !old_size || !ptr || !size)
return ((void *)0); return ((void *)0);
#ifdef PNG_MAX_MALLOC_64K #ifdef PNG_MAX_MALLOC_64K
@ -342,7 +292,7 @@ png_realloc(png_struct *png_ptr, void *ptr, png_uint_32 size)
if (!ret) if (!ret)
{ {
png_error(png_ptr, "Out of Memory"); png_error(png_ptr, "Out of Memory 7");
} }
return ret; return ret;
@ -361,27 +311,3 @@ png_free(png_struct *png_ptr, void *ptr)
free(ptr); free(ptr);
} }
/* This function is called whenever there is an error. Replace with
however you wish to handle the error. Note that this function
MUST NOT return, or the program will crash */
void
png_error(png_struct *png_ptr, char *message)
{
fprintf(stderr, "libpng error: %s\n", message);
longjmp(png_ptr->jmpbuf, 1);
}
/* This function is called when there is a warning, but the library
thinks it can continue anyway. You don't have to do anything here
if you don't want to. In the default configuration, png_ptr is
not used, but it is passed in case it may be useful. */
void
png_warning(png_struct *png_ptr, char *message)
{
if (!png_ptr)
return;
fprintf(stderr, "libpng warning: %s\n", message);
}

37
pngrcb.c
View File

@ -1,9 +1,9 @@
/* pngrcb.c - callbacks while reading a png file /* pngrcb.c - callbacks while reading a png file
libpng 1.0 beta 1 - version 0.71 libpng 1.0 beta 2 - version 0.81
For conditions of distribution and use, see copyright notice in png.h For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc. Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
June 26, 1995 August 24, 1995
*/ */
#define PNG_INTERNAL #define PNG_INTERNAL
@ -49,6 +49,7 @@ png_read_PLTE(png_struct *png_ptr, png_info *info,
info->valid |= PNG_INFO_PLTE; info->valid |= PNG_INFO_PLTE;
} }
#if defined(PNG_READ_gAMA_SUPPORTED)
void void
png_read_gAMA(png_struct *png_ptr, png_info *info, float gamma) png_read_gAMA(png_struct *png_ptr, png_info *info, float gamma)
{ {
@ -58,7 +59,9 @@ png_read_gAMA(png_struct *png_ptr, png_info *info, float gamma)
info->gamma = gamma; info->gamma = gamma;
info->valid |= PNG_INFO_gAMA; info->valid |= PNG_INFO_gAMA;
} }
#endif
#if defined(PNG_READ_sBIT_SUPPORTED)
void void
png_read_sBIT(png_struct *png_ptr, png_info *info, png_read_sBIT(png_struct *png_ptr, png_info *info,
png_color_8 *sig_bit) png_color_8 *sig_bit)
@ -69,7 +72,9 @@ png_read_sBIT(png_struct *png_ptr, png_info *info,
memcpy(&(info->sig_bit), sig_bit, sizeof (png_color_8)); memcpy(&(info->sig_bit), sig_bit, sizeof (png_color_8));
info->valid |= PNG_INFO_sBIT; info->valid |= PNG_INFO_sBIT;
} }
#endif
#if defined(PNG_READ_cHRM_SUPPORTED)
void void
png_read_cHRM(png_struct *png_ptr, png_info *info, png_read_cHRM(png_struct *png_ptr, png_info *info,
float white_x, float white_y, float red_x, float red_y, float white_x, float white_y, float red_x, float red_y,
@ -88,7 +93,9 @@ png_read_cHRM(png_struct *png_ptr, png_info *info,
info->y_blue = blue_y; info->y_blue = blue_y;
info->valid |= PNG_INFO_cHRM; info->valid |= PNG_INFO_cHRM;
} }
#endif
#if defined(PNG_READ_tRNS_SUPPORTED)
void void
png_read_tRNS(png_struct *png_ptr, png_info *info, png_read_tRNS(png_struct *png_ptr, png_info *info,
png_byte *trans, int num_trans, png_color_16 *trans_values) png_byte *trans, int num_trans, png_color_16 *trans_values)
@ -108,7 +115,9 @@ png_read_tRNS(png_struct *png_ptr, png_info *info,
info->num_trans = num_trans; info->num_trans = num_trans;
info->valid |= PNG_INFO_tRNS; info->valid |= PNG_INFO_tRNS;
} }
#endif
#if defined(PNG_READ_bKGD_SUPPORTED)
void void
png_read_bKGD(png_struct *png_ptr, png_info *info, png_read_bKGD(png_struct *png_ptr, png_info *info,
png_color_16 *background) png_color_16 *background)
@ -119,7 +128,9 @@ png_read_bKGD(png_struct *png_ptr, png_info *info,
memcpy(&(info->background), background, sizeof(png_color_16)); memcpy(&(info->background), background, sizeof(png_color_16));
info->valid |= PNG_INFO_bKGD; info->valid |= PNG_INFO_bKGD;
} }
#endif
#if defined(PNG_READ_hIST_SUPPORTED)
void void
png_read_hIST(png_struct *png_ptr, png_info *info, png_uint_16 *hist) png_read_hIST(png_struct *png_ptr, png_info *info, png_uint_16 *hist)
{ {
@ -129,7 +140,9 @@ png_read_hIST(png_struct *png_ptr, png_info *info, png_uint_16 *hist)
info->hist = hist; info->hist = hist;
info->valid |= PNG_INFO_hIST; info->valid |= PNG_INFO_hIST;
} }
#endif
#if defined(PNG_READ_pHYs_SUPPORTED)
void void
png_read_pHYs(png_struct *png_ptr, png_info *info, png_read_pHYs(png_struct *png_ptr, png_info *info,
png_uint_32 res_x, png_uint_32 res_y, int unit_type) png_uint_32 res_x, png_uint_32 res_y, int unit_type)
@ -142,7 +155,9 @@ png_read_pHYs(png_struct *png_ptr, png_info *info,
info->phys_unit_type = unit_type; info->phys_unit_type = unit_type;
info->valid |= PNG_INFO_pHYs; info->valid |= PNG_INFO_pHYs;
} }
#endif
#if defined(PNG_READ_oFFs_SUPPORTED)
void void
png_read_oFFs(png_struct *png_ptr, png_info *info, png_read_oFFs(png_struct *png_ptr, png_info *info,
png_uint_32 offset_x, png_uint_32 offset_y, int unit_type) png_uint_32 offset_x, png_uint_32 offset_y, int unit_type)
@ -155,7 +170,9 @@ png_read_oFFs(png_struct *png_ptr, png_info *info,
info->offset_unit_type = unit_type; info->offset_unit_type = unit_type;
info->valid |= PNG_INFO_oFFs; info->valid |= PNG_INFO_oFFs;
} }
#endif
#if defined(PNG_READ_tIME_SUPPORTED)
void void
png_read_tIME(png_struct *png_ptr, png_info *info, png_read_tIME(png_struct *png_ptr, png_info *info,
png_time *mod_time) png_time *mod_time)
@ -166,10 +183,12 @@ png_read_tIME(png_struct *png_ptr, png_info *info,
memcpy(&(info->mod_time), mod_time, sizeof (png_time)); memcpy(&(info->mod_time), mod_time, sizeof (png_time));
info->valid |= PNG_INFO_tIME; info->valid |= PNG_INFO_tIME;
} }
#endif
#if defined(PNG_READ_zTXt_SUPPORTED)
void void
png_read_zTXt(png_struct *png_ptr, png_info *info, png_read_zTXt(png_struct *png_ptr, png_info *info,
char *key, char *text, png_uint_32 text_len, int compression) charf *key, charf *text, png_uint_32 text_len, int compression)
{ {
if (!png_ptr || !info) if (!png_ptr || !info)
return; return;
@ -178,10 +197,14 @@ png_read_zTXt(png_struct *png_ptr, png_info *info,
{ {
if (info->text) if (info->text)
{ {
png_uint_32 old_max;
old_max = info->max_text;
info->max_text = info->num_text + 16; info->max_text = info->num_text + 16;
info->text = (png_text *)png_realloc(png_ptr, info->text = (png_text *)png_realloc(png_ptr,
info->text, info->text,
info->max_text * sizeof (png_text)); info->max_text * sizeof (png_text),
old_max * sizeof (png_text));
} }
else else
{ {
@ -198,15 +221,17 @@ png_read_zTXt(png_struct *png_ptr, png_info *info,
info->text[info->num_text].compression = compression; info->text[info->num_text].compression = compression;
info->num_text++; info->num_text++;
} }
#endif
#if defined(PNG_READ_tEXt_SUPPORTED)
void void
png_read_tEXt(png_struct *png_ptr, png_info *info, png_read_tEXt(png_struct *png_ptr, png_info *info,
char *key, char *text, png_uint_32 text_len) charf *key, charf *text, png_uint_32 text_len)
{ {
if (!png_ptr || !info) if (!png_ptr || !info)
return; return;
png_read_zTXt(png_ptr, info, key, text, text_len, -1); png_read_zTXt(png_ptr, info, key, text, text_len, -1);
} }
#endif

135
pngread.c
View File

@ -1,10 +1,10 @@
/* pngread.c - read a png file /* pngread.c - read a png file
libpng 1.0 beta 1 - version 0.71 libpng 1.0 beta 2 - version 0.81
For conditions of distribution and use, see copyright notice in png.h For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc. Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
June 26, 1995 August 24, 1995
*/ */
#define PNG_INTERNAL #define PNG_INTERNAL
@ -16,9 +16,9 @@ png_read_init(png_struct *png_ptr)
{ {
jmp_buf tmp_jmp; jmp_buf tmp_jmp;
memcpy(tmp_jmp, png_ptr->jmpbuf, sizeof (jmp_buf)); png_memcpy(tmp_jmp, png_ptr->jmpbuf, sizeof (jmp_buf));
memset(png_ptr, 0, sizeof (png_struct)); png_memset(png_ptr, 0, sizeof (png_struct));
memcpy(png_ptr->jmpbuf, tmp_jmp, sizeof (jmp_buf)); png_memcpy(png_ptr->jmpbuf, tmp_jmp, sizeof (jmp_buf));
png_ptr->zbuf_size = PNG_ZBUF_SIZE; png_ptr->zbuf_size = PNG_ZBUF_SIZE;
png_ptr->zbuf = png_large_malloc(png_ptr, png_ptr->zbuf_size); png_ptr->zbuf = png_large_malloc(png_ptr, png_ptr->zbuf_size);
@ -63,9 +63,28 @@ png_read_info(png_struct *png_ptr, png_info *info)
if (png_ptr->mode != PNG_HAVE_IHDR) if (png_ptr->mode != PNG_HAVE_IHDR)
png_error(png_ptr, "Missing IHDR"); png_error(png_ptr, "Missing IHDR");
#if !defined(PNG_READ_OPT_PLTE_SUPPORTED)
if (png_ptr->color_type != PNG_COLOR_TYPE_PALETTE)
png_crc_skip(png_ptr, length);
else
#else
{
png_handle_PLTE(png_ptr, info, length); png_handle_PLTE(png_ptr, info, length);
}
#endif
png_ptr->mode = PNG_HAVE_PLTE; png_ptr->mode = PNG_HAVE_PLTE;
} }
else if (!memcmp(chunk_start + 4, png_IDAT, 4))
{
png_ptr->idat_size = length;
png_ptr->mode = PNG_HAVE_IDAT;
break;
}
else if (!memcmp(chunk_start + 4, png_IEND, 4))
{
png_error(png_ptr, "No Image in File");
}
#if defined(PNG_READ_gAMA_SUPPORTED)
else if (!memcmp(chunk_start + 4, png_gAMA, 4)) else if (!memcmp(chunk_start + 4, png_gAMA, 4))
{ {
if (png_ptr->mode != PNG_HAVE_IHDR) if (png_ptr->mode != PNG_HAVE_IHDR)
@ -73,6 +92,8 @@ png_read_info(png_struct *png_ptr, png_info *info)
png_handle_gAMA(png_ptr, info, length); png_handle_gAMA(png_ptr, info, length);
} }
#endif
#if defined(PNG_READ_sBIT_SUPPORTED)
else if (!memcmp(chunk_start + 4, png_sBIT, 4)) else if (!memcmp(chunk_start + 4, png_sBIT, 4))
{ {
if (png_ptr->mode != PNG_HAVE_IHDR) if (png_ptr->mode != PNG_HAVE_IHDR)
@ -80,6 +101,8 @@ png_read_info(png_struct *png_ptr, png_info *info)
png_handle_sBIT(png_ptr, info, length); png_handle_sBIT(png_ptr, info, length);
} }
#endif
#if defined(PNG_READ_cHRM_SUPPORTED)
else if (!memcmp(chunk_start + 4, png_cHRM, 4)) else if (!memcmp(chunk_start + 4, png_cHRM, 4))
{ {
if (png_ptr->mode != PNG_HAVE_IHDR) if (png_ptr->mode != PNG_HAVE_IHDR)
@ -87,6 +110,8 @@ png_read_info(png_struct *png_ptr, png_info *info)
png_handle_cHRM(png_ptr, info, length); png_handle_cHRM(png_ptr, info, length);
} }
#endif
#if defined(PNG_READ_tRNS_SUPPORTED)
else if (!memcmp(chunk_start + 4, png_tRNS, 4)) else if (!memcmp(chunk_start + 4, png_tRNS, 4))
{ {
if (png_ptr->mode != PNG_HAVE_IHDR && if (png_ptr->mode != PNG_HAVE_IHDR &&
@ -95,6 +120,8 @@ png_read_info(png_struct *png_ptr, png_info *info)
png_handle_tRNS(png_ptr, info, length); png_handle_tRNS(png_ptr, info, length);
} }
#endif
#if defined(PNG_READ_bKGD_SUPPORTED)
else if (!memcmp(chunk_start + 4, png_bKGD, 4)) else if (!memcmp(chunk_start + 4, png_bKGD, 4))
{ {
if (png_ptr->mode != PNG_HAVE_IHDR && if (png_ptr->mode != PNG_HAVE_IHDR &&
@ -103,6 +130,8 @@ png_read_info(png_struct *png_ptr, png_info *info)
png_handle_bKGD(png_ptr, info, length); png_handle_bKGD(png_ptr, info, length);
} }
#endif
#if defined(PNG_READ_hIST_SUPPORTED)
else if (!memcmp(chunk_start + 4, png_hIST, 4)) else if (!memcmp(chunk_start + 4, png_hIST, 4))
{ {
if (png_ptr->mode != PNG_HAVE_PLTE) if (png_ptr->mode != PNG_HAVE_PLTE)
@ -110,12 +139,8 @@ png_read_info(png_struct *png_ptr, png_info *info)
png_handle_hIST(png_ptr, info, length); png_handle_hIST(png_ptr, info, length);
} }
else if (!memcmp(chunk_start + 4, png_IDAT, 4)) #endif
{ #if defined(PNG_READ_pHYs_SUPPORTED)
png_ptr->idat_size = length;
png_ptr->mode = PNG_HAVE_IDAT;
break;
}
else if (!memcmp(chunk_start + 4, png_pHYs, 4)) else if (!memcmp(chunk_start + 4, png_pHYs, 4))
{ {
if (png_ptr->mode != PNG_HAVE_IHDR && if (png_ptr->mode != PNG_HAVE_IHDR &&
@ -124,6 +149,8 @@ png_read_info(png_struct *png_ptr, png_info *info)
png_handle_pHYs(png_ptr, info, length); png_handle_pHYs(png_ptr, info, length);
} }
#endif
#if defined(PNG_READ_oFFs_SUPPORTED)
else if (!memcmp(chunk_start + 4, png_oFFs, 4)) else if (!memcmp(chunk_start + 4, png_oFFs, 4))
{ {
if (png_ptr->mode != PNG_HAVE_IHDR && if (png_ptr->mode != PNG_HAVE_IHDR &&
@ -132,6 +159,8 @@ png_read_info(png_struct *png_ptr, png_info *info)
png_handle_oFFs(png_ptr, info, length); png_handle_oFFs(png_ptr, info, length);
} }
#endif
#if defined(PNG_READ_tIME_SUPPORTED)
else if (!memcmp(chunk_start + 4, png_tIME, 4)) else if (!memcmp(chunk_start + 4, png_tIME, 4))
{ {
if (png_ptr->mode == PNG_BEFORE_IHDR || if (png_ptr->mode == PNG_BEFORE_IHDR ||
@ -140,6 +169,8 @@ png_read_info(png_struct *png_ptr, png_info *info)
png_handle_tIME(png_ptr, info, length); png_handle_tIME(png_ptr, info, length);
} }
#endif
#if defined(PNG_READ_tEXt_SUPPORTED)
else if (!memcmp(chunk_start + 4, png_tEXt, 4)) else if (!memcmp(chunk_start + 4, png_tEXt, 4))
{ {
if (png_ptr->mode == PNG_BEFORE_IHDR || if (png_ptr->mode == PNG_BEFORE_IHDR ||
@ -148,6 +179,8 @@ png_read_info(png_struct *png_ptr, png_info *info)
png_handle_tEXt(png_ptr, info, length); png_handle_tEXt(png_ptr, info, length);
} }
#endif
#if defined(PNG_READ_zTXt_SUPPORTED)
else if (!memcmp(chunk_start + 4, png_zTXt, 4)) else if (!memcmp(chunk_start + 4, png_zTXt, 4))
{ {
if (png_ptr->mode == PNG_BEFORE_IHDR || if (png_ptr->mode == PNG_BEFORE_IHDR ||
@ -156,13 +189,10 @@ png_read_info(png_struct *png_ptr, png_info *info)
png_handle_zTXt(png_ptr, info, length); png_handle_zTXt(png_ptr, info, length);
} }
else if (!memcmp(chunk_start + 4, png_IEND, 4)) #endif
{
png_error(png_ptr, "No Image in File");
}
else else
{ {
if (isupper(chunk_start[4])) if ((chunk_start[4] & 0x20) == 0)
png_error(png_ptr, "Unknown Critical Chunk"); png_error(png_ptr, "Unknown Critical Chunk");
png_crc_skip(png_ptr, length); png_crc_skip(png_ptr, length);
@ -175,6 +205,15 @@ png_read_info(png_struct *png_ptr, png_info *info)
} }
} }
/* optional call to update the users info structure */
void
png_read_update_info(png_struct *png_ptr, png_info *info_ptr)
{
if (!(png_ptr->row_init))
png_read_start_row(png_ptr);
png_read_transform_info(png_ptr, info_ptr);
}
/* initialize palette, background, etc, after transformations /* initialize palette, background, etc, after transformations
are set, but before any reading takes place. This allows are set, but before any reading takes place. This allows
the user to obtail a gamma corrected palette, for example. the user to obtail a gamma corrected palette, for example.
@ -182,17 +221,18 @@ png_read_info(png_struct *png_ptr, png_info *info)
void void
png_start_read_image(png_struct *png_ptr) png_start_read_image(png_struct *png_ptr)
{ {
if (!(png_ptr->row_init))
png_read_start_row(png_ptr); png_read_start_row(png_ptr);
} }
void void
png_read_row(png_struct *png_ptr, png_byte *row, png_byte *dsp_row) png_read_row(png_struct *png_ptr, png_bytef *row, png_byte *dsp_row)
{ {
int ret; int ret;
if (!(png_ptr->row_init)) if (!(png_ptr->row_init))
png_read_start_row(png_ptr); png_read_start_row(png_ptr);
#if defined(PNG_READ_INTERLACING_SUPPORTED)
/* if interlaced and we do not need a new row, combine row and return */ /* if interlaced and we do not need a new row, combine row and return */
if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE)) if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
{ {
@ -267,6 +307,7 @@ png_read_row(png_struct *png_ptr, png_byte *row, png_byte *dsp_row)
break; break;
} }
} }
#endif
if (png_ptr->mode != PNG_HAVE_IDAT) if (png_ptr->mode != PNG_HAVE_IDAT)
png_error(png_ptr, "invalid attempt to read row data"); png_error(png_ptr, "invalid attempt to read row data");
@ -334,11 +375,12 @@ png_read_row(png_struct *png_ptr, png_byte *row, png_byte *dsp_row)
png_ptr->row_buf + 1, png_ptr->prev_row + 1, png_ptr->row_buf + 1, png_ptr->prev_row + 1,
(int)(png_ptr->row_buf[0])); (int)(png_ptr->row_buf[0]));
memcpy(png_ptr->prev_row, png_ptr->row_buf, (png_size_t)png_ptr->rowbytes + 1); png_memcpy(png_ptr->prev_row, png_ptr->row_buf, (png_size_t)png_ptr->rowbytes + 1);
if (png_ptr->transformations) if (png_ptr->transformations)
png_do_read_transformations(png_ptr); png_do_read_transformations(png_ptr);
#if defined(PNG_READ_INTERLACING_SUPPORTED)
/* blow up interlaced rows to full size */ /* blow up interlaced rows to full size */
if (png_ptr->interlaced && if (png_ptr->interlaced &&
(png_ptr->transformations & PNG_INTERLACE)) (png_ptr->transformations & PNG_INTERLACE))
@ -355,6 +397,7 @@ png_read_row(png_struct *png_ptr, png_byte *row, png_byte *dsp_row)
png_pass_mask[png_ptr->pass]); png_pass_mask[png_ptr->pass]);
} }
else else
#endif
{ {
if (row) if (row)
png_combine_row(png_ptr, row, 0xff); png_combine_row(png_ptr, row, 0xff);
@ -383,18 +426,18 @@ png_read_row(png_struct *png_ptr, png_byte *row, png_byte *dsp_row)
not called png_set_interlace_handling(), the display_row buffer will not called png_set_interlace_handling(), the display_row buffer will
be ignored, so pass NULL to it. */ be ignored, so pass NULL to it. */
void void
png_read_rows(png_struct *png_ptr, png_byte **row, png_read_rows(png_struct *png_ptr, png_bytef **row,
png_byte **display_row, png_uint_32 num_rows) png_byte **display_row, png_uint_32 num_rows)
{ {
png_uint_32 i; png_uint_32 i;
png_byte **rp; png_bytef **rp;
png_byte **dp; png_byte **dp;
rp = row; rp = row;
dp = display_row; dp = display_row;
for (i = 0; i < num_rows; i++) for (i = 0; i < num_rows; i++)
{ {
png_byte *rptr; png_bytef *rptr;
png_byte *dptr; png_byte *dptr;
if (rp) if (rp)
@ -420,11 +463,11 @@ png_read_rows(png_struct *png_ptr, png_byte **row,
You only need to call this function once. If you desire to have You only need to call this function once. If you desire to have
an image for each pass of a interlaced image, use png_read_rows() */ an image for each pass of a interlaced image, use png_read_rows() */
void void
png_read_image(png_struct *png_ptr, png_byte **image) png_read_image(png_struct *png_ptr, png_bytef **image)
{ {
png_uint_32 i; png_uint_32 i;
int pass, j; int pass, j;
png_byte **rp; png_bytef **rp;
pass = png_set_interlace_handling(png_ptr); pass = png_set_interlace_handling(png_ptr);
for (j = 0; j < pass; j++) for (j = 0; j < pass; j++)
@ -506,6 +549,7 @@ png_read_end(png_struct *png_ptr, png_info *info)
{ {
png_error(png_ptr, "invalid chunk after IDAT"); png_error(png_ptr, "invalid chunk after IDAT");
} }
#if defined(PNG_READ_tIME_SUPPORTED)
else if (!memcmp(chunk_start + 4, png_tIME, 4)) else if (!memcmp(chunk_start + 4, png_tIME, 4))
{ {
if (png_ptr->mode == PNG_BEFORE_IHDR || if (png_ptr->mode == PNG_BEFORE_IHDR ||
@ -517,6 +561,8 @@ png_read_end(png_struct *png_ptr, png_info *info)
else else
png_crc_skip(png_ptr, length); png_crc_skip(png_ptr, length);
} }
#endif
#if defined(PNG_READ_tEXt_SUPPORTED)
else if (!memcmp(chunk_start + 4, png_tEXt, 4)) else if (!memcmp(chunk_start + 4, png_tEXt, 4))
{ {
if (png_ptr->mode == PNG_BEFORE_IHDR || if (png_ptr->mode == PNG_BEFORE_IHDR ||
@ -528,6 +574,8 @@ png_read_end(png_struct *png_ptr, png_info *info)
else else
png_crc_skip(png_ptr, length); png_crc_skip(png_ptr, length);
} }
#endif
#if defined(PNG_READ_zTXt_SUPPORTED)
else if (!memcmp(chunk_start + 4, png_zTXt, 4)) else if (!memcmp(chunk_start + 4, png_zTXt, 4))
{ {
if (png_ptr->mode == PNG_BEFORE_IHDR || if (png_ptr->mode == PNG_BEFORE_IHDR ||
@ -539,13 +587,14 @@ png_read_end(png_struct *png_ptr, png_info *info)
else else
png_crc_skip(png_ptr, length); png_crc_skip(png_ptr, length);
} }
#endif
else if (!memcmp(chunk_start + 4, png_IEND, 4)) else if (!memcmp(chunk_start + 4, png_IEND, 4))
{ {
png_ptr->mode = PNG_AFTER_IEND; png_ptr->mode = PNG_AFTER_IEND;
} }
else else
{ {
if (isupper(chunk_start[4])) if ((chunk_start[4] & 0x20) == 0)
png_error(png_ptr, "Unknown Critical Chunk"); png_error(png_ptr, "Unknown Critical Chunk");
png_crc_skip(png_ptr, length); png_crc_skip(png_ptr, length);
@ -569,40 +618,58 @@ png_read_destroy(png_struct *png_ptr, png_info *info, png_info *end_info)
if (info) if (info)
{ {
/* I'm not sure I should be freeing this */
if (info->palette != png_ptr->palette) if (info->palette != png_ptr->palette)
png_free(png_ptr, info->palette); png_free(png_ptr, info->palette);
/* I'm not sure I should be freeing this */
#if defined(PNG_READ_BACKGROUND_SUPPORTED) && defined(PNG_READ_bKGD_SUPPORTED)
if (info->trans != png_ptr->trans) if (info->trans != png_ptr->trans)
png_free(png_ptr, info->trans); png_free(png_ptr, info->trans);
#endif
/* I'm not sure I should be freeing this */
#if defined(PNG_READ_hIST_SUPPORTED)
if (info->hist != png_ptr->hist) if (info->hist != png_ptr->hist)
png_free(png_ptr, info->hist); png_free(png_ptr, info->hist);
#endif
#if defined(PNG_READ_tEXt_SUPPORTED) || defined(PNG_READ_zTXt_SUPPORTED)
for (i = 0; i < info->num_text; i++) for (i = 0; i < info->num_text; i++)
{ {
png_large_free(png_ptr, info->text[i].key); png_large_free(png_ptr, info->text[i].key);
} }
png_free(png_ptr, info->text); png_free(png_ptr, info->text);
memset(info, 0, sizeof(png_info)); #endif
png_memset(info, 0, sizeof(png_info));
} }
if (end_info) if (end_info)
{ {
#if defined(PNG_READ_tEXt_SUPPORTED) || defined(PNG_READ_zTXt_SUPPORTED)
for (i = 0; i < end_info->num_text; i++) for (i = 0; i < end_info->num_text; i++)
{ {
png_large_free(png_ptr, end_info->text[i].key); png_large_free(png_ptr, end_info->text[i].key);
} }
png_free(png_ptr, end_info->text); png_free(png_ptr, end_info->text);
memset(end_info, 0, sizeof(png_info)); #endif
png_memset(end_info, 0, sizeof(png_info));
} }
png_large_free(png_ptr, png_ptr->zbuf); png_large_free(png_ptr, png_ptr->zbuf);
png_large_free(png_ptr, png_ptr->row_buf); png_large_free(png_ptr, png_ptr->row_buf);
png_large_free(png_ptr, png_ptr->prev_row); png_large_free(png_ptr, png_ptr->prev_row);
#if defined(PNG_READ_DITHER_SUPPORTED)
png_large_free(png_ptr, png_ptr->palette_lookup); png_large_free(png_ptr, png_ptr->palette_lookup);
png_free(png_ptr, png_ptr->dither_index); png_free(png_ptr, png_ptr->dither_index);
#endif
#if defined(PNG_READ_GAMMA_SUPPORTED)
png_free(png_ptr, png_ptr->gamma_table); png_free(png_ptr, png_ptr->gamma_table);
#endif
#if defined(PNG_READ_BACKGROUND_SUPPORTED)
png_free(png_ptr, png_ptr->gamma_from_1); png_free(png_ptr, png_ptr->gamma_from_1);
png_free(png_ptr, png_ptr->gamma_to_1); png_free(png_ptr, png_ptr->gamma_to_1);
#endif
#if defined(PNG_READ_GAMMA_SUPPORTED)
if (png_ptr->gamma_16_table) if (png_ptr->gamma_16_table)
{ {
for (i = 0; i < (1 << (8 - png_ptr->gamma_shift)); i++) for (i = 0; i < (1 << (8 - png_ptr->gamma_shift)); i++)
@ -610,6 +677,8 @@ png_read_destroy(png_struct *png_ptr, png_info *info, png_info *end_info)
png_free(png_ptr, png_ptr->gamma_16_table[i]); png_free(png_ptr, png_ptr->gamma_16_table[i]);
} }
} }
#endif
#if defined(PNG_READ_BACKGROUND_SUPPORTED)
png_free(png_ptr, png_ptr->gamma_16_table); png_free(png_ptr, png_ptr->gamma_16_table);
if (png_ptr->gamma_16_from_1) if (png_ptr->gamma_16_from_1)
{ {
@ -627,16 +696,20 @@ png_read_destroy(png_struct *png_ptr, png_info *info, png_info *end_info)
} }
} }
png_free(png_ptr, png_ptr->gamma_16_to_1); png_free(png_ptr, png_ptr->gamma_16_to_1);
#endif
#if defined(PNG_READ_BACKGROUND_SUPPORTED)
png_free(png_ptr, png_ptr->trans); png_free(png_ptr, png_ptr->trans);
#endif
#if defined(PNG_READ_DITHER_SUPPORTED)
png_free(png_ptr, png_ptr->hist); png_free(png_ptr, png_ptr->hist);
#endif
if (!png_ptr->user_palette) if (!png_ptr->user_palette)
png_free(png_ptr, png_ptr->palette); png_free(png_ptr, png_ptr->palette);
inflateEnd(png_ptr->zstream); inflateEnd(png_ptr->zstream);
memcpy(tmp_jmp, png_ptr->jmpbuf, sizeof (jmp_buf)); png_memcpy(tmp_jmp, png_ptr->jmpbuf, sizeof (jmp_buf));
memset(png_ptr, 0, sizeof (png_struct)); png_memset(png_ptr, 0, sizeof (png_struct));
memcpy(png_ptr->jmpbuf, tmp_jmp, sizeof (jmp_buf)); png_memcpy(png_ptr->jmpbuf, tmp_jmp, sizeof (jmp_buf));
} }

595
pngrtran.c
View File

File diff suppressed because it is too large Load Diff

137
pngrutil.c
View File

@ -1,10 +1,10 @@
/* pngrutil.c - utilities to read a png file /* pngrutil.c - utilities to read a png file
libpng 1.0 beta 1 - version 0.71 libpng 1.0 beta 2 - version 0.81
For conditions of distribution and use, see copyright notice in png.h For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc. Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
June 26, 1995 August 24, 1995
*/ */
#define PNG_INTERNAL #define PNG_INTERNAL
@ -38,7 +38,7 @@ png_get_uint_16(png_byte *buf)
/* read data, and run it through the crc */ /* read data, and run it through the crc */
void void
png_crc_read(png_struct *png_ptr, png_byte *buf, png_uint_32 length) png_crc_read(png_struct *png_ptr, png_bytef *buf, png_uint_32 length)
{ {
png_read_data(png_ptr, buf, length); png_read_data(png_ptr, buf, length);
png_calculate_crc(png_ptr, buf, length); png_calculate_crc(png_ptr, buf, length);
@ -179,6 +179,7 @@ png_handle_PLTE(png_struct *png_ptr, png_info *info, png_uint_32 length)
png_read_PLTE(png_ptr, info, palette, num); png_read_PLTE(png_ptr, info, palette, num);
} }
#if defined(PNG_READ_gAMA_SUPPORTED)
void void
png_handle_gAMA(png_struct *png_ptr, png_info *info, png_uint_32 length) png_handle_gAMA(png_struct *png_ptr, png_info *info, png_uint_32 length)
{ {
@ -202,7 +203,9 @@ png_handle_gAMA(png_struct *png_ptr, png_info *info, png_uint_32 length)
png_read_gAMA(png_ptr, info, gamma); png_read_gAMA(png_ptr, info, gamma);
png_ptr->gamma = gamma; png_ptr->gamma = gamma;
} }
#endif
#if defined(PNG_READ_sBIT_SUPPORTED)
void void
png_handle_sBIT(png_struct *png_ptr, png_info *info, png_uint_32 length) png_handle_sBIT(png_struct *png_ptr, png_info *info, png_uint_32 length)
{ {
@ -235,7 +238,9 @@ png_handle_sBIT(png_struct *png_ptr, png_info *info, png_uint_32 length)
} }
png_read_sBIT(png_ptr, info, &(png_ptr->sig_bit)); png_read_sBIT(png_ptr, info, &(png_ptr->sig_bit));
} }
#endif
#if defined(PNG_READ_cHRM_SUPPORTED)
void void
png_handle_cHRM(png_struct *png_ptr, png_info *info, png_uint_32 length) png_handle_cHRM(png_struct *png_ptr, png_info *info, png_uint_32 length)
{ {
@ -284,7 +289,9 @@ png_handle_cHRM(png_struct *png_ptr, png_info *info, png_uint_32 length)
png_read_cHRM(png_ptr, info, png_read_cHRM(png_ptr, info,
white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y); white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y);
} }
#endif
#if defined(PNG_READ_tRNS_SUPPORTED)
void void
png_handle_tRNS(png_struct *png_ptr, png_info *info, png_uint_32 length) png_handle_tRNS(png_struct *png_ptr, png_info *info, png_uint_32 length)
{ {
@ -336,7 +343,9 @@ png_handle_tRNS(png_struct *png_ptr, png_info *info, png_uint_32 length)
png_read_tRNS(png_ptr, info, png_ptr->trans, png_ptr->num_trans, png_read_tRNS(png_ptr, info, png_ptr->trans, png_ptr->num_trans,
&(png_ptr->trans_values)); &(png_ptr->trans_values));
} }
#endif
#if defined(PNG_READ_bKGD_SUPPORTED)
void void
png_handle_bKGD(png_struct *png_ptr, png_info *info, png_uint_32 length) png_handle_bKGD(png_struct *png_ptr, png_info *info, png_uint_32 length)
{ {
@ -370,7 +379,9 @@ png_handle_bKGD(png_struct *png_ptr, png_info *info, png_uint_32 length)
png_read_bKGD(png_ptr, info, &(png_ptr->background)); png_read_bKGD(png_ptr, info, &(png_ptr->background));
} }
#endif
#if defined(PNG_READ_hIST_SUPPORTED)
void void
png_handle_hIST(png_struct *png_ptr, png_info *info, png_uint_32 length) png_handle_hIST(png_struct *png_ptr, png_info *info, png_uint_32 length)
{ {
@ -393,7 +404,9 @@ png_handle_hIST(png_struct *png_ptr, png_info *info, png_uint_32 length)
} }
png_read_hIST(png_ptr, info, png_ptr->hist); png_read_hIST(png_ptr, info, png_ptr->hist);
} }
#endif
#if defined(PNG_READ_pHYs_SUPPORTED)
void void
png_handle_pHYs(png_struct *png_ptr, png_info *info, png_uint_32 length) png_handle_pHYs(png_struct *png_ptr, png_info *info, png_uint_32 length)
{ {
@ -414,7 +427,9 @@ png_handle_pHYs(png_struct *png_ptr, png_info *info, png_uint_32 length)
unit_type = buf[8]; unit_type = buf[8];
png_read_pHYs(png_ptr, info, res_x, res_y, unit_type); png_read_pHYs(png_ptr, info, res_x, res_y, unit_type);
} }
#endif
#if defined(PNG_READ_oFFs_SUPPORTED)
void void
png_handle_oFFs(png_struct *png_ptr, png_info *info, png_uint_32 length) png_handle_oFFs(png_struct *png_ptr, png_info *info, png_uint_32 length)
{ {
@ -435,7 +450,9 @@ png_handle_oFFs(png_struct *png_ptr, png_info *info, png_uint_32 length)
unit_type = buf[8]; unit_type = buf[8];
png_read_oFFs(png_ptr, info, offset_x, offset_y, unit_type); png_read_oFFs(png_ptr, info, offset_x, offset_y, unit_type);
} }
#endif
#if defined(PNG_READ_tIME_SUPPORTED)
void void
png_handle_tIME(png_struct *png_ptr, png_info *info, png_uint_32 length) png_handle_tIME(png_struct *png_ptr, png_info *info, png_uint_32 length)
{ {
@ -459,17 +476,20 @@ png_handle_tIME(png_struct *png_ptr, png_info *info, png_uint_32 length)
png_read_tIME(png_ptr, info, &mod_time); png_read_tIME(png_ptr, info, &mod_time);
} }
#endif
#if defined(PNG_READ_tEXt_SUPPORTED)
/* note: this does not correctly handle chunks that are > 64K */ /* note: this does not correctly handle chunks that are > 64K */
void void
png_handle_tEXt(png_struct *png_ptr, png_info *info, png_uint_32 length) png_handle_tEXt(png_struct *png_ptr, png_info *info, png_uint_32 length)
{ {
char *key, *text; charf *key;
charf *text;
text = NULL; text = NULL;
key = (char *)png_large_malloc(png_ptr, length + 1); key = (charf *)png_large_malloc(png_ptr, length + 1);
png_crc_read(png_ptr, (png_byte *)key, length); png_crc_read(png_ptr, (png_bytef *)key, length);
key[(png_size_t)length] = '\0'; key[(png_size_t)length] = '\0';
for (text = key; *text; text++) for (text = key; *text; text++)
@ -480,19 +500,22 @@ png_handle_tEXt(png_struct *png_ptr, png_info *info, png_uint_32 length)
png_read_tEXt(png_ptr, info, key, text, length - (text - key)); png_read_tEXt(png_ptr, info, key, text, length - (text - key));
} }
#endif
#if defined(PNG_READ_zTXt_SUPPORTED)
/* note: this does not correctly handle chunks that are > 64K compressed */ /* note: this does not correctly handle chunks that are > 64K compressed */
void void
png_handle_zTXt(png_struct *png_ptr, png_info *info, png_uint_32 length) png_handle_zTXt(png_struct *png_ptr, png_info *info, png_uint_32 length)
{ {
char *key, *text; charf *key;
charf *text;
int ret; int ret;
png_uint_32 text_size, key_size; png_uint_32 text_size, key_size;
text = NULL; text = NULL;
key = png_large_malloc(png_ptr, length + 1); key = png_large_malloc(png_ptr, length + 1);
png_crc_read(png_ptr, (png_byte *)key, length); png_crc_read(png_ptr, (png_bytef *)key, length);
key[(png_size_t)length] = '\0'; key[(png_size_t)length] = '\0';
for (text = key; *text; text++) for (text = key; *text; text++)
@ -515,7 +538,7 @@ png_handle_zTXt(png_struct *png_ptr, png_info *info, png_uint_32 length)
text++; text++;
png_ptr->zstream->next_in = (png_byte *)text; png_ptr->zstream->next_in = (png_bytef *)text;
png_ptr->zstream->avail_in = (uInt)(length - (text - key)); png_ptr->zstream->avail_in = (uInt)(length - (text - key));
png_ptr->zstream->next_out = png_ptr->zbuf; png_ptr->zstream->next_out = png_ptr->zbuf;
png_ptr->zstream->avail_out = (png_size_t)png_ptr->zbuf_size; png_ptr->zstream->avail_out = (png_size_t)png_ptr->zbuf_size;
@ -542,23 +565,23 @@ png_handle_zTXt(png_struct *png_ptr, png_info *info, png_uint_32 length)
text = png_malloc(png_ptr, text = png_malloc(png_ptr,
png_ptr->zbuf_size - png_ptr->zstream->avail_out + png_ptr->zbuf_size - png_ptr->zstream->avail_out +
key_size + 1); key_size + 1);
memcpy(text + (png_size_t)key_size, png_ptr->zbuf, png_memcpy(text + (png_size_t)key_size, png_ptr->zbuf,
(png_size_t)(png_ptr->zbuf_size - png_ptr->zstream->avail_out)); (png_size_t)(png_ptr->zbuf_size - png_ptr->zstream->avail_out));
memcpy(text, key, (png_size_t)key_size); png_memcpy(text, key, (png_size_t)key_size);
text_size = key_size + (png_size_t)png_ptr->zbuf_size - text_size = key_size + (png_size_t)png_ptr->zbuf_size -
png_ptr->zstream->avail_out; png_ptr->zstream->avail_out;
*(text + (png_size_t)text_size) = '\0'; *(text + (png_size_t)text_size) = '\0';
} }
else else
{ {
char *tmp; charf *tmp;
tmp = text; tmp = text;
text = png_large_malloc(png_ptr, text_size + text = png_large_malloc(png_ptr, text_size +
png_ptr->zbuf_size - png_ptr->zstream->avail_out + 1); png_ptr->zbuf_size - png_ptr->zstream->avail_out + 1);
memcpy(text, tmp, (png_size_t)text_size); png_memcpy(text, tmp, (png_size_t)text_size);
png_large_free(png_ptr, tmp); png_large_free(png_ptr, tmp);
memcpy(text + (png_size_t)text_size, png_ptr->zbuf, png_memcpy(text + (png_size_t)text_size, png_ptr->zbuf,
(png_size_t)(png_ptr->zbuf_size - png_ptr->zstream->avail_out)); (png_size_t)(png_ptr->zbuf_size - png_ptr->zstream->avail_out));
text_size += png_ptr->zbuf_size - png_ptr->zstream->avail_out; text_size += png_ptr->zbuf_size - png_ptr->zstream->avail_out;
*(text + (png_size_t)text_size) = '\0'; *(text + (png_size_t)text_size) = '\0';
@ -595,6 +618,7 @@ png_handle_zTXt(png_struct *png_ptr, png_info *info, png_uint_32 length)
png_read_zTXt(png_ptr, info, key, text, text_size, 0); png_read_zTXt(png_ptr, info, key, text, text_size, 0);
} }
#endif
/* Combines the row recently read in with the previous row. /* Combines the row recently read in with the previous row.
This routine takes care of alpha and transparency if requested. This routine takes care of alpha and transparency if requested.
@ -608,12 +632,12 @@ png_handle_zTXt(png_struct *png_ptr, png_info *info, png_uint_32 length)
you want all pixels to be combined, pass 0xff (255) in mask. you want all pixels to be combined, pass 0xff (255) in mask.
*/ */
void void
png_combine_row(png_struct *png_ptr, png_byte *row, png_combine_row(png_struct *png_ptr, png_bytef *row,
int mask) int mask)
{ {
if (mask == 0xff) if (mask == 0xff)
{ {
memcpy(row, png_ptr->row_buf + 1, png_memcpy(row, png_ptr->row_buf + 1,
(png_size_t)((png_ptr->width * (png_size_t)((png_ptr->width *
png_ptr->row_info.pixel_depth + 7) >> 3)); png_ptr->row_info.pixel_depth + 7) >> 3));
} }
@ -623,8 +647,8 @@ png_combine_row(png_struct *png_ptr, png_byte *row,
{ {
case 1: case 1:
{ {
png_byte *sp; png_bytef *sp;
png_byte *dp; png_bytef *dp;
int m; int m;
int shift; int shift;
png_uint_32 i; png_uint_32 i;
@ -661,8 +685,8 @@ png_combine_row(png_struct *png_ptr, png_byte *row,
} }
case 2: case 2:
{ {
png_byte *sp; png_bytef *sp;
png_byte *dp; png_bytef *dp;
int m; int m;
int shift; int shift;
png_uint_32 i; png_uint_32 i;
@ -698,8 +722,8 @@ png_combine_row(png_struct *png_ptr, png_byte *row,
} }
case 4: case 4:
{ {
png_byte *sp; png_bytef *sp;
png_byte *dp; png_bytef *dp;
int m; int m;
int shift; int shift;
png_uint_32 i; png_uint_32 i;
@ -735,8 +759,8 @@ png_combine_row(png_struct *png_ptr, png_byte *row,
} }
default: default:
{ {
png_byte *sp; png_bytef *sp;
png_byte *dp; png_bytef *dp;
png_uint_32 i; png_uint_32 i;
int pixel_bytes, m; int pixel_bytes, m;
@ -749,7 +773,7 @@ png_combine_row(png_struct *png_ptr, png_byte *row,
{ {
if (m & mask) if (m & mask)
{ {
memcpy(dp, sp, pixel_bytes); png_memcpy(dp, sp, pixel_bytes);
} }
sp += pixel_bytes; sp += pixel_bytes;
@ -766,8 +790,9 @@ png_combine_row(png_struct *png_ptr, png_byte *row,
} }
} }
#if defined(PNG_READ_INTERLACING_SUPPORTED)
void void
png_do_read_interlace(png_row_info *row_info, png_byte *row, int pass) png_do_read_interlace(png_row_info *row_info, png_bytef *row, int pass)
{ {
if (row && row_info) if (row && row_info)
{ {
@ -779,7 +804,7 @@ png_do_read_interlace(png_row_info *row_info, png_byte *row, int pass)
{ {
case 1: case 1:
{ {
png_byte *sp, *dp; png_bytef *sp, *dp;
int sshift, dshift; int sshift, dshift;
png_byte v; png_byte v;
png_uint_32 i; png_uint_32 i;
@ -816,7 +841,7 @@ png_do_read_interlace(png_row_info *row_info, png_byte *row, int pass)
} }
case 2: case 2:
{ {
png_byte *sp, *dp; png_bytef *sp, *dp;
int sshift, dshift; int sshift, dshift;
png_byte v; png_byte v;
png_uint_32 i, j; png_uint_32 i, j;
@ -852,7 +877,7 @@ png_do_read_interlace(png_row_info *row_info, png_byte *row, int pass)
} }
case 4: case 4:
{ {
png_byte *sp, *dp; png_bytef *sp, *dp;
int sshift, dshift; int sshift, dshift;
png_byte v; png_byte v;
png_uint_32 i; png_uint_32 i;
@ -889,7 +914,7 @@ png_do_read_interlace(png_row_info *row_info, png_byte *row, int pass)
} }
default: default:
{ {
png_byte *sp, *dp; png_bytef *sp, *dp;
png_byte v[8]; png_byte v[8];
png_uint_32 i; png_uint_32 i;
int j; int j;
@ -901,10 +926,10 @@ png_do_read_interlace(png_row_info *row_info, png_byte *row, int pass)
dp = row + (png_size_t)((final_width - 1) * pixel_bytes); dp = row + (png_size_t)((final_width - 1) * pixel_bytes);
for (i = row_info->width; i; i--) for (i = row_info->width; i; i--)
{ {
memcpy(v, sp, pixel_bytes); png_memcpy(v, sp, pixel_bytes);
for (j = 0; j < png_pass_inc[pass]; j++) for (j = 0; j < png_pass_inc[pass]; j++)
{ {
memcpy(dp, v, pixel_bytes); png_memcpy(dp, v, pixel_bytes);
dp -= pixel_bytes; dp -= pixel_bytes;
} }
sp -= pixel_bytes; sp -= pixel_bytes;
@ -917,10 +942,11 @@ png_do_read_interlace(png_row_info *row_info, png_byte *row, int pass)
(png_uint_32)row_info->pixel_depth + 7) >> 3); (png_uint_32)row_info->pixel_depth + 7) >> 3);
} }
} }
#endif
void void
png_read_filter_row(png_row_info *row_info, png_byte *row, png_read_filter_row(png_row_info *row_info, png_bytef *row,
png_byte *prev_row, int filter) png_bytef *prev_row, int filter)
{ {
switch (filter) switch (filter)
{ {
@ -930,8 +956,8 @@ png_read_filter_row(png_row_info *row_info, png_byte *row,
{ {
png_uint_32 i; png_uint_32 i;
int bpp; int bpp;
png_byte *rp; png_bytef *rp;
png_byte *lp; png_bytef *lp;
bpp = (row_info->pixel_depth + 7) / 8; bpp = (row_info->pixel_depth + 7) / 8;
for (i = (png_uint_32)bpp, rp = row + bpp, lp = row; for (i = (png_uint_32)bpp, rp = row + bpp, lp = row;
@ -944,8 +970,8 @@ png_read_filter_row(png_row_info *row_info, png_byte *row,
case 2: case 2:
{ {
png_uint_32 i; png_uint_32 i;
png_byte *rp; png_bytef *rp;
png_byte *pp; png_bytef *pp;
for (i = 0, rp = row, pp = prev_row; for (i = 0, rp = row, pp = prev_row;
i < row_info->rowbytes; i++, rp++, pp++) i < row_info->rowbytes; i++, rp++, pp++)
@ -958,9 +984,9 @@ png_read_filter_row(png_row_info *row_info, png_byte *row,
{ {
png_uint_32 i; png_uint_32 i;
int bpp; int bpp;
png_byte *rp; png_bytef *rp;
png_byte *pp; png_bytef *pp;
png_byte *lp; png_bytef *lp;
bpp = (row_info->pixel_depth + 7) / 8; bpp = (row_info->pixel_depth + 7) / 8;
for (i = 0, rp = row, pp = prev_row; for (i = 0, rp = row, pp = prev_row;
@ -980,10 +1006,10 @@ png_read_filter_row(png_row_info *row_info, png_byte *row,
{ {
int bpp; int bpp;
png_uint_32 i; png_uint_32 i;
png_byte *rp; png_bytef *rp;
png_byte *pp; png_bytef *pp;
png_byte *lp; png_bytef *lp;
png_byte *cp; png_bytef *cp;
bpp = (row_info->pixel_depth + 7) / 8; bpp = (row_info->pixel_depth + 7) / 8;
for (i = 0, rp = row, pp = prev_row, for (i = 0, rp = row, pp = prev_row,
@ -1033,7 +1059,7 @@ png_read_finish_row(png_struct *png_ptr)
if (png_ptr->interlaced) if (png_ptr->interlaced)
{ {
png_ptr->row_number = 0; png_ptr->row_number = 0;
memset(png_ptr->prev_row, 0, (png_size_t)png_ptr->rowbytes + 1); png_memset(png_ptr->prev_row, 0, (png_size_t)png_ptr->rowbytes + 1);
do do
{ {
png_ptr->pass++; png_ptr->pass++;
@ -1054,6 +1080,8 @@ png_read_finish_row(png_struct *png_ptr)
if (!(png_ptr->num_rows)) if (!(png_ptr->num_rows))
continue; continue;
} }
if (png_ptr->transformations & PNG_INTERLACE)
break;
} while (png_ptr->iwidth == 0); } while (png_ptr->iwidth == 0);
if (png_ptr->pass < 7) if (png_ptr->pass < 7)
@ -1157,11 +1185,14 @@ png_read_start_row(png_struct *png_ptr)
max_pixel_depth = png_ptr->pixel_depth; max_pixel_depth = png_ptr->pixel_depth;
#if defined(PNG_READ_PACK_SUPPORTED)
if ((png_ptr->transformations & PNG_PACK) && png_ptr->bit_depth < 8) if ((png_ptr->transformations & PNG_PACK) && png_ptr->bit_depth < 8)
{ {
max_pixel_depth = 8; max_pixel_depth = 8;
} }
#endif
#if defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_PACK_SUPPORTED)
if (png_ptr->transformations & (PNG_EXPAND | PNG_PACK)) if (png_ptr->transformations & (PNG_EXPAND | PNG_PACK))
{ {
if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
@ -1187,13 +1218,17 @@ png_read_start_row(png_struct *png_ptr)
} }
} }
} }
#endif
if (png_ptr->transformations & PNG_RGBA) #if defined(PNG_READ_FILLER_SUPPORTED)
if (png_ptr->transformations & (PNG_FILLER))
{ {
if (max_pixel_depth < 32) if (max_pixel_depth < 32)
max_pixel_depth = 32; max_pixel_depth = 32;
} }
#endif
#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
if (png_ptr->transformations & PNG_GRAY_TO_RGB) if (png_ptr->transformations & PNG_GRAY_TO_RGB)
{ {
if ((png_ptr->num_trans && (png_ptr->transformations & PNG_EXPAND)) || if ((png_ptr->num_trans && (png_ptr->transformations & PNG_EXPAND)) ||
@ -1212,6 +1247,7 @@ png_read_start_row(png_struct *png_ptr)
max_pixel_depth = 48; max_pixel_depth = 48;
} }
} }
#endif
/* align the width on the next larger 8 pixels. Mainly used /* align the width on the next larger 8 pixels. Mainly used
for interlacing */ for interlacing */
@ -1224,7 +1260,7 @@ png_read_start_row(png_struct *png_ptr)
if (rowbytes > 65536L) if (rowbytes > 65536L)
png_error(png_ptr, "This image requires a row greater then 64KB"); png_error(png_ptr, "This image requires a row greater then 64KB");
#endif #endif
png_ptr->row_buf = (png_byte *)png_large_malloc(png_ptr, rowbytes); png_ptr->row_buf = (png_bytef *)png_large_malloc(png_ptr, rowbytes);
#ifdef PNG_MAX_MALLOC_64K #ifdef PNG_MAX_MALLOC_64K
if (png_ptr->rowbytes + 1 > 65536L) if (png_ptr->rowbytes + 1 > 65536L)
@ -1233,11 +1269,8 @@ png_read_start_row(png_struct *png_ptr)
png_ptr->prev_row = png_large_malloc(png_ptr, png_ptr->prev_row = png_large_malloc(png_ptr,
png_ptr->rowbytes + 1); png_ptr->rowbytes + 1);
memset(png_ptr->prev_row, 0, (png_size_t)png_ptr->rowbytes + 1); png_memset(png_ptr->prev_row, 0, (png_size_t)png_ptr->rowbytes + 1);
png_ptr->row_init = 1; png_ptr->row_init = 1;
/* if we have to do any modifications of values for the transformations,
do them here */
} }

39
pngtest.c
View File

@ -1,9 +1,9 @@
/* pngtest.c - a simple test program to test libpng /* pngtest.c - a simple test program to test libpng
libpng 1.0 beta 1 - version 0.71 libpng 1.0 beta 2 - version 0.81
For conditions of distribution and use, see copyright notice in png.h For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc. Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
June 26, 1995 August 24, 1995
*/ */
#include <stdio.h> #include <stdio.h>
@ -38,19 +38,29 @@ int main()
row_buf = (png_byte *)0; row_buf = (png_byte *)0;
fprintf(STDERR, "Testing libpng version %s\n", PNG_LIBPNG_VER_STRING);
if (strcmp(png_libpng_ver, PNG_LIBPNG_VER_STRING))
{
fprintf(STDERR,
"Warning: versions are different between png.h and png.c\n");
fprintf(STDERR, " png.h version: %s\n", PNG_LIBPNG_VER_STRING);
fprintf(STDERR, " png.c version: %s\n\n", png_libpng_ver);
}
fpin = fopen(inname, "rb"); fpin = fopen(inname, "rb");
if (!fpin) if (!fpin)
{ {
fprintf(STDERR, "Could not find input file %s\n", inname); fprintf(STDERR, "Could not find input file %s\n", inname);
return -1; return 1;
} }
fpout = fopen(outname, "wb"); fpout = fopen(outname, "wb");
if (!fpin) if (!fpout)
{ {
fprintf(STDERR, "could not open output file %s\n", outname); fprintf(STDERR, "could not open output file %s\n", outname);
fclose(fpin); fclose(fpin);
return -1; return 1;
} }
if (setjmp(read_ptr.jmpbuf)) if (setjmp(read_ptr.jmpbuf))
@ -58,7 +68,7 @@ int main()
fprintf(STDERR, "libpng read error\n"); fprintf(STDERR, "libpng read error\n");
fclose(fpin); fclose(fpin);
fclose(fpout); fclose(fpout);
return -1; return 1;
} }
if (setjmp(write_ptr.jmpbuf)) if (setjmp(write_ptr.jmpbuf))
@ -66,7 +76,7 @@ int main()
fprintf(STDERR, "libpng write error\n"); fprintf(STDERR, "libpng write error\n");
fclose(fpin); fclose(fpin);
fclose(fpout); fclose(fpout);
return -1; return 1;
} }
png_read_init(&read_ptr); png_read_init(&read_ptr);
@ -96,7 +106,7 @@ int main()
png_write_destroy(&write_ptr); png_write_destroy(&write_ptr);
fclose(fpin); fclose(fpin);
fclose(fpout); fclose(fpout);
return -1; return 1;
} }
if (info_ptr.interlace_type) if (info_ptr.interlace_type)
@ -113,8 +123,8 @@ int main()
{ {
for (y = 0; y < info_ptr.height; y++) for (y = 0; y < info_ptr.height; y++)
{ {
png_read_rows(&read_ptr, &row_buf, (png_byte **)0, 1); png_read_rows(&read_ptr, (png_bytef **)&row_buf, (png_bytef **)0, 1);
png_write_rows(&write_ptr, &row_buf, 1); png_write_rows(&write_ptr, (png_bytef **)&row_buf, 1);
} }
} }
@ -134,7 +144,7 @@ int main()
if (!fpin) if (!fpin)
{ {
fprintf(STDERR, "could not find file %s\n", inname); fprintf(STDERR, "could not find file %s\n", inname);
return -1; return 1;
} }
fpout = fopen(outname, "rb"); fpout = fopen(outname, "rb");
@ -142,7 +152,7 @@ int main()
{ {
fprintf(STDERR, "could not find file %s\n", outname); fprintf(STDERR, "could not find file %s\n", outname);
fclose(fpin); fclose(fpin);
return -1; return 1;
} }
while (1) while (1)
@ -157,7 +167,7 @@ int main()
fprintf(STDERR, "files are of a different size\n"); fprintf(STDERR, "files are of a different size\n");
fclose(fpin); fclose(fpin);
fclose(fpout); fclose(fpout);
return -1; return 1;
} }
if (!num_in) if (!num_in)
@ -168,7 +178,7 @@ int main()
fprintf(STDERR, "files are different\n"); fprintf(STDERR, "files are different\n");
fclose(fpin); fclose(fpin);
fclose(fpout); fclose(fpout);
return -1; return 1;
} }
} }
@ -178,3 +188,4 @@ int main()
return 0; return 0;
} }

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pngtest.png
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15
pngtodo.txt
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@ -1,7 +1,13 @@
pngtodo.txt - list of things to do for libpng pngtodo.txt - list of things to do for libpng
allow user to #define out unused transformations for 0.9
medium memory model support medium memory model
improved dithering?
for 1.1
push reader
for 1.1 or later
overlaying one image on top of another overlaying one image on top of another
optional palette creation optional palette creation
histogram creation histogram creation
@ -9,14 +15,13 @@ pngtodo.txt - list of things to do for libpng
cHRM transformation cHRM transformation
support for other chunks being defined (sCAl, the gIF series, support for other chunks being defined (sCAl, the gIF series,
and others that people come up with). and others that people come up with).
push reader
pull writer pull writer
better dithering better dithering
keep up with public chunks keep up with public chunks
other compression libraries other compression libraries
more exotic interlace handling more exotic interlace handling
better filtering better filtering (counting huffman bits? filter type inertia?)
C++ wrapper C++ wrapper
other languages other languages (pascal, for one)
comments of > 64K comments of > 64K

63
pngtrans.c
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@ -2,22 +2,25 @@
/* pngtrans.c - transforms the data in a row /* pngtrans.c - transforms the data in a row
routines used by both readers and writers routines used by both readers and writers
libpng 1.0 beta 1 - version 0.71 libpng 1.0 beta 2 - version 0.81
For conditions of distribution and use, see copyright notice in png.h For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc. Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
June 26, 1995 August 24, 1995
*/ */
#define PNG_INTERNAL #define PNG_INTERNAL
#include "png.h" #include "png.h"
#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
/* turn on bgr to rgb mapping */ /* turn on bgr to rgb mapping */
void void
png_set_bgr(png_struct *png_ptr) png_set_bgr(png_struct *png_ptr)
{ {
png_ptr->transformations |= PNG_BGR; png_ptr->transformations |= PNG_BGR;
} }
#endif
#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
/* turn on 16 bit byte swapping */ /* turn on 16 bit byte swapping */
void void
png_set_swap(png_struct *png_ptr) png_set_swap(png_struct *png_ptr)
@ -25,7 +28,9 @@ png_set_swap(png_struct *png_ptr)
if (png_ptr->bit_depth == 16) if (png_ptr->bit_depth == 16)
png_ptr->transformations |= PNG_SWAP_BYTES; png_ptr->transformations |= PNG_SWAP_BYTES;
} }
#endif
#if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
/* turn on pixel packing */ /* turn on pixel packing */
void void
png_set_packing(png_struct *png_ptr) png_set_packing(png_struct *png_ptr)
@ -36,14 +41,18 @@ png_set_packing(png_struct *png_ptr)
png_ptr->usr_bit_depth = 8; png_ptr->usr_bit_depth = 8;
} }
} }
#endif
#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
void void
png_set_shift(png_struct *png_ptr, png_color_8 *true_bits) png_set_shift(png_struct *png_ptr, png_color_8 *true_bits)
{ {
png_ptr->transformations |= PNG_SHIFT; png_ptr->transformations |= PNG_SHIFT;
png_ptr->shift = *true_bits; png_ptr->shift = *true_bits;
} }
#endif
#if defined(PNG_READ_INTERLACING_SUPPORTED) || defined(PNG_WRITE_INTERLACING_SUPPORTED)
int int
png_set_interlace_handling(png_struct *png_ptr) png_set_interlace_handling(png_struct *png_ptr)
{ {
@ -55,25 +64,35 @@ png_set_interlace_handling(png_struct *png_ptr)
return 1; return 1;
} }
#endif
#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
void void
png_set_rgbx(png_struct *png_ptr) png_set_filler(png_struct *png_ptr, int filler, int filler_loc)
{ {
png_ptr->transformations |= PNG_RGBA; png_ptr->transformations |= PNG_FILLER;
png_ptr->filler = (png_byte)filler;
png_ptr->filler_loc = (png_byte)filler_loc;
if (png_ptr->color_type == PNG_COLOR_TYPE_RGB && if (png_ptr->color_type == PNG_COLOR_TYPE_RGB &&
png_ptr->bit_depth == 8) png_ptr->bit_depth == 8)
png_ptr->usr_channels = 4; png_ptr->usr_channels = 4;
} }
/* old functions kept around for compatability purposes */
void
png_set_rgbx(png_struct *png_ptr)
{
png_set_filler(png_ptr, 0xff, PNG_FILLER_AFTER);
}
void void
png_set_xrgb(png_struct *png_ptr) png_set_xrgb(png_struct *png_ptr)
{ {
png_ptr->transformations |= PNG_XRGB; png_set_filler(png_ptr, 0xff, PNG_FILLER_BEFORE);
if (png_ptr->color_type == PNG_COLOR_TYPE_RGB &&
png_ptr->bit_depth == 8)
png_ptr->usr_channels = 4;
} }
#endif
#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
void void
png_set_invert_mono(png_struct *png_ptr) png_set_invert_mono(png_struct *png_ptr)
{ {
@ -82,12 +101,12 @@ png_set_invert_mono(png_struct *png_ptr)
/* invert monocrome grayscale data */ /* invert monocrome grayscale data */
void void
png_do_invert(png_row_info *row_info, png_byte *row) png_do_invert(png_row_info *row_info, png_bytef *row)
{ {
if (row && row_info && row_info->bit_depth == 1 && if (row && row_info && row_info->bit_depth == 1 &&
row_info->color_type == PNG_COLOR_TYPE_GRAY) row_info->color_type == PNG_COLOR_TYPE_GRAY)
{ {
png_byte *rp; png_bytef *rp;
png_uint_32 i; png_uint_32 i;
for (i = 0, rp = row; for (i = 0, rp = row;
@ -98,14 +117,17 @@ png_do_invert(png_row_info *row_info, png_byte *row)
} }
} }
} }
#endif
#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
/* swaps byte order on 16 bit depth images */ /* swaps byte order on 16 bit depth images */
void void
png_do_swap(png_row_info *row_info, png_byte *row) png_do_swap(png_row_info *row_info, png_bytef *row)
{ {
if (row && row_info && row_info->bit_depth == 16) if (row && row_info && row_info->bit_depth == 16)
{ {
png_byte *rp, t; png_bytef *rp;
png_byte t;
png_uint_32 i; png_uint_32 i;
for (i = 0, rp = row; for (i = 0, rp = row;
@ -118,16 +140,19 @@ png_do_swap(png_row_info *row_info, png_byte *row)
} }
} }
} }
#endif
#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
/* swaps red and blue */ /* swaps red and blue */
void void
png_do_bgr(png_row_info *row_info, png_byte *row) png_do_bgr(png_row_info *row_info, png_bytef *row)
{ {
if (row && row_info && (row_info->color_type & 2)) if (row && row_info && (row_info->color_type & 2))
{ {
if (row_info->color_type == 2 && row_info->bit_depth == 8) if (row_info->color_type == 2 && row_info->bit_depth == 8)
{ {
png_byte *rp, t; png_bytef *rp;
png_byte t;
png_uint_32 i; png_uint_32 i;
for (i = 0, rp = row; for (i = 0, rp = row;
@ -141,7 +166,8 @@ png_do_bgr(png_row_info *row_info, png_byte *row)
} }
else if (row_info->color_type == 6 && row_info->bit_depth == 8) else if (row_info->color_type == 6 && row_info->bit_depth == 8)
{ {
png_byte *rp, t; png_bytef *rp;
png_byte t;
png_uint_32 i; png_uint_32 i;
for (i = 0, rp = row; for (i = 0, rp = row;
@ -155,7 +181,8 @@ png_do_bgr(png_row_info *row_info, png_byte *row)
} }
else if (row_info->color_type == 2 && row_info->bit_depth == 16) else if (row_info->color_type == 2 && row_info->bit_depth == 16)
{ {
png_byte *rp, t[2]; png_bytef *rp;
png_byte t[2];
png_uint_32 i; png_uint_32 i;
for (i = 0, rp = row; for (i = 0, rp = row;
@ -172,7 +199,8 @@ png_do_bgr(png_row_info *row_info, png_byte *row)
} }
else if (row_info->color_type == 6 && row_info->bit_depth == 16) else if (row_info->color_type == 6 && row_info->bit_depth == 16)
{ {
png_byte *rp, t[2]; png_bytef *rp;
png_byte t[2];
png_uint_32 i; png_uint_32 i;
for (i = 0, rp = row; for (i = 0, rp = row;
@ -189,4 +217,5 @@ png_do_bgr(png_row_info *row_info, png_byte *row)
} }
} }
} }
#endif

140
pngwrite.c
View File

@ -1,10 +1,10 @@
/* pngwrite.c - general routines to write a png file /* pngwrite.c - general routines to write a png file
libpng 1.0 beta 1 - version 0.71 libpng 1.0 beta 2 - version 0.81
For conditions of distribution and use, see copyright notice in png.h For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc. Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
June 26, 1995 August 24, 1995
*/ */
/* get internal access to png.h */ /* get internal access to png.h */
@ -30,34 +30,53 @@ png_write_info(png_struct *png_ptr, png_info *info)
info->interlace_type); info->interlace_type);
/* the rest of these check to see if the valid field has the appropriate /* the rest of these check to see if the valid field has the appropriate
flag set, and if it does, writes the chunk. */ flag set, and if it does, writes the chunk. */
#if defined(PNG_WRITE_gAMA_SUPPORTED)
if (info->valid & PNG_INFO_gAMA) if (info->valid & PNG_INFO_gAMA)
png_write_gAMA(png_ptr, info->gamma); png_write_gAMA(png_ptr, info->gamma);
#endif
#if defined(PNG_WRITE_sBIT_SUPPORTED)
if (info->valid & PNG_INFO_sBIT) if (info->valid & PNG_INFO_sBIT)
png_write_sBIT(png_ptr, &(info->sig_bit), info->color_type); png_write_sBIT(png_ptr, &(info->sig_bit), info->color_type);
#endif
#if defined(PNG_WRITE_cHRM_SUPPORTED)
if (info->valid & PNG_INFO_cHRM) if (info->valid & PNG_INFO_cHRM)
png_write_cHRM(png_ptr, png_write_cHRM(png_ptr,
info->x_white, info->y_white, info->x_white, info->y_white,
info->x_red, info->y_red, info->x_red, info->y_red,
info->x_green, info->y_green, info->x_green, info->y_green,
info->x_blue, info->y_blue); info->x_blue, info->y_blue);
#endif
if (info->valid & PNG_INFO_PLTE) if (info->valid & PNG_INFO_PLTE)
png_write_PLTE(png_ptr, info->palette, info->num_palette); png_write_PLTE(png_ptr, info->palette, info->num_palette);
#if defined(PNG_WRITE_tRNS_SUPPORTED)
if (info->valid & PNG_INFO_tRNS) if (info->valid & PNG_INFO_tRNS)
png_write_tRNS(png_ptr, info->trans, &(info->trans_values), png_write_tRNS(png_ptr, info->trans, &(info->trans_values),
info->num_trans, info->color_type); info->num_trans, info->color_type);
#endif
#if defined(PNG_WRITE_bKGD_SUPPORTED)
if (info->valid & PNG_INFO_bKGD) if (info->valid & PNG_INFO_bKGD)
png_write_bKGD(png_ptr, &(info->background), info->color_type); png_write_bKGD(png_ptr, &(info->background), info->color_type);
#endif
#if defined(PNG_WRITE_hIST_SUPPORTED)
if (info->valid & PNG_INFO_hIST) if (info->valid & PNG_INFO_hIST)
png_write_hIST(png_ptr, info->hist, info->num_palette); png_write_hIST(png_ptr, info->hist, info->num_palette);
#endif
#if defined(PNG_WRITE_pHYs_SUPPORTED)
if (info->valid & PNG_INFO_pHYs) if (info->valid & PNG_INFO_pHYs)
png_write_pHYs(png_ptr, info->x_pixels_per_unit, png_write_pHYs(png_ptr, info->x_pixels_per_unit,
info->y_pixels_per_unit, info->phys_unit_type); info->y_pixels_per_unit, info->phys_unit_type);
#endif
#if defined(PNG_WRITE_oFFs_SUPPORTED)
if (info->valid & PNG_INFO_oFFs) if (info->valid & PNG_INFO_oFFs)
png_write_oFFs(png_ptr, info->x_offset, info->y_offset, png_write_oFFs(png_ptr, info->x_offset, info->y_offset,
info->offset_unit_type); info->offset_unit_type);
#endif
#if defined(PNG_WRITE_tIME_SUPPORTED)
if (info->valid & PNG_INFO_tIME) if (info->valid & PNG_INFO_tIME)
png_write_tIME(png_ptr, &(info->mod_time)); png_write_tIME(png_ptr, &(info->mod_time));
/* Check to see if we need to write text chunks */ /* Check to see if we need to write text chunks */
#endif
#if defined(PNG_WRITE_tEXt_SUPPORTED) || defined(PNG_WRITE_zTXt_SUPPORTED)
if (info->num_text) if (info->num_text)
{ {
int i; /* local counter */ int i; /* local counter */
@ -68,19 +87,24 @@ png_write_info(png_struct *png_ptr, png_info *info)
/* if chunk is compressed */ /* if chunk is compressed */
if (info->text[i].compression >= 0) if (info->text[i].compression >= 0)
{ {
#if defined(PNG_WRITE_zTXt_SUPPORTED)
/* write compressed chunk */ /* write compressed chunk */
png_write_zTXt(png_ptr, info->text[i].key, png_write_zTXt(png_ptr, info->text[i].key,
info->text[i].text, info->text[i].text_length, info->text[i].text, info->text[i].text_length,
info->text[i].compression); info->text[i].compression);
#endif
} }
else else
{ {
#if defined(PNG_WRITE_tEXt_SUPPORTED)
/* write uncompressed chunk */ /* write uncompressed chunk */
png_write_tEXt(png_ptr, info->text[i].key, png_write_tEXt(png_ptr, info->text[i].key,
info->text[i].text, info->text[i].text_length); info->text[i].text, info->text[i].text_length);
#endif
} }
} }
} }
#endif
} }
/* writes the end of the png file. If you don't want to write comments or /* writes the end of the png file. If you don't want to write comments or
@ -93,9 +117,12 @@ png_write_end(png_struct *png_ptr, png_info *info)
/* see if user wants us to write information chunks */ /* see if user wants us to write information chunks */
if (info) if (info)
{ {
#if defined(PNG_WRITE_tIME_SUPPORTED)
/* check to see if user has supplied a time chunk */ /* check to see if user has supplied a time chunk */
if (info->valid & PNG_INFO_tIME) if (info->valid & PNG_INFO_tIME)
png_write_tIME(png_ptr, &(info->mod_time)); png_write_tIME(png_ptr, &(info->mod_time));
#endif
#if defined(PNG_WRITE_tEXt_SUPPORTED) || defined(PNG_WRITE_zTXt_SUPPORTED)
/* check to see if we need to write comment chunks */ /* check to see if we need to write comment chunks */
if (info->num_text) if (info->num_text)
{ {
@ -107,32 +134,30 @@ png_write_end(png_struct *png_ptr, png_info *info)
/* check to see if comment is to be compressed */ /* check to see if comment is to be compressed */
if (info->text[i].compression >= 0) if (info->text[i].compression >= 0)
{ {
#if defined(PNG_WRITE_zTXt_SUPPORTED)
/* write compressed chunk */ /* write compressed chunk */
png_write_zTXt(png_ptr, info->text[i].key, png_write_zTXt(png_ptr, info->text[i].key,
info->text[i].text, info->text[i].text_length, info->text[i].text, info->text[i].text_length,
info->text[i].compression); info->text[i].compression);
#endif
} }
else else
{ {
#if defined(PNG_WRITE_tEXt_SUPPORTED)
/* write uncompressed chunk */ /* write uncompressed chunk */
png_write_tEXt(png_ptr, info->text[i].key, png_write_tEXt(png_ptr, info->text[i].key,
info->text[i].text, info->text[i].text_length); info->text[i].text, info->text[i].text_length);
#endif
} }
} }
} }
#endif
} }
/* write end of png file */ /* write end of png file */
png_write_IEND(png_ptr); png_write_IEND(png_ptr);
} }
/* initialize the info structure */ #if defined(PNG_WRITE_tIME_SUPPORTED)
void
png_info_init(png_info *info)
{
/* set everything to 0 */
memset(info, 0, sizeof (png_info));
}
void void
png_convert_from_struct_tm(png_time *ptime, struct tm *ttime) png_convert_from_struct_tm(png_time *ptime, struct tm *ttime)
{ {
@ -152,6 +177,7 @@ png_convert_from_time_t(png_time *ptime, time_t ttime)
tbuf = gmtime(&ttime); tbuf = gmtime(&ttime);
png_convert_from_struct_tm(ptime, tbuf); png_convert_from_struct_tm(ptime, tbuf);
} }
#endif
/* initialize png structure, and allocate any memory needed */ /* initialize png structure, and allocate any memory needed */
void void
@ -160,23 +186,15 @@ png_write_init(png_struct *png_ptr)
jmp_buf tmp_jmp; /* to save current jump buffer */ jmp_buf tmp_jmp; /* to save current jump buffer */
/* save jump buffer */ /* save jump buffer */
memcpy(tmp_jmp, png_ptr->jmpbuf, sizeof (jmp_buf)); png_memcpy(tmp_jmp, png_ptr->jmpbuf, sizeof (jmp_buf));
/* reset all variables to 0 */ /* reset all variables to 0 */
memset(png_ptr, 0, sizeof (png_struct)); png_memset(png_ptr, 0, sizeof (png_struct));
/* restore jump buffer */ /* restore jump buffer */
memcpy(png_ptr->jmpbuf, tmp_jmp, sizeof (jmp_buf)); png_memcpy(png_ptr->jmpbuf, tmp_jmp, sizeof (jmp_buf));
/* initialize zbuf - compression buffer */ /* initialize zbuf - compression buffer */
png_ptr->zbuf_size = PNG_ZBUF_SIZE; png_ptr->zbuf_size = PNG_ZBUF_SIZE;
png_ptr->zbuf = png_large_malloc(png_ptr, png_ptr->zbuf_size); png_ptr->zbuf = png_large_malloc(png_ptr, png_ptr->zbuf_size);
/* initialize zlib */
png_ptr->zstream = &(png_ptr->zstream_struct);
png_ptr->zstream->zalloc = png_zalloc;
png_ptr->zstream->zfree = png_zfree;
png_ptr->zstream->opaque = (voidp)png_ptr;
deflateInit(png_ptr->zstream, Z_BEST_COMPRESSION);
png_ptr->zstream->next_out = png_ptr->zbuf;
png_ptr->zstream->avail_out = (uInt)png_ptr->zbuf_size;
} }
/* write a few rows of image data. If the image is interlaced, /* write a few rows of image data. If the image is interlaced,
@ -184,11 +202,11 @@ png_write_init(png_struct *png_ptr)
have called png_set_interlace_handling(), you will have to have called png_set_interlace_handling(), you will have to
"write" the image seven times */ "write" the image seven times */
void void
png_write_rows(png_struct *png_ptr, png_byte **row, png_write_rows(png_struct *png_ptr, png_bytef **row,
png_uint_32 num_rows) png_uint_32 num_rows)
{ {
png_uint_32 i; /* row counter */ png_uint_32 i; /* row counter */
png_byte **rp; /* row pointer */ png_bytef **rp; /* row pointer */
/* loop through the rows */ /* loop through the rows */
for (i = 0, rp = row; i < num_rows; i++, rp++) for (i = 0, rp = row; i < num_rows; i++, rp++)
@ -200,11 +218,11 @@ png_write_rows(png_struct *png_ptr, png_byte **row,
/* write the image. You only need to call this function once, even /* write the image. You only need to call this function once, even
if you are writing an interlaced image. */ if you are writing an interlaced image. */
void void
png_write_image(png_struct *png_ptr, png_byte **image) png_write_image(png_struct *png_ptr, png_bytef **image)
{ {
png_uint_32 i; /* row index */ png_uint_32 i; /* row index */
int pass, num_pass; /* pass variables */ int pass, num_pass; /* pass variables */
png_byte **rp; /* points to current row */ png_bytef **rp; /* points to current row */
/* intialize interlace handling. If image is not interlaced, /* intialize interlace handling. If image is not interlaced,
this will set pass to 1 */ this will set pass to 1 */
@ -222,7 +240,7 @@ png_write_image(png_struct *png_ptr, png_byte **image)
/* write a row of image data */ /* write a row of image data */
void void
png_write_row(png_struct *png_ptr, png_byte *row) png_write_row(png_struct *png_ptr, png_bytef *row)
{ {
/* initialize transformations and other stuff if first time */ /* initialize transformations and other stuff if first time */
if (png_ptr->row_number == 0 && png_ptr->pass == 0) if (png_ptr->row_number == 0 && png_ptr->pass == 0)
@ -230,6 +248,7 @@ png_write_row(png_struct *png_ptr, png_byte *row)
png_write_start_row(png_ptr); png_write_start_row(png_ptr);
} }
#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
/* if interlaced and not interested in row, return */ /* if interlaced and not interested in row, return */
if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE)) if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
{ {
@ -286,6 +305,7 @@ png_write_row(png_struct *png_ptr, png_byte *row)
break; break;
} }
} }
#endif
/* set up row info for transformations */ /* set up row info for transformations */
png_ptr->row_info.color_type = png_ptr->color_type; png_ptr->row_info.color_type = png_ptr->color_type;
@ -298,8 +318,9 @@ png_write_row(png_struct *png_ptr, png_byte *row)
(png_uint_32)png_ptr->row_info.pixel_depth + 7) >> 3); (png_uint_32)png_ptr->row_info.pixel_depth + 7) >> 3);
/* copy users row into buffer, leaving room for filter byte */ /* copy users row into buffer, leaving room for filter byte */
memcpy(png_ptr->row_buf + 1, row, (png_size_t)png_ptr->row_info.rowbytes); png_memcpy(png_ptr->row_buf + 1, row, (png_size_t)png_ptr->row_info.rowbytes);
#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
/* handle interlacing */ /* handle interlacing */
if (png_ptr->interlaced && png_ptr->pass < 6 && if (png_ptr->interlaced && png_ptr->pass < 6 &&
(png_ptr->transformations & PNG_INTERLACE)) (png_ptr->transformations & PNG_INTERLACE))
@ -313,16 +334,17 @@ png_write_row(png_struct *png_ptr, png_byte *row)
return; return;
} }
} }
#endif
/* handle other transformations */ /* handle other transformations */
if (png_ptr->transformations) if (png_ptr->transformations)
png_do_write_transformations(png_ptr); png_do_write_transformations(png_ptr);
/* filter rows that have been proved to help */ /* filter rows that have been proved to help */
if (png_ptr->bit_depth >= 8 && png_ptr->color_type != 3) if (png_ptr->do_filter)
{ {
/* save row to previous row */ /* save row to previous row */
memcpy(png_ptr->save_row, png_ptr->row_buf, png_memcpy(png_ptr->save_row, png_ptr->row_buf,
(png_size_t)png_ptr->row_info.rowbytes + 1); (png_size_t)png_ptr->row_info.rowbytes + 1);
/* filter row */ /* filter row */
@ -331,7 +353,7 @@ png_write_row(png_struct *png_ptr, png_byte *row)
/* trade saved pointer and prev pointer so next row references are correctly */ /* trade saved pointer and prev pointer so next row references are correctly */
{ /* scope limiter */ { /* scope limiter */
png_byte *tptr; png_bytef *tptr;
tptr = png_ptr->prev_row; tptr = png_ptr->prev_row;
png_ptr->prev_row = png_ptr->save_row; png_ptr->prev_row = png_ptr->save_row;
@ -345,17 +367,6 @@ png_write_row(png_struct *png_ptr, png_byte *row)
/* set up the zlib input buffer */ /* set up the zlib input buffer */
png_ptr->zstream->next_in = png_ptr->row_buf; png_ptr->zstream->next_in = png_ptr->row_buf;
png_ptr->zstream->avail_in = (uInt)png_ptr->row_info.rowbytes + 1; png_ptr->zstream->avail_in = (uInt)png_ptr->row_info.rowbytes + 1;
#ifdef zlibinout
/* temp zlib problem */
{
extern FILE *fpzlibin;
fwrite(png_ptr->row_buf, 1, png_ptr->zstream->avail_in, fpzlibin);
}
/* end temp zlib problem */
#endif
/* repeat until we have compressed all the data */ /* repeat until we have compressed all the data */
do do
{ {
@ -401,8 +412,49 @@ png_write_destroy(png_struct *png_ptr)
png_large_free(png_ptr, png_ptr->prev_row); png_large_free(png_ptr, png_ptr->prev_row);
png_large_free(png_ptr, png_ptr->save_row); png_large_free(png_ptr, png_ptr->save_row);
/* reset structure */ /* reset structure */
memcpy(tmp_jmp, png_ptr->jmpbuf, sizeof (jmp_buf)); png_memcpy(tmp_jmp, png_ptr->jmpbuf, sizeof (jmp_buf));
memset(png_ptr, 0, sizeof (png_struct)); png_memset(png_ptr, 0, sizeof (png_struct));
memcpy(png_ptr->jmpbuf, tmp_jmp, sizeof (jmp_buf)); png_memcpy(png_ptr->jmpbuf, tmp_jmp, sizeof (jmp_buf));
}
void
png_set_filtering(png_struct *png_ptr, int filter)
{
png_ptr->do_custom_filter = 1;
png_ptr->do_filter = filter;
}
void
png_set_compression_level(png_struct *png_ptr, int level)
{
png_ptr->zlib_custom_level = 1;
png_ptr->zlib_level = level;
}
void
png_set_compression_mem_level(png_struct *png_ptr, int mem_level)
{
png_ptr->zlib_custom_mem_level = 1;
png_ptr->zlib_mem_level = mem_level;
}
void
png_set_compression_strategy(png_struct *png_ptr, int strategy)
{
png_ptr->zlib_custom_strategy = 1;
png_ptr->zlib_strategy = strategy;
}
void
png_set_compression_window_bits(png_struct *png_ptr, int window_bits)
{
png_ptr->zlib_custom_window_bits = 1;
png_ptr->zlib_window_bits = window_bits;
}
void
png_set_compression_method(png_struct *png_ptr, int method)
{
png_ptr->zlib_custom_method = 1;
png_ptr->zlib_method = method;
} }

72
pngwtran.c
View File

@ -1,10 +1,10 @@
/* pngwtran.c - transforms the data in a row for png writers /* pngwtran.c - transforms the data in a row for png writers
libpng 1.0 beta 1 - version 0.71 libpng 1.0 beta 2 - version 0.81
For conditions of distribution and use, see copyright notice in png.h For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc. Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
June 26, 1995 August 24, 1995
*/ */
#define PNG_INTERNAL #define PNG_INTERNAL
@ -15,29 +15,41 @@
void void
png_do_write_transformations(png_struct *png_ptr) png_do_write_transformations(png_struct *png_ptr)
{ {
#if defined(PNG_WRITE_FILLER_SUPPORTED)
if (png_ptr->transformations & PNG_RGBA) if (png_ptr->transformations & PNG_RGBA)
png_do_write_rgbx(&(png_ptr->row_info), png_ptr->row_buf + 1); png_do_write_filler(&(png_ptr->row_info), png_ptr->row_buf + 1,
if (png_ptr->transformations & PNG_XRGB) png_ptr->filler_loc);
png_do_write_xrgb(&(png_ptr->row_info), png_ptr->row_buf + 1); #endif
#if defined(PNG_WRITE_PACK_SUPPORTED)
if (png_ptr->transformations & PNG_PACK) if (png_ptr->transformations & PNG_PACK)
png_do_pack(&(png_ptr->row_info), png_ptr->row_buf + 1, png_do_pack(&(png_ptr->row_info), png_ptr->row_buf + 1,
png_ptr->bit_depth); png_ptr->bit_depth);
#endif
#if defined(PNG_WRITE_SHIFT_SUPPORTED)
if (png_ptr->transformations & PNG_SHIFT) if (png_ptr->transformations & PNG_SHIFT)
png_do_shift(&(png_ptr->row_info), png_ptr->row_buf + 1, png_do_shift(&(png_ptr->row_info), png_ptr->row_buf + 1,
&(png_ptr->shift)); &(png_ptr->shift));
#endif
#if defined(PNG_WRITE_SWAP_SUPPORTED)
if (png_ptr->transformations & PNG_SWAP_BYTES) if (png_ptr->transformations & PNG_SWAP_BYTES)
png_do_swap(&(png_ptr->row_info), png_ptr->row_buf + 1); png_do_swap(&(png_ptr->row_info), png_ptr->row_buf + 1);
#endif
#if defined(PNG_WRITE_BGR_SUPPORTED)
if (png_ptr->transformations & PNG_BGR) if (png_ptr->transformations & PNG_BGR)
png_do_bgr(&(png_ptr->row_info), png_ptr->row_buf + 1); png_do_bgr(&(png_ptr->row_info), png_ptr->row_buf + 1);
#endif
#if defined(PNG_WRITE_INVERT_SUPPORTED)
if (png_ptr->transformations & PNG_INVERT_MONO) if (png_ptr->transformations & PNG_INVERT_MONO)
png_do_invert(&(png_ptr->row_info), png_ptr->row_buf + 1); png_do_invert(&(png_ptr->row_info), png_ptr->row_buf + 1);
#endif
} }
#if defined(PNG_WRITE_PACK_SUPPORTED)
/* pack pixels into bytes. Pass the true bit depth in bit_depth. The /* pack pixels into bytes. Pass the true bit depth in bit_depth. The
row_info bit depth should be 8 (one pixel per byte). The channels row_info bit depth should be 8 (one pixel per byte). The channels
should be 1 (this only happens on grayscale and paletted images) */ should be 1 (this only happens on grayscale and paletted images) */
void void
png_do_pack(png_row_info *row_info, png_byte *row, png_byte bit_depth) png_do_pack(png_row_info *row_info, png_bytef *row, png_byte bit_depth)
{ {
if (row_info && row && row_info->bit_depth == 8 && if (row_info && row && row_info->bit_depth == 8 &&
row_info->channels == 1) row_info->channels == 1)
@ -46,8 +58,8 @@ png_do_pack(png_row_info *row_info, png_byte *row, png_byte bit_depth)
{ {
case 1: case 1:
{ {
png_byte *sp; png_bytef *sp;
png_byte *dp; png_bytef *dp;
int mask; int mask;
png_int_32 i; png_int_32 i;
int v; int v;
@ -77,8 +89,8 @@ png_do_pack(png_row_info *row_info, png_byte *row, png_byte bit_depth)
} }
case 2: case 2:
{ {
png_byte *sp; png_bytef *sp;
png_byte *dp; png_bytef *dp;
int shift; int shift;
png_int_32 i; png_int_32 i;
int v; int v;
@ -109,8 +121,8 @@ png_do_pack(png_row_info *row_info, png_byte *row, png_byte bit_depth)
} }
case 4: case 4:
{ {
png_byte *sp; png_bytef *sp;
png_byte *dp; png_bytef *dp;
int shift; int shift;
png_int_32 i; png_int_32 i;
int v; int v;
@ -148,7 +160,9 @@ png_do_pack(png_row_info *row_info, png_byte *row, png_byte bit_depth)
((row_info->width * row_info->pixel_depth + 7) >> 3); ((row_info->width * row_info->pixel_depth + 7) >> 3);
} }
} }
#endif
#if defined(PNG_WRITE_SHIFT_SUPPORTED)
/* shift pixel values to take advantage of whole range. Pass the /* shift pixel values to take advantage of whole range. Pass the
true number of bits in bit_depth. The row should be packed true number of bits in bit_depth. The row should be packed
according to row_info->bit_depth. Thus, if you had a row of according to row_info->bit_depth. Thus, if you had a row of
@ -156,7 +170,7 @@ png_do_pack(png_row_info *row_info, png_byte *row, png_byte bit_depth)
would pass 3 as bit_depth, and this routine would translate the would pass 3 as bit_depth, and this routine would translate the
data to 0 to 15. */ data to 0 to 15. */
void void
png_do_shift(png_row_info *row_info, png_byte *row, png_color_8 *bit_depth) png_do_shift(png_row_info *row_info, png_bytef *row, png_color_8 *bit_depth)
{ {
if (row && row_info && if (row && row_info &&
row_info->color_type != PNG_COLOR_TYPE_PALETTE) row_info->color_type != PNG_COLOR_TYPE_PALETTE)
@ -193,7 +207,7 @@ png_do_shift(png_row_info *row_info, png_byte *row, png_color_8 *bit_depth)
/* with low row dephts, could only be grayscale, so one channel */ /* with low row dephts, could only be grayscale, so one channel */
if (row_info->bit_depth < 8) if (row_info->bit_depth < 8)
{ {
png_byte *bp; png_bytef *bp;
png_uint_32 i; png_uint_32 i;
int j; int j;
png_byte mask; png_byte mask;
@ -222,7 +236,7 @@ png_do_shift(png_row_info *row_info, png_byte *row, png_color_8 *bit_depth)
} }
else if (row_info->bit_depth == 8) else if (row_info->bit_depth == 8)
{ {
png_byte *bp; png_bytef *bp;
png_uint_32 i; png_uint_32 i;
int j; int j;
@ -248,7 +262,7 @@ png_do_shift(png_row_info *row_info, png_byte *row, png_color_8 *bit_depth)
} }
else else
{ {
png_byte *bp; png_bytef *bp;
png_uint_32 i; png_uint_32 i;
int j; int j;
@ -278,15 +292,20 @@ png_do_shift(png_row_info *row_info, png_byte *row, png_color_8 *bit_depth)
} }
} }
} }
#endif
/* remove filler byte after rgb */ #ifdef PNG_WRITE_FILLER_SUPPORTED
/* remove filler byte */
void void
png_do_write_rgbx(png_row_info *row_info, png_byte *row) png_do_write_filler(png_row_info *row_info, png_bytef *row,
png_byte filler_loc)
{ {
if (row && row_info && row_info->color_type == PNG_COLOR_TYPE_RGB && if (row && row_info && row_info->color_type == PNG_COLOR_TYPE_RGB &&
row_info->bit_depth == 8) row_info->bit_depth == 8)
{ {
png_byte *sp, *dp; if (filler_loc == PNG_FILLER_AFTER)
{
png_bytef *sp, *dp;
png_uint_32 i; png_uint_32 i;
for (i = 1, sp = row + 4, dp = row + 3; for (i = 1, sp = row + 4, dp = row + 3;
@ -302,19 +321,12 @@ png_do_write_rgbx(png_row_info *row_info, png_byte *row)
row_info->pixel_depth = 24; row_info->pixel_depth = 24;
row_info->rowbytes = row_info->width * 3; row_info->rowbytes = row_info->width * 3;
} }
} else
/* remove filler byte before rgb */
void
png_do_write_xrgb(png_row_info *row_info, png_byte *row)
{
if (row && row_info && row_info->color_type == PNG_COLOR_TYPE_RGB &&
row_info->bit_depth == 8)
{ {
png_byte *sp, *dp; png_bytef *sp, *dp;
png_uint_32 i; png_uint_32 i;
for (i = 0, sp = row, dp = row; for (i = 1, sp = row + 4, dp = row + 3;
i < row_info->width; i < row_info->width;
i++) i++)
{ {
@ -327,5 +339,7 @@ png_do_write_xrgb(png_row_info *row_info, png_byte *row)
row_info->pixel_depth = 24; row_info->pixel_depth = 24;
row_info->rowbytes = row_info->width * 3; row_info->rowbytes = row_info->width * 3;
} }
}
} }
#endif

317
pngwutil.c
View File

@ -1,10 +1,10 @@
/* pngwutil.c - utilities to write a png file /* pngwutil.c - utilities to write a png file
libpng 1.0 beta 1 - version 0.71 libpng 1.0 beta 2 - version 0.81
For conditions of distribution and use, see copyright notice in png.h For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc. Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
June 26, 1995 August 24, 1995
*/ */
#define PNG_INTERNAL #define PNG_INTERNAL
#include "png.h" #include "png.h"
@ -63,7 +63,7 @@ png_write_uint_16(png_struct *png_ptr, png_uint_16 i)
functions instead. */ functions instead. */
void void
png_write_chunk(png_struct *png_ptr, png_byte *type, png_write_chunk(png_struct *png_ptr, png_byte *type,
png_byte *data, png_uint_32 length) png_bytef *data, png_uint_32 length)
{ {
/* write length */ /* write length */
png_write_uint_32(png_ptr, length); png_write_uint_32(png_ptr, length);
@ -103,7 +103,7 @@ png_write_chunk_start(png_struct *png_ptr, png_byte *type,
sum of the lengths from these calls *must* add up to the total_length sum of the lengths from these calls *must* add up to the total_length
given to png_write_chunk_start() */ given to png_write_chunk_start() */
void void
png_write_chunk_data(png_struct *png_ptr, png_byte *data, png_uint_32 length) png_write_chunk_data(png_struct *png_ptr, png_bytef *data, png_uint_32 length)
{ {
/* write the data, and run the crc over it */ /* write the data, and run the crc over it */
if (length) if (length)
@ -179,6 +179,42 @@ png_write_IHDR(png_struct *png_ptr, png_uint_32 width, png_uint_32 height,
/* write the chunk */ /* write the chunk */
png_write_chunk(png_ptr, png_IHDR, buf, (png_uint_32)13); png_write_chunk(png_ptr, png_IHDR, buf, (png_uint_32)13);
/* initialize zlib with png info */
png_ptr->zstream = &(png_ptr->zstream_struct);
png_ptr->zstream->zalloc = png_zalloc;
png_ptr->zstream->zfree = png_zfree;
png_ptr->zstream->opaque = (voidp)png_ptr;
if (!png_ptr->do_custom_filter)
{
if (png_ptr->color_type == 3 || png_ptr->bit_depth < 8)
png_ptr->do_filter = 0;
else
png_ptr->do_filter = 1;
}
if (!png_ptr->zlib_custom_strategy)
{
if (png_ptr->do_filter)
png_ptr->zlib_strategy = Z_FILTERED;
else
png_ptr->zlib_strategy = Z_DEFAULT_STRATEGY;
}
if (!png_ptr->zlib_custom_level)
png_ptr->zlib_level = Z_DEFAULT_COMPRESSION;
if (!png_ptr->zlib_custom_mem_level)
png_ptr->zlib_mem_level = 8;
if (!png_ptr->zlib_custom_window_bits)
png_ptr->zlib_window_bits = 15;
if (!png_ptr->zlib_custom_method)
png_ptr->zlib_method = 8;
deflateInit2(png_ptr->zstream, png_ptr->zlib_level,
png_ptr->zlib_method,
png_ptr->zlib_window_bits,
png_ptr->zlib_mem_level,
png_ptr->zlib_strategy);
png_ptr->zstream->next_out = png_ptr->zbuf;
png_ptr->zstream->avail_out = (uInt)png_ptr->zbuf_size;
} }
/* write the palette. We are careful not to trust png_color to be in the /* write the palette. We are careful not to trust png_color to be in the
@ -206,18 +242,8 @@ png_write_PLTE(png_struct *png_ptr, png_color *palette, int number)
/* write an IDAT chunk */ /* write an IDAT chunk */
void void
png_write_IDAT(png_struct *png_ptr, png_byte *data, png_uint_32 length) png_write_IDAT(png_struct *png_ptr, png_bytef *data, png_uint_32 length)
{ {
#ifdef zlibinout
/* temp zlib problem */
{
extern FILE *fpzlibout;
fwrite(data, 1, length, fpzlibout);
}
/* end temp zlib problem */
#endif
png_write_chunk(png_ptr, png_IDAT, data, length); png_write_chunk(png_ptr, png_IDAT, data, length);
} }
@ -228,6 +254,7 @@ png_write_IEND(png_struct *png_ptr)
png_write_chunk(png_ptr, png_IEND, NULL, (png_uint_32)0); png_write_chunk(png_ptr, png_IEND, NULL, (png_uint_32)0);
} }
#if defined(PNG_WRITE_gAMA_SUPPORTED)
/* write a gAMA chunk */ /* write a gAMA chunk */
void void
png_write_gAMA(png_struct *png_ptr, float gamma) png_write_gAMA(png_struct *png_ptr, float gamma)
@ -240,7 +267,9 @@ png_write_gAMA(png_struct *png_ptr, float gamma)
png_save_uint_32(buf, igamma); png_save_uint_32(buf, igamma);
png_write_chunk(png_ptr, png_gAMA, buf, (png_uint_32)4); png_write_chunk(png_ptr, png_gAMA, buf, (png_uint_32)4);
} }
#endif
#if defined(PNG_WRITE_sBIT_SUPPORTED)
/* write the sBIT chunk */ /* write the sBIT chunk */
void void
png_write_sBIT(png_struct *png_ptr, png_color_8 *sbit, int color_type) png_write_sBIT(png_struct *png_ptr, png_color_8 *sbit, int color_type)
@ -269,7 +298,9 @@ png_write_sBIT(png_struct *png_ptr, png_color_8 *sbit, int color_type)
png_write_chunk(png_ptr, png_sBIT, buf, (png_uint_32)size); png_write_chunk(png_ptr, png_sBIT, buf, (png_uint_32)size);
} }
#endif
#if defined(PNG_WRITE_cHRM_SUPPORTED)
/* write the cHRM chunk */ /* write the cHRM chunk */
void void
png_write_cHRM(png_struct *png_ptr, float white_x, float white_y, png_write_cHRM(png_struct *png_ptr, float white_x, float white_y,
@ -298,7 +329,9 @@ png_write_cHRM(png_struct *png_ptr, float white_x, float white_y,
png_save_uint_32(buf + 28, itemp); png_save_uint_32(buf + 28, itemp);
png_write_chunk(png_ptr, png_cHRM, buf, (png_uint_32)32); png_write_chunk(png_ptr, png_cHRM, buf, (png_uint_32)32);
} }
#endif
#if defined(PNG_WRITE_tRNS_SUPPORTED)
/* write the tRNS chunk */ /* write the tRNS chunk */
void void
png_write_tRNS(png_struct *png_ptr, png_byte *trans, png_color_16 *tran, png_write_tRNS(png_struct *png_ptr, png_byte *trans, png_color_16 *tran,
@ -326,7 +359,9 @@ png_write_tRNS(png_struct *png_ptr, png_byte *trans, png_color_16 *tran,
png_write_chunk(png_ptr, png_tRNS, buf, (png_uint_32)6); png_write_chunk(png_ptr, png_tRNS, buf, (png_uint_32)6);
} }
} }
#endif
#if defined(PNG_WRITE_bKGD_SUPPORTED)
/* write the background chunk */ /* write the background chunk */
void void
png_write_bKGD(png_struct *png_ptr, png_color_16 *back, int color_type) png_write_bKGD(png_struct *png_ptr, png_color_16 *back, int color_type)
@ -351,7 +386,9 @@ png_write_bKGD(png_struct *png_ptr, png_color_16 *back, int color_type)
png_write_chunk(png_ptr, png_bKGD, buf, (png_uint_32)2); png_write_chunk(png_ptr, png_bKGD, buf, (png_uint_32)2);
} }
} }
#endif
#if defined(PNG_WRITE_hIST_SUPPORTED)
/* write the histogram */ /* write the histogram */
void void
png_write_hIST(png_struct *png_ptr, png_uint_16 *hist, int number) png_write_hIST(png_struct *png_ptr, png_uint_16 *hist, int number)
@ -367,38 +404,42 @@ png_write_hIST(png_struct *png_ptr, png_uint_16 *hist, int number)
} }
png_write_chunk_end(png_ptr); png_write_chunk_end(png_ptr);
} }
#endif
#if defined(PNG_WRITE_tEXt_SUPPORTED)
/* write a tEXt chunk */ /* write a tEXt chunk */
void void
png_write_tEXt(png_struct *png_ptr, char *key, char *text, png_write_tEXt(png_struct *png_ptr, charf *key, charf *text,
png_uint_32 text_len) png_uint_32 text_len)
{ {
int key_len; int key_len;
key_len = strlen(key); key_len = png_strlen(key);
/* make sure we count the 0 after the key */ /* make sure we count the 0 after the key */
png_write_chunk_start(png_ptr, png_tEXt, png_write_chunk_start(png_ptr, png_tEXt,
(png_uint_32)(key_len + text_len + 1)); (png_uint_32)(key_len + text_len + 1));
/* key has an 0 at the end. How nice */ /* key has an 0 at the end. How nice */
png_write_chunk_data(png_ptr, (png_byte *)key, (png_uint_32)(key_len + 1)); png_write_chunk_data(png_ptr, (png_bytef *)key, (png_uint_32)(key_len + 1));
if (text && text_len) if (text && text_len)
png_write_chunk_data(png_ptr, (png_byte *)text, (png_uint_32)text_len); png_write_chunk_data(png_ptr, (png_bytef *)text, (png_uint_32)text_len);
png_write_chunk_end(png_ptr); png_write_chunk_end(png_ptr);
} }
#endif
#if defined(PNG_WRITE_zTXt_SUPPORTED)
/* write a compressed chunk */ /* write a compressed chunk */
void void
png_write_zTXt(png_struct *png_ptr, char *key, char *text, png_write_zTXt(png_struct *png_ptr, charf *key, charf *text,
png_uint_32 text_len, int compression) png_uint_32 text_len, int compression)
{ {
int key_len; int key_len;
char buf[1]; char buf[1];
int i, ret; int i, ret;
char **output_ptr = NULL; /* array of pointers to output */ charf **output_ptr = NULL; /* array of pointers to output */
int num_output_ptr = 0; /* number of output pointers used */ int num_output_ptr = 0; /* number of output pointers used */
int max_output_ptr = 0; /* size of output_ptr */ int max_output_ptr = 0; /* size of output_ptr */
key_len = strlen(key); key_len = png_strlen(key);
/* we can't write the chunk until we find out how much data we have, /* we can't write the chunk until we find out how much data we have,
which means we need to run the compresser first, and save the which means we need to run the compresser first, and save the
@ -408,9 +449,9 @@ png_write_zTXt(png_struct *png_ptr, char *key, char *text,
/* set up the compression buffers */ /* set up the compression buffers */
png_ptr->zstream->avail_in = (uInt)text_len; png_ptr->zstream->avail_in = (uInt)text_len;
png_ptr->zstream->next_in = (Byte *)text; png_ptr->zstream->next_in = (Bytef *)text;
png_ptr->zstream->avail_out = (uInt)png_ptr->zbuf_size; png_ptr->zstream->avail_out = (uInt)png_ptr->zbuf_size;
png_ptr->zstream->next_out = (Byte *)png_ptr->zbuf; png_ptr->zstream->next_out = (Bytef *)png_ptr->zbuf;
/* this is the same compression loop as in png_write_row() */ /* this is the same compression loop as in png_write_row() */
do do
@ -431,10 +472,14 @@ png_write_zTXt(png_struct *png_ptr, char *key, char *text,
/* make sure the output array has room */ /* make sure the output array has room */
if (num_output_ptr >= max_output_ptr) if (num_output_ptr >= max_output_ptr)
{ {
png_uint_32 old_max;
old_max = max_output_ptr;
max_output_ptr = num_output_ptr + 4; max_output_ptr = num_output_ptr + 4;
if (output_ptr) if (output_ptr)
output_ptr = png_realloc(png_ptr, output_ptr, output_ptr = png_realloc(png_ptr, output_ptr,
max_output_ptr * sizeof (char *)); max_output_ptr * sizeof (char *),
old_max * sizeof (char *));
else else
output_ptr = png_malloc(png_ptr, output_ptr = png_malloc(png_ptr,
max_output_ptr * sizeof (char *)); max_output_ptr * sizeof (char *));
@ -443,7 +488,7 @@ png_write_zTXt(png_struct *png_ptr, char *key, char *text,
/* save the data */ /* save the data */
output_ptr[num_output_ptr] = png_large_malloc(png_ptr, output_ptr[num_output_ptr] = png_large_malloc(png_ptr,
png_ptr->zbuf_size); png_ptr->zbuf_size);
memcpy(output_ptr[num_output_ptr], png_ptr->zbuf, png_memcpy(output_ptr[num_output_ptr], png_ptr->zbuf,
(png_size_t)png_ptr->zbuf_size); (png_size_t)png_ptr->zbuf_size);
num_output_ptr++; num_output_ptr++;
@ -474,10 +519,14 @@ png_write_zTXt(png_struct *png_ptr, char *key, char *text,
/* check to make sure our output array has room */ /* check to make sure our output array has room */
if (num_output_ptr >= max_output_ptr) if (num_output_ptr >= max_output_ptr)
{ {
png_uint_32 old_max;
old_max = max_output_ptr;
max_output_ptr = num_output_ptr + 4; max_output_ptr = num_output_ptr + 4;
if (output_ptr) if (output_ptr)
output_ptr = png_realloc(png_ptr, output_ptr, output_ptr = png_realloc(png_ptr, output_ptr,
max_output_ptr * sizeof (char *)); max_output_ptr * sizeof (char *),
old_max * sizeof (char *));
else else
output_ptr = png_malloc(png_ptr, output_ptr = png_malloc(png_ptr,
max_output_ptr * sizeof (char *)); max_output_ptr * sizeof (char *));
@ -486,7 +535,7 @@ png_write_zTXt(png_struct *png_ptr, char *key, char *text,
/* save off the data */ /* save off the data */
output_ptr[num_output_ptr] = png_large_malloc(png_ptr, output_ptr[num_output_ptr] = png_large_malloc(png_ptr,
png_ptr->zbuf_size); png_ptr->zbuf_size);
memcpy(output_ptr[num_output_ptr], png_ptr->zbuf, png_memcpy(output_ptr[num_output_ptr], png_ptr->zbuf,
(png_size_t)png_ptr->zbuf_size); (png_size_t)png_ptr->zbuf_size);
num_output_ptr++; num_output_ptr++;
@ -506,7 +555,7 @@ png_write_zTXt(png_struct *png_ptr, char *key, char *text,
png_write_chunk_start(png_ptr, png_zTXt, png_write_chunk_start(png_ptr, png_zTXt,
(png_uint_32)(key_len + text_len + 2)); (png_uint_32)(key_len + text_len + 2));
/* write key */ /* write key */
png_write_chunk_data(png_ptr, (png_byte *)key, (png_uint_32)(key_len + 1)); png_write_chunk_data(png_ptr, (png_bytef *)key, (png_uint_32)(key_len + 1));
buf[0] = compression; buf[0] = compression;
/* write compression */ /* write compression */
png_write_chunk_data(png_ptr, (png_byte *)buf, (png_uint_32)1); png_write_chunk_data(png_ptr, (png_byte *)buf, (png_uint_32)1);
@ -514,7 +563,7 @@ png_write_zTXt(png_struct *png_ptr, char *key, char *text,
/* write saved output buffers, if any */ /* write saved output buffers, if any */
for (i = 0; i < num_output_ptr; i++) for (i = 0; i < num_output_ptr; i++)
{ {
png_write_chunk_data(png_ptr, (png_byte *)output_ptr[i], png_ptr->zbuf_size); png_write_chunk_data(png_ptr, (png_bytef *)output_ptr[i], png_ptr->zbuf_size);
png_large_free(png_ptr, output_ptr[i]); png_large_free(png_ptr, output_ptr[i]);
} }
if (max_output_ptr) if (max_output_ptr)
@ -527,11 +576,11 @@ png_write_zTXt(png_struct *png_ptr, char *key, char *text,
png_write_chunk_end(png_ptr); png_write_chunk_end(png_ptr);
/* reset zlib for another zTXt or the image data */ /* reset zlib for another zTXt or the image data */
/* deflateReset(png_ptr->zstream); */ deflateReset(png_ptr->zstream);
deflateEnd(png_ptr->zstream);
deflateInit(png_ptr->zstream, -1);
} }
#endif
#if defined(PNG_WRITE_pHYs_SUPPORTED)
/* write the pHYs chunk */ /* write the pHYs chunk */
void void
png_write_pHYs(png_struct *png_ptr, png_uint_32 x_pixels_per_unit, png_write_pHYs(png_struct *png_ptr, png_uint_32 x_pixels_per_unit,
@ -546,7 +595,9 @@ png_write_pHYs(png_struct *png_ptr, png_uint_32 x_pixels_per_unit,
png_write_chunk(png_ptr, png_pHYs, buf, (png_uint_32)9); png_write_chunk(png_ptr, png_pHYs, buf, (png_uint_32)9);
} }
#endif
#if defined(PNG_WRITE_oFFs_SUPPORTED)
/* write the oFFs chunk */ /* write the oFFs chunk */
void void
png_write_oFFs(png_struct *png_ptr, png_uint_32 x_offset, png_write_oFFs(png_struct *png_ptr, png_uint_32 x_offset,
@ -561,9 +612,11 @@ png_write_oFFs(png_struct *png_ptr, png_uint_32 x_offset,
png_write_chunk(png_ptr, png_oFFs, buf, (png_uint_32)9); png_write_chunk(png_ptr, png_oFFs, buf, (png_uint_32)9);
} }
#endif
/* two time chunks are given. This chunk assumes you have a gmtime() #if defined(PNG_WRITE_tIME_SUPPORTED)
function. If you don't have that, use the other tIME function */ /* write the tIME chunk. Use either png_convert_from_struct_tm()
or png_convert_from_time_t(), or fill in the structure yourself */
void void
png_write_tIME(png_struct *png_ptr, png_time *mod_time) png_write_tIME(png_struct *png_ptr, png_time *mod_time)
{ {
@ -578,25 +631,26 @@ png_write_tIME(png_struct *png_ptr, png_time *mod_time)
png_write_chunk(png_ptr, png_tIME, buf, (png_uint_32)7); png_write_chunk(png_ptr, png_tIME, buf, (png_uint_32)7);
} }
#endif
/* initializes the row writing capability of libpng */ /* initializes the row writing capability of libpng */
void void
png_write_start_row(png_struct *png_ptr) png_write_start_row(png_struct *png_ptr)
{ {
/* set up row buffer */ /* set up row buffer */
png_ptr->row_buf = (png_byte *)png_large_malloc(png_ptr, png_ptr->row_buf = (png_bytef *)png_large_malloc(png_ptr,
(((png_uint_32)png_ptr->usr_channels * (((png_uint_32)png_ptr->usr_channels *
(png_uint_32)png_ptr->usr_bit_depth * (png_uint_32)png_ptr->usr_bit_depth *
png_ptr->width) >> 3) + 1); png_ptr->width) >> 3) + 1);
/* set up filtering buffers, if filtering */ /* set up filtering buffers, if filtering */
if (png_ptr->bit_depth >= 8 && png_ptr->color_type != 3) if (png_ptr->do_filter)
{ {
png_ptr->prev_row = (png_byte *)png_large_malloc(png_ptr, png_ptr->prev_row = (png_bytef *)png_large_malloc(png_ptr,
png_ptr->rowbytes + 1); png_ptr->rowbytes + 1);
memset(png_ptr->prev_row, 0, (png_size_t)png_ptr->rowbytes + 1); png_memset(png_ptr->prev_row, 0, (png_size_t)png_ptr->rowbytes + 1);
png_ptr->save_row = (png_byte *)png_large_malloc(png_ptr, png_ptr->save_row = (png_bytef *)png_large_malloc(png_ptr,
png_ptr->rowbytes + 1); png_ptr->rowbytes + 1);
memset(png_ptr->save_row, 0, (png_size_t)png_ptr->rowbytes + 1); png_memset(png_ptr->save_row, 0, (png_size_t)png_ptr->rowbytes + 1);
} }
/* if interlaced, we need to set up width and height of pass */ /* if interlaced, we need to set up width and height of pass */
@ -662,13 +716,15 @@ png_write_finish_row(png_struct *png_ptr)
png_pass_yinc[png_ptr->pass] - 1 - png_pass_yinc[png_ptr->pass] - 1 -
png_pass_ystart[png_ptr->pass]) / png_pass_ystart[png_ptr->pass]) /
png_pass_yinc[png_ptr->pass]; png_pass_yinc[png_ptr->pass];
if (png_ptr->transformations & PNG_INTERLACE)
break;
} while (png_ptr->usr_width == 0 || png_ptr->num_rows == 0); } while (png_ptr->usr_width == 0 || png_ptr->num_rows == 0);
} }
/* reset filter row */ /* reset filter row */
if (png_ptr->prev_row) if (png_ptr->prev_row)
memset(png_ptr->prev_row, 0, (png_size_t)png_ptr->rowbytes + 1); png_memset(png_ptr->prev_row, 0, (png_size_t)png_ptr->rowbytes + 1);
/* if we have more data to get, go get it */ /* if we have more data to get, go get it */
if (png_ptr->pass < 7) if (png_ptr->pass < 7)
return; return;
@ -704,12 +760,10 @@ png_write_finish_row(png_struct *png_ptr)
png_ptr->zstream->avail_out); png_ptr->zstream->avail_out);
} }
/* deflateReset(png_ptr->zstream); */ deflateReset(png_ptr->zstream);
deflateEnd(png_ptr->zstream);
deflateInit(png_ptr->zstream, -1);
} }
#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
/* pick out the correct pixels for the interlace pass. /* pick out the correct pixels for the interlace pass.
The basic idea here is to go through the row with a source The basic idea here is to go through the row with a source
@ -719,7 +773,7 @@ png_write_finish_row(png_struct *png_ptr)
See the default: case for the easiest code to understand. See the default: case for the easiest code to understand.
*/ */
void void
png_do_write_interlace(png_row_info *row_info, png_byte *row, int pass) png_do_write_interlace(png_row_info *row_info, png_bytef *row, int pass)
{ {
/* we don't have to do anything on the last pass (6) */ /* we don't have to do anything on the last pass (6) */
if (row && row_info && pass < 6) if (row && row_info && pass < 6)
@ -729,8 +783,8 @@ png_do_write_interlace(png_row_info *row_info, png_byte *row, int pass)
{ {
case 1: case 1:
{ {
png_byte *sp; png_bytef *sp;
png_byte *dp; png_bytef *dp;
int shift; int shift;
int d; int d;
int value; int value;
@ -763,8 +817,8 @@ png_do_write_interlace(png_row_info *row_info, png_byte *row, int pass)
} }
case 2: case 2:
{ {
png_byte *sp; png_bytef *sp;
png_byte *dp; png_bytef *dp;
int shift; int shift;
int d; int d;
int value; int value;
@ -796,8 +850,8 @@ png_do_write_interlace(png_row_info *row_info, png_byte *row, int pass)
} }
case 4: case 4:
{ {
png_byte *sp; png_bytef *sp;
png_byte *dp; png_bytef *dp;
int shift; int shift;
int d; int d;
int value; int value;
@ -829,8 +883,8 @@ png_do_write_interlace(png_row_info *row_info, png_byte *row, int pass)
} }
default: default:
{ {
png_byte *sp; png_bytef *sp;
png_byte *dp; png_bytef *dp;
png_uint_32 i; png_uint_32 i;
int pixel_bytes; int pixel_bytes;
@ -848,7 +902,7 @@ png_do_write_interlace(png_row_info *row_info, png_byte *row, int pass)
sp = row + (png_size_t)(i * pixel_bytes); sp = row + (png_size_t)(i * pixel_bytes);
/* move the pixel */ /* move the pixel */
if (dp != sp) if (dp != sp)
memcpy(dp, sp, pixel_bytes); png_memcpy(dp, sp, pixel_bytes);
/* next pixel */ /* next pixel */
dp += pixel_bytes; dp += pixel_bytes;
} }
@ -865,17 +919,18 @@ png_do_write_interlace(png_row_info *row_info, png_byte *row, int pass)
} }
} }
#endif
/* this filters the row. Both row and prev_row have space at the /* this filters the row. Both row and prev_row have space at the
first byte for the filter byte. */ first byte for the filter byte. */
void void
png_write_filter_row(png_row_info *row_info, png_byte *row, png_write_filter_row(png_row_info *row_info, png_bytef *row,
png_byte *prev_row) png_bytef *prev_row)
{ {
int minf, bpp; int minf, bpp;
png_uint_32 i, v; png_uint_32 i, v;
png_uint_32 s, mins; png_uint_32 s0, s1, s2, s3, s4, mins;
png_byte *rp, *pp, *cp, *lp; png_bytef *rp, *pp, *cp, *lp;
/* find out how many bytes offset each pixel is */ /* find out how many bytes offset each pixel is */
bpp = (row_info->pixel_depth + 7) / 8; bpp = (row_info->pixel_depth + 7) / 8;
@ -885,95 +940,79 @@ png_write_filter_row(png_row_info *row_info, png_byte *row,
/* the prediction method we use is to find which method provides /* the prediction method we use is to find which method provides
the smallest value when summing the abs of the distances from the smallest value when summing the abs of the distances from
zero using anything >= 128 as negitive numbers. */ zero using anything >= 128 as negitive numbers. */
for (i = 0, s = 0, rp = row + 1; i < row_info->rowbytes; i++, rp++) s0 = s1 = s2 = s3 = s4 = 0;
for (i = 0, rp = row + 1, pp = prev_row + 1, lp = row + 1 - bpp,
cp = prev_row + 1 - bpp;
i < bpp; i++, rp++, pp++, lp++, cp++)
{ {
/* check none filter */
v = *rp; v = *rp;
if (v < 128) if (v < 128)
s += v; s0 += v;
else else
s += 256 - (png_int_32)v; s0 += 256 - v;
}
mins = s;
minf = 0;
/* check sub filter */
for (i = 0, s = 0, rp = row + 1, lp = row + 1 - bpp;
i < row_info->rowbytes; i++, rp++, lp++)
{
if (i >= bpp)
v = (png_byte)(((int)*rp - (int)*lp) & 0xff);
else
v = *rp;
if (v < 128)
s += v;
else
s += 256 - v;
}
if (s < mins)
{
mins = s;
minf = 1;
}
/* check up filter */ /* check up filter */
for (i = 0, s = 0, rp = row + 1, pp = prev_row + 1;
i < row_info->rowbytes; i++, rp++, pp++)
{
v = (png_byte)(((int)*rp - (int)*pp) & 0xff); v = (png_byte)(((int)*rp - (int)*pp) & 0xff);
if (v < 128) if (v < 128)
s += v; s2 += v;
else else
s += 256 - v; s2 += 256 - v;
}
if (s < mins)
{
mins = s;
minf = 2;
}
/* check avg filter */ /* check avg filter */
for (i = 0, s = 0, rp = row + 1, pp = prev_row + 1, lp = row + 1 - bpp;
i < row_info->rowbytes; i++, rp++, pp++, lp++)
{
if (i >= bpp)
v = (png_byte)(((int)*rp - (((int)*pp + (int)*lp) / 2)) & 0xff);
else
v = (png_byte)(((int)*rp - ((int)*pp / 2)) & 0xff); v = (png_byte)(((int)*rp - ((int)*pp / 2)) & 0xff);
if (v < 128) if (v < 128)
s += v; s3 += v;
else else
s += 256 - v; s3 += 256 - v;
} }
if (s < mins) /* some filters are same until we get past bpp */
{ s1 = s0;
mins = s; s4 = s2;
minf = 3;
}
/* check paeth filter */ for (; i < row_info->rowbytes; i++, rp++, pp++, lp++, cp++)
for (i = 0, s = 0, rp = row + 1, pp = prev_row + 1, lp = row + 1 - bpp,
cp = prev_row + 1 - bpp;
i < row_info->rowbytes; i++, rp++, pp++, lp++, cp++)
{ {
int a, b, c, pa, pb, pc, p; int a, b, c, pa, pb, pc, p;
/* check none filter */
v = *rp;
if (v < 128)
s0 += v;
else
s0 += 256 - v;
/* check sub filter */
v = (png_byte)(((int)*rp - (int)*lp) & 0xff);
if (v < 128)
s1 += v;
else
s1 += 256 - v;
/* check up filter */
v = (png_byte)(((int)*rp - (int)*pp) & 0xff);
if (v < 128)
s2 += v;
else
s2 += 256 - v;
/* check avg filter */
v = (png_byte)(((int)*rp - (((int)*pp + (int)*lp) / 2)) & 0xff);
if (v < 128)
s3 += v;
else
s3 += 256 - v;
/* check paeth filter */
b = *pp; b = *pp;
if (i >= bpp)
{
c = *cp; c = *cp;
a = *lp; a = *lp;
}
else
{
a = c = 0;
}
p = a + b - c; p = a + b - c;
pa = abs(p - a); pa = abs(p - a);
pb = abs(p - b); pb = abs(p - b);
@ -989,14 +1028,35 @@ png_write_filter_row(png_row_info *row_info, png_byte *row,
v = (png_byte)(((int)*rp - p) & 0xff); v = (png_byte)(((int)*rp - p) & 0xff);
if (v < 128) if (v < 128)
s += v; s4 += v;
else else
s += 256 - v; s4 += 256 - v;
} }
if (s < mins) mins = s0;
minf = 0;
if (s1 < mins)
{ {
mins = s; mins = s1;
minf = 1;
}
if (s2 < mins)
{
mins = s2;
minf = 2;
}
if (s3 < mins)
{
mins = s3;
minf = 3;
}
if (s4 < mins)
{
mins = s4;
minf = 4; minf = 4;
} }
@ -1078,3 +1138,4 @@ png_write_filter_row(png_row_info *row_info, png_byte *row,
break; break;
} }
} }

57
readme.txt
View File

@ -1,25 +1,40 @@
readme.txt - for libpng 0.71 readme.txt - for libpng 0.8
This is the first beta version of libpng 1.0. By beta, I mean that This is the second beta version of libpng 1.0. I've updated most
all the code for 1.0 is there, and it works on all the machines of the stuff I want to before the final 1.0 version. Remaining
I have running all the tests I have devised. However, there is to do are the medium memory model support (which I'll put in
always one more bug (at least), and I don't have many #define's in as soon as we test this version), better dithering, and any bug
the code (yet) for various platforms that I do not have. Also, I'd fixes and makefile/include additions. I expect a third (and
like to see if I can get the code to compile with as few warnings perhaps final) beta after zlib is officially 1.0.
as possible. Finally, as people use my code, they may have
suggestions for additions that will make pnglib easier to port. I've tried to incorporate all the changes and makefiles everyone
sent me. However, I may of lost some in the flood. If you sent
me a change and I didn't put it in, send it again. Sorry.
Updates from libpng 0.71 include a new transformation,
png_set_filler(), which replaces png_set_rgbx() and
png_set_xrgb(). The old functions will be supported for
awhile, but I'd suggest changing to the new function. Also,
I've added defines in png.h to remove unwanted code from the
compiled library. I've added a new field to png_realloc(), and
fixed various bugs. I've also split up pngstub.c into pngmem.c,
pngio.c, and pngerror.c, in case you need to just change some of
these. I've pulled pngconf.h out of png.h, so you don't have to
remake your changes every new release. I've added a function to
update the png_info structure after you're done setting up your
transformations (png_read_update_info()). The complete list of
changes is in pngchang.txt. Most of you won't be much affected
by any of this. Some of you will want to use the new features.
For a detailed description on using libpng, read libpng.txt. For For a detailed description on using libpng, read libpng.txt. For
usage information and restrictions (what little they are) on libpng, usage information and restrictions (what little they are) on libpng,
see png.h. For a description on using zlib (the compression library see png.h. For a description on using zlib (the compression library
used by libpng) and zlib's restrictions, see zlib.h used by libpng) and zlib's restrictions, see zlib.h
I have included a make file, but you will probably have to modify it I have included a general makefile, but you may have to modify it
for your own needs. I'm using Borland C++, running large memory for your own needs.
model on Windows 3.11, but it should work on almost anything. Support
for medium memory model is planned, but is not in 1.0 (probably in 1.1).
You will need zlib 0.93 to run this. zlib is a compression You will need zlib 0.95 or later to run this. zlib is a compression
library that is useful for more things then just png files. If library that is useful for more things then just png files. If
you need a compression library, check out zlib.h you need a compression library, check out zlib.h
@ -32,10 +47,10 @@ be available at the same place you picked up libpng. If it is
not there, try ftp.uu.net in the /graphics/png directory. not there, try ftp.uu.net in the /graphics/png directory.
This code is currently being archived at ftp.uu.net in the This code is currently being archived at ftp.uu.net in the
/graphics/png directory, and at ftp.group42.com in the /pub/png /graphics/png directory, and at ftp.group42.com (204.94.158.25)
directory, and on CompuServe, Lib 20 (PNG) at GO GRAPHSUP. in the /pub/png directory, and on CompuServe, Lib 20 (PNG SUPPORT)
If you can't find it in any of those places, e-mail me, and I'll at GO GRAPHSUP. If you can't find it in any of those places,
tell you where it is. e-mail me, and I'll help you find it.
If you have any code changes, requests, problems, etc., please e-mail If you have any code changes, requests, problems, etc., please e-mail
them to me. Also, I'd appreciate any make files or project files, them to me. Also, I'd appreciate any make files or project files,
@ -50,7 +65,7 @@ fix. Please mention "libpng" somewhere in the subject line. Thanks.
You can reach me at: You can reach me at:
internet: schalnat&group42.com internet: schalnat@group42.com
CompuServe: 75501,1625 CompuServe: 75501,1625
Please do not send me general questions about PNG. Send them to Please do not send me general questions about PNG. Send them to
@ -63,7 +78,7 @@ and ...". If in doubt, send questions to me. I'll bounce them
to others, if necessary. to others, if necessary.
Please do not send suggestions on how to change PNG. We have Please do not send suggestions on how to change PNG. We have
been discussing PNG for 6 months now, and it is official and been discussing PNG for 9 months now, and it is official and
finished. If you have suggestions for libpng, however, I'll finished. If you have suggestions for libpng, however, I'll
gladly listen. Even if your suggestion is not used for version gladly listen. Even if your suggestion is not used for version
1.0, it may be used later. 1.0, it may be used later.
@ -75,5 +90,5 @@ Good luck, and happy coding.
Internet: schalnat@group42.com Internet: schalnat@group42.com
CompuServe: 75501,1625 CompuServe: 75501,1625
Web: www.group42.com Web: www.group42.com
FTP: ftp.group42.com FTP: ftp.group42.com (204.94.158.25)