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Imported from libpng-0.85.tar

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Guy Schalnat 1995-12-19 03:22:19 -06:00 committed by Glenn Randers-Pehrson
parent 0f71645dfe
commit 6d76471acd
24 changed files with 3505 additions and 2324 deletions
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2
build.bat Normal file
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@ -0,0 +1,2 @@
make -fmakefile.bor -B -DMODEL=m %1 %2 %3 libpng >buildm.out
make -fmakefile.bor -B -DMODEL=l %1 %2 %3 libpng >buildl.out

187
example.c
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@ -40,8 +40,8 @@ int check_png(char *file_name)
void read_png(char *file_name)
{
FILE *fp;
png_struct *png_ptr;
png_info *info_ptr;
png_structp png_ptr;
png_infop info_ptr;
/* open the file */
fp = fopen(file_name, "rb");
@ -79,19 +79,9 @@ void read_png(char *file_name)
png_info_init(info_ptr);
png_read_init(png_ptr);
/* set up the input control for the default input and message functions.
* If we were to replace both the input and message functions we don't
* need to call png_init_io first. */
/* set up the input control */
png_init_io(png_ptr, fp);
/* if you are using replacement read functions, here you would call */
io_ptr = (user_io_struct *)malloc(sizeof(user_io_struct));
png_set_read_fn(png_ptr, (void *)io_ptr, user_read_fn);
/* if you are using replacement message functions, here you would call */
msg_ptr = (user_msg_struct *)malloc(sizeof(user_msg_struct));
png_set_read_fn(png_ptr, (void *)msg_ptr, user_error_fn, user_warning_fn);
/* read the file information */
png_read_info(png_ptr, info_ptr);
@ -117,10 +107,10 @@ void read_png(char *file_name)
if (info_ptr->valid & PNG_INFO_bKGD)
png_set_background(png_ptr, &(info_ptr->background),
PNG_GAMMA_FILE, 1, 1.0);
PNG_BACKGROUND_GAMMA_FILE, 1, 1.0);
else
png_set_background(png_ptr, &my_background,
PNG_GAMMA_SCREEN, 0, 1.0);
PNG_BACKGROUND_GAMMA_SCREEN, 0, 1.0);
/* tell libpng to handle the gamma conversion for you */
if (info_ptr->valid & PNG_INFO_gAMA)
@ -156,7 +146,8 @@ void read_png(char *file_name)
png_set_invert(png_ptr);
/* shift the pixels down to their true bit depth */
if (info_ptr->valid & PNG_INFO_sBIT)
if (info_ptr->valid & PNG_INFO_sBIT &&
info_ptr->bit_depth > info_ptr->sig_bit)
png_set_shift(png_ptr, &(info_ptr->sig_bit));
/* pack pixels into bytes */
@ -193,7 +184,7 @@ void read_png(char *file_name)
of png_info. */
/* the easiest way to read the image */
png_bytef *row_pointers[height];
png_bytep row_pointers[height];
png_read_image(png_ptr, row_pointers);
/* the other way to read images - deal with interlacing */
@ -206,7 +197,7 @@ void read_png(char *file_name)
/* If you are only reading on row at a time, this works */
for (y = 0; y < height; y++)
{
png_bytef *row_pointers = row[y];
png_bytep row_pointers = row[y];
png_read_rows(png_ptr, &row_pointers, NULL, 1);
}
@ -221,13 +212,8 @@ void read_png(char *file_name)
in info_ptr */
png_read_end(png_ptr, info_ptr);
/* if you had allocated any memory structures for custom input or
messaging routines you need to free them before png_read_destroy */
free(png_get_io_ptr(png_ptr));
free(png_get_msg_ptr(png_ptr));
/* clean up after the read, and free any memory allocated */
png_read_destroy(png_ptr, info_ptr, (png_info *)0);
png_read_destroy(png_ptr, info_ptr, (png_infop)0);
/* free the structures */
free(png_ptr);
@ -240,12 +226,129 @@ void read_png(char *file_name)
return;
}
/* progressively read a file */
/* these will normally not be global unless you are only
reading in one image at a time */
png_structp png_ptr;
png_infop info_ptr;
int
initialize_png_reader()
{
png_ptr = malloc(sizeof (png_struct));
if (!png_ptr)
return -1;
info_ptr = malloc(sizeof (png_info));
if (!info_ptr)
{
free(png_ptr);
return -1;
}
if (setjmp(png_ptr->jmpbuf))
{
png_read_destroy(png_ptr, info_ptr, (png_info *)0);
/* free pointers before returning, if necessary */
free(png_ptr);
free(info_ptr);
return -1;
}
png_info_init(info_ptr);
png_read_init(png_ptr);
/* this one's new. You will need to provide all three
function callbacks, even if you aren't using them all.
You can put a void pointer in place of the NULL, and
retrieve the pointer from inside the callbacks using
the function png_get_msg_ptr(png_ptr); */
png_set_progressive_read_fn(png_ptr, NULL,
info_callback, row_callback, end_callback);
return 0;
}
int
process_data(png_bytep buffer, png_uint_32 length)
{
if (setjmp(png_ptr->jmpbuf))
{
png_read_destroy(png_ptr, info_ptr, (png_info *)0);
free(png_ptr);
free(info_ptr);
return -1;
}
/* this one's new also. Simply give it a chunk of data
from the file stream (in order, of course). On Segmented
machines, don't give it any more then 64K. The library
seems to run fine with sizes of 4K, although you can give
it much less if necessary (I assume you can give it chunks
of 1 byte, but I haven't tried less then 256 bytes yet).
When this function returns, you may want to display any
rows that were generated in the row callback. */
png_process_data(png_ptr, info_ptr, buffer, length);
return 0;
}
info_callback(png_structp png_ptr, png_infop info)
{
/* do any setup here, including setting any of the transformations
mentioned in the Reading PNG files section. For now, you _must_
call either png_start_read_image() or png_read_update_info()
after all the transformations are set (even if you don't set
any). You may start getting rows before png_process_data()
returns, so this is your last chance to prepare for that. */
}
row_callback(png_structp png_ptr, png_bytep new_row,
png_uint_32 row_num, int pass)
{
/* this function is called for every row in the image. If the
image is interlacing, and you turned on the interlace handler,
this function will be called for every row in every pass.
Some of these rows will not be changed from the previous pass.
When the row is not changed, the new_row variable will be NULL.
The rows and passes are called in order, so you don't really
need the row_num and pass, but I'm supplying them because it
may make your life easier.
For the non-NULL rows of interlaced images, you must call
png_progressive_combine_row() passing in the row and the
old row. You can call this function for NULL rows (it will
just return) and for non-interlaced images (it just does the
memcpy for you) if it will make the code easier. Thus, you
can just do this for all cases: */
png_progressive_combine_row(png_ptr, old_row, new_row);
/* where old_row is what was displayed for previous rows. Note
that the first pass (pass == 0 really) will completely cover
the old row, so the rows do not have to be initialized. After
the first pass (and only for interlaced images), you will have
to pass the current row, and the function will combine the
old row and the new row. */
}
end_callback(png_structp png_ptr, png_infop info)
{
/* this function is called when the whole image has been read,
including any chunks after the image (up to and including
the IEND). You will usually have the same info chunk as you
had in the header, although some data may have been added
to the comments and time fields.
Most people won't do much here, perhaps setting a flag that
marks the image as finished. */
}
/* write a png file */
void write_png(char *file_name, ... other image information ...)
{
FILE *fp;
png_struct *png_ptr;
png_info *info_ptr;
png_structp png_ptr;
png_infop info_ptr;
/* open the file */
fp = fopen(file_name, "wb");
@ -283,19 +386,9 @@ void write_png(char *file_name, ... other image information ...)
png_info_init(info_ptr);
png_write_init(png_ptr);
/* set up the output control for the default output and message functions.
* If we were to replace both the output and message functions we don't
* need to call png_init_io first. */
/* set up the output control */
png_init_io(png_ptr, fp);
/* if you are using replacement write functions, here you would call */
io_ptr = (user_io_struct *)malloc(sizeof(user_io_struct));
png_set_write_fn(png_ptr, (void *)io_ptr, user_write_fn, user_flush_fn);
/* if you are using replacement message functions, here you would call */
msg_ptr = (user_msg_struct *)malloc(sizeof(user_msg_struct));
png_set_read_fn(png_ptr, (void *)msg_ptr, user_error_fn, user_warning_fn);
/* set the file information here */
info_ptr->width = ;
info_ptr->height = ;
@ -309,16 +402,9 @@ void write_png(char *file_name, ... other image information ...)
/* optional significant bit chunk */
info_ptr->valid |= PNG_INFO_sBIT;
/* if we are dealing with a grayscale image then */
info_ptr->sig_bit.gray = true_bit_depth;
/* otherwise, if we are dealing with a color image then */
info_ptr->sig_bit.red = true_red_bit_depth;
info_ptr->sig_bit.green = true_green_bit_depth;
info_ptr->sig_bit.blue = true_blue_bit_depth;
/* if the image has an alpha channel then */
info_ptr->sig_bit.alpha = true_alpha_bit_depth;
info_ptr->sig_bit = true_bit_depth;
/* optional gamma chunk is a good idea if you can write one */
/* optional gamma chunk */
info_ptr->valid |= PNG_INFO_gAMA;
info_ptr->gamma = gamma;
@ -357,7 +443,7 @@ void write_png(char *file_name, ... other image information ...)
number_passes = 1;
/* the easiest way to write the image */
png_bytef *row_pointers[height];
png_bytep row_pointers[height];
png_write_image(png_ptr, row_pointers);
/* the other way to write the image - deal with interlacing */
@ -370,7 +456,7 @@ void write_png(char *file_name, ... other image information ...)
/* If you are only writing one row at a time, this works */
for (y = 0; y < height; y++)
{
png_bytef *row_pointers = row[y];
png_bytep row_pointers = row[y];
png_write_rows(png_ptr, &row_pointers, 1);
}
}
@ -378,11 +464,6 @@ void write_png(char *file_name, ... other image information ...)
/* write the rest of the file */
png_write_end(png_ptr, info_ptr);
/* if you had allocated any memory structures for custom output or
messaging routines you need to free them before png_write_destroy */
free(png_get_io_ptr(png_ptr));
free(png_get_msg_ptr(png_ptr));
/* clean up after the write, and free any memory allocated */
png_write_destroy(png_ptr);

437
libpng.txt
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@ -1,9 +1,9 @@
libpng.txt - a description on how to use and modify libpng
libpng 1.0 beta 2 - version 0.8
libpng 1.0 beta 2 - version 0.85
For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
August 20, 1995
December 19, 1995
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
@ -45,38 +45,43 @@ The structures:
There are two main structures that are important to libpng, png_struct
and png_info. The first, png_struct, is an internal structure that
will not, for the most part, be used by the general user except as
the first variable passed to every PNG function call.
the first variable passed to every png function call.
The png_info structure is designed to provide information about the
png file. All of it's fields are intended to be examined or modified
by the user. See png.h for a good description of the png_info fields.
And while I'm on the topic, make sure you include the PNG header file:
And while I'm on the topic, make sure you include the png header file:
#include <png.h>
Checking PNG files:
Libpng provides a simple check to see if a file is a PNG file. To
Libpng provides a simple check to see if a file is a png file. To
use it, pass in the first 1 to 8 bytes of the file, and it will return
true or false (1 or 0) depending on whether the bytes could be part
of a PNG file. Of course, the more bytes you pass in, the greater
the accuracy of the prediction.
of a png file. Of course, the more bytes you pass in, the greater
the accuracy of the prediction. If you pass in more then eight bytes,
libpng will only look at the first eight bytes.
fread(header, 1, number, fp);
is_png = png_check_sig(header, number);
Reading PNG files:
This section covers reading png files row by row. Progressive reading
is covered in the next section (although you still need to read this
section, as much of the information is still needed).
The first thing you need to do while reading a PNG file is to allocate
and initialize png_struct and png_info. As these are both large, you
may not want to store these on the stack, unless you have stack space
to spare. Of course, you will want to check if malloc returns NULL.
png_struct *png_ptr = malloc(sizeof (png_struct));
png_structp png_ptr = malloc(sizeof (png_struct));
if (!png_ptr)
return;
png_info *info_ptr = malloc(sizeof (png_info));
png_infop info_ptr = malloc(sizeof (png_info));
if (!info_ptr)
{
free(png_ptr);
@ -95,11 +100,6 @@ much to undo.
return;
}
If you are not using the standard IO functions to do input and
output, and/or not using stderr for your output messages, you will
have the ability to change the functions that libpng uses once
you have allocated the libpng data structures below.
After you have these structures, you will need to set up the
error handling. When libpng encounters an error, it expects to
longjmp back to your routine. Therefore, you will need to call
@ -108,11 +108,10 @@ read the file from different routines, you will need to update
the jmpbuf field every time you enter a new routine that will
call a png_ function. See your documentation of setjmp/longjmp
for your compiler for more information on setjmp/longjmp. See
the discussion on libpng error handling in the Customizing Libpng
section below for more information on how to change the behaviour
of libpng error handling. If an error occurs, and libpng longjmp's
back to your setjmp, you will want to call png_read_destroy() to
free any memory.
the discussion on png error handling in the Customizing Libpng
section below for more information on the png error handling.
If an error occurs, and libpng longjmp's back to your setjmp,
you will want to call png_read_destroy() to free any memory.
if (setjmp(png_ptr->jmpbuf))
{
@ -138,8 +137,9 @@ would be bad.
Now you need to set up the input code. The default for libpng is
to use the C function fread(). If you use this, you will need to
pass a valid FILE * in the function png_init_io(). Be sure that
the file is opened in binary mode. Otherwise, you should see the
section below on Customizing libpng I/O functions.
the file is opened in binary mode. If you wish to handle reading
data in another way, see the discussion on png i/o handling in the
Customizing Libpng section below.
png_init_io(png_ptr, fp);
@ -164,7 +164,7 @@ to read the file. Some of the more important parts of the png_info are:
PNG_INFO_<chunk name> define.
palette and num_palette - the palette for the file
gamma - the gamma the file is written at
sig_bit - the number of significant bits for red, green, blue, grey, alpha
sig_bit and sig_bit_number - the number of significant bits
trans, trans_values, and number_trans - transparency info
hist - histogram of palette
text and num_text - text comments in the file.
@ -179,26 +179,13 @@ suggested keywords, there is no requirement to restrict the use
to these strings. There is a requirement to have at least one
character for a keyword. It is strongly suggested that keywords
be sensible to humans (that's the point), so don't use abbreviations.
Some suggested keywords for tEXT (or zTXt) chunks are:
See the png specification for more details. There is no requirement
to have text after the keyword.
Title Short (one line) title or caption for image
Author Name of image's creator
Copyright Copyright notice (possibly long)
Description Description of image (possibly long)
Software Software used to create the image
Disclaimer Legal disclaimer (possibly long)
Warning Warning of nature of content
Source Device used to create the image
Comment Miscellaneous comment; conversion from GIF comment
Created When the image or source file was created
There is no requirement to have text after the keyword on tEXt chunks.
However, you must have text after the keyword on zTXt chunks, as only
the text gets compressed, and compressing nothing will result in an error.
The maximum length of the keyword is limited to 80 characters. It is
possible to use the same keyword any number of times. The text field
is an array of png_text structures, each holding pointer to a keyword
Keywords are restricted to 80 characters without leading or trailing
spaces, but spaces are allowed within the keyword Nothing
prevents you from duplicating the keyword. The text field is an
array of png_text structures, each holding pointer to a keyword
and a pointer to a text string. Only the text string may be null.
The keyword/text pairs are put into the array in the order that
they are received. However, some or all of the text chunks may be
@ -217,7 +204,7 @@ check to see if it has data that it can do somthing with, you should
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.
This transforms bit depths of less than 8 to 8 bits, changes paletted
This transforms bit depths of less then 8 to 8 bits, changes paletted
images to rgb, and adds an alpha channel if there is transparency
information in a tRNS chunk. This is probably most useful on grayscale
images with bit depths of 2 or 4 and tRNS chunks.
@ -247,17 +234,16 @@ function definition in png.h for more details.
if (info_ptr->valid & PNG_INFO_bKGD)
png_set_backgrond(png_ptr, &(info_ptr->background),
PNG_GAMMA_FILE, 1, 1.0);
PNG_BACKGROUND_GAMMA_FILE, 1, 1.0);
else
png_set_background(png_ptr, &my_background,
PNG_GAMMA_SCREEN, 0, 1.0);
PNG_BACKGROUND_GAMMA_SCREEN, 0, 1.0);
This handles gamma transformations of the data. Pass both the file
gamma and the desired screen gamma. If the file does not have a
gamma value, you can pass one anyway if you wish. Note that file
gammas are inverted from screen gammas. See the discussions on
gamma in the PNG specification for more information. It is strongly
reccommended that viewers support gamma correction.
gamma in the PNG specification for more information.
if (info_ptr->valid & PNG_INFO_gAMA)
png_set_gamma(png_ptr, screen_gamma, info_ptr->gamma);
@ -397,7 +383,7 @@ times, or any of that other stuff necessary with png_read_rows().
where row_pointers is:
void *row_pointers[height];
png_bytep row_pointers[height];
You can point to void or char or whatever you use for pixels.
@ -412,7 +398,7 @@ row_pointers is the same as in the png_read_image() call.
If you are just calling one row at a time, you can do this for
row_pointers:
char *row_pointers = row;
png_bytep row_pointers = row;
png_read_rows(png_ptr, &row_pointers, NULL, 1);
@ -484,6 +470,133 @@ read or write. For a more compact example of reading a PNG image,
see the file example.c.
Reading PNG files progressively:
The progressive reader is slightly different then the non-progressive
reader. Instead of calling png_read_info(), png_read_rows(), and
png_read_end(), you make one call to png_process_data(), which calls
callbacks when it has the info, a row, or the end of the image. You
set up these callbacks with png_set_progressive_read_fn(). You don't
have to worry about the input/output functions of libpng, as you are
giving the library the data directly in png_process_data(). I will
assume that you have read the second on reading PNG files above,
so I will only highlight the differences (although I will show
all of the code).
png_structp png_ptr;
png_infop info_ptr;
int
initialize_png_reader()
{
png_ptr = malloc(sizeof (png_struct));
if (!png_ptr)
return -1;
info_ptr = malloc(sizeof (png_info));
if (!info_ptr)
{
free(png_ptr);
return -1;
}
if (setjmp(png_ptr->jmpbuf))
{
png_read_destroy(png_ptr, info_ptr, (png_info *)0);
/* free pointers before returning, if necessary */
free(png_ptr);
free(info_ptr);
return -1;
}
png_info_init(info_ptr);
png_read_init(png_ptr);
/* this one's new. You will need to provide all three
function callbacks, even if you aren't using them all.
You can put a void pointer in place of the NULL, and
retrieve the pointer from inside the callbacks using
the function png_get_progressive_ptr(png_ptr); */
png_set_progressive_read_fn(png_ptr, NULL,
info_callback, row_callback, end_callback);
return 0;
}
int
process_data(png_bytep buffer, png_uint_32 length)
{
if (setjmp(png_ptr->jmpbuf))
{
png_read_destroy(png_ptr, info_ptr, (png_info *)0);
free(png_ptr);
free(info_ptr);
return -1;
}
/* this one's new also. Simply give it a chunk of data
from the file stream (in order, of course). On Segmented
machines, don't give it any more then 64K. The library
seems to run fine with sizes of 4K, although you can give
it much less if necessary (I assume you can give it chunks
of 1 byte, but I haven't tried less then 256 bytes yet).
When this function returns, you may want to display any
rows that were generated in the row callback. */
png_process_data(png_ptr, info_ptr, buffer, length);
return 0;
}
info_callback(png_structp png_ptr, png_infop info)
{
do any setup here, including setting any of the transformations
mentioned in the Reading PNG files section. For now, you _must_
call either png_start_read_image() or png_read_update_info()
after all the transformations are set (even if you don't set
any). You may start getting rows before png_process_data()
returns, so this is your last chance to prepare for that.
}
row_callback(png_structp png_ptr, png_bytep new_row,
png_uint_32 row_num, int pass)
{
this function is called for every row in the image. If the
image is interlacing, and you turned on the interlace handler,
this function will be called for every row in every pass.
Some of these rows will not be changed from the previous pass.
When the row is not changed, the new_row variable will be NULL.
The rows and passes are called in order, so you don't really
need the row_num and pass, but I'm supplying them because it
may make your life easier.
For the non-NULL rows of interlaced images, you must call
png_progressive_combine_row() passing in the row and the
old row. You can call this function for NULL rows (it will
just return) and for non-interlaced images (it just does the
memcpy for you) if it will make the code easier. Thus, you
can just do this for all cases:
png_progressive_combine_row(png_ptr, old_row, new_row);
where old_row is what was displayed for previous rows. Note
that the first pass (pass == 0 really) will completely cover
the old row, so the rows do not have to be initialized. After
the first pass (and only for interlaced images), you will have
to pass the current row, and the function will combine the
old row and the new row.
}
end_callback(png_structp png_ptr, png_infop info)
{
this function is called when the whole image has been read,
including any chunks after the image (up to and including
the IEND). You will usually have the same info chunk as you
had in the header, although some data may have been added
to the comments and time fields.
Most people won't do much here, perhaps setting a flag that
marks the image as finished.
}
Writing PNG files:
Much of this is very similar to reading. However, everything of
@ -495,10 +608,10 @@ and initialize png_struct and png_info. As these are both large, you
may not want to store these on the stack, unless you have stack space
to spare.
png_struct *png_ptr = malloc(sizeof (png_struct));
png_structp png_ptr = malloc(sizeof (png_struct));
if (!png_ptr)
return;
png_info *info_ptr = malloc(sizeof (png_info));
png_infop info_ptr = malloc(sizeof (png_info));
if (!info_ptr)
{
free(png_ptr);
@ -524,11 +637,9 @@ setjmp and pass the jmpbuf field of your png_struct. If you
write the file from different routines, you will need to update
the jmpbuf field every time you enter a new routine that will
call a png_ function. See your documentation of setjmp/longjmp
for your compiler for more information on setjmp/longjmp. If you
don't want to use stderr for error output, or you want to use a
method other than setjmp()/longjmp() to handle errors, see the
Customizing Libpng section below for more information on libpng
error handling.
for your compiler for more information on setjmp/longjmp. See
the discussion on png error handling in the Customizing Libpng
section below for more information on the png error handling.
if (setjmp(png_ptr->jmpbuf))
{
@ -555,7 +666,7 @@ Now you need to set up the input code. The default for libpng is
to use the C function fwrite(). If you use this, you will need to
pass a valid FILE * in the function png_init_io(). Be sure that
the file is opened in binary mode. If you wish to handle writing
data in another way, see the discussion on PNG I/O handling in the
data in another way, see the discussion on png i/o handling in the
Customizing Libpng section below.
png_init_io(png_ptr, fp);
@ -563,7 +674,7 @@ Customizing Libpng section below.
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
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
@ -571,36 +682,14 @@ 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_filtering(png_ptr, 1);
/* compression level (0 - none, 6 - default, 9 - maximum) */
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);
It is possible to have libpng flush any pending output, either manually,
or automatically after a certain number of lines have been written. To
flush the output stream a single time call:
png_write_flush(png_ptr);
and to have libpng flush the output stream after a certain number of
scanlines have been written, call:
png_set_flush(png_ptr, nrows);
Note that the distance between rows is from the last time png_write_flush
was called, or the first row of the image if it has never been called.
So if you write 50 lines, and then png_set_flush 25, it will flush the
output on the next scanline, and on line 75, unless png_write_flush is
called earlier. If nrows is too small (less than about 10 lines) the
image compression may decrease dramatically (although this may be
acceptable for real-time applications). Infrequent flushing will only
degrade the compression performance by a few percent over images that
do not use flushing.
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 are allowed to write after the image is the text chunks and the
@ -623,7 +712,7 @@ parts of the png_info are:
appropriate PNG_INFO_<chunk name> define.
palette and num_palette - the palette for the file
gamma - the gamma the file is written at
sig_bit - the number of significant bits for red, green, blue, grey, alpha
sig_bit and sig_bit_number - the number of significant bits
trans, trans_values, and number_trans - transparency info
hist - histogram of palette
text and num_text - text comments in the file.
@ -656,20 +745,13 @@ you can leave off the text string on non-compressed pairs.
Compressed pairs must have a text string, as only the text string
is compressed anyway, so the compression would be meaningless.
PNG supports MODIFICATION time via the png_time structure. Two
PNG supports modification time via the png_time structure. Two
conversion routines are proved, png_convert_from_time_t() for
time_t and png_convert_from_struct_tm() for struct tm. The
time_t routine uses gmtime(). You don't have to use either of
these, but if you wish to fill in the png_time structure directly,
you should provide the time in universal time (GMT) if possible
instead of your local time. Note that the year number is the full
year number (ie 1995 rather than 95).
Since the CREATION time of an image is somewhat ambiguous, it is not
sensible to store an exact time like the tIME chunk above (ie when was
a scanned photo of neanderthal art created?). However, a text chunk
with a "Created" keyword can hold this information, in a form which is
useful (ie "Painted circa 40000 BC, photographed 1971, scanned 1996").
instead of your local time.
You are now ready to write all the file information up to the actual
image data. You do this with a call to png_write_info().
@ -760,7 +842,7 @@ times, or any of that other stuff necessary with png_write_rows().
where row_pointers is:
void *row_pointers[height];
png_bytef *row_pointers[height];
You can point to void or char or whatever you use for pixels.
@ -775,7 +857,7 @@ row_pointers is the same as in the png_write_image() call.
If you are just calling one row at a time, you can do this for
row_pointers:
char *row_pointers = row;
png_bytep row_pointers = row;
png_write_rows(png_ptr, &row_pointers, 1);
@ -831,43 +913,41 @@ standard things like memory allocation, input/output, and error handling.
The second deals with more complicated things like adding new chunks,
adding new transformations, and generally changing how libpng works.
All of the memory allocation in libpng is done in pngmem.c. Memory
allocation is done through the functions png_large_malloc(), png_malloc(),
png_realloc(), png_large_free(), and png_free(). These currently just
call the standard C functions. The large functions must handle at least
64K, but they don't have to handle more then that. If your pointers can't
access more then 64K at a time, you will want to set MAXSEG_64K in zlib.h.
All of the memory allocation, input/output, and error handling in libpng
goes through callbacks which are user setable. The default routines
are in pngerror.c, pngmem.c, and pngio.c. To change these functions,
call the approprate fn function.
Since it is unlikely that the method of handling memory allocation on a
platform will change between applications, these functions must be modified
or replaced to change their behaviour. If you only need to add new tests or
flags to have the compiler choose the correct function calls, please forward
these changes to the libpng author, so they can be added into the library
for the benefit of others.
Memory allocation is done through the functions png_large_malloc(),
png_malloc(), png_realloc(), png_large_free(), and png_free().
These currently just call the standard C functions. The large
functions must handle exactly 64K, but they don't have to handle
more then that. If your pointers can't access more then 64K at a
time, you will want to set MAXSEG_64K in zlib.h.
All of the input/output, and error handling in libpng go through the
routines in pngio.c by default. The file has plenty of comments describing
each function and how it expects to work. It is possible to supply different
I/O and error handling methods at run time with the png_set_msg_fn(),
png_set_read_fn(), and png_set_write_fn() calls.
Input/Output in libpng is done throught png_read() and png_write(), which
currently just call fread() and fwrite(). The FILE * is stored in
png_struct, and is initialized via png_init_io(). If you wish to change
this, the library supplies callbacks that you can set through the
function png_set_read_fn() and png_set_write_fn(). These functions
also provide a void pointer that can be retrieved via the function
png_get_io_ptr(). For example:
Input/Output in libpng is done throught png_read_data() and png_write_data(),
which currently just call fread() and fwrite(). The error and warning
functions png_error() and png_warning() use stderr to output any messages,
and png_error() uses longjmp to return from an error. These default
functions are set by via png_init_io().
png_set_read_fn(png_structp png_ptr, voidp io_ptr,
png_rw_ptr read_data_fn)
If you wish to change some or all of these functions, it is possible to
do so at runtime, and without modifying the libpng library code. The
application must supply replacement functions which have the same arguments
and are functionally equivalent to the default functions. If you are
replacing both the I/O and message functions, the call to png_init_io()
is not needed.
png_set_write_fn(png_structp png_ptr, voidp io_ptr,
png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn);
Error handling in libpng is done through png_error() and png_warning() by
default. Errors handled through png_error() are fatal, meaning that
png_error() should never return to it's caller. Currently, this is handled
via setjmp() and longjmp(), but you could change this to do things like
voidp io_ptr = png_get_io_ptr(png_ptr);
Note that you can pass NULL for the flush function if you are not doing
flushing.
Error handling in libpng is done through png_error() and png_warning().
Errors handled through png_error() are fatal, meaning that png_error()
should never return to it's caller. Currently, this is handled via
setjmp() and longjmp(), but you could change this to do things like
exit() if you should wish. Similarly, both png_error() and png_warning()
print a message on stderr, but that can also be changed. The motivation
behind using setjmp() and longjmp() is the C++ throw and catch exception
@ -876,72 +956,14 @@ is no need to check every return code of every function call. However,
there are some uncertainties about the status of local variables after
a longjmp, so the user may want to be careful about doing anything after
setjmp returns non zero besides returning itself. Consult your compiler
documentation for more details.
documentation for more details. If you wish to change this behavior,
you will need to set up your own message callbacks. You do this like
the io callbacks above.
The replacement message functions should have parameters as follows:
png_set_message_fn(png_structp png_ptr, png_voidp msg_ptr,
png_msg_ptr error_fn, png_msg_ptr warning_fn);
void user_error_fn(png_struct png_ptr, char *error_msg);
void user_warning_fn(png_struct png_ptr, char *warning_msg);
These functions can be attached to a PNG stream with a call
png_set_msg_fn(png_ptr, msg_ptr, user_error_fn, user_warning_fn);
If NULL is supplied for user_error_fn, then the error function will not
print any error messages, and will return via longjmp(png_ptr->jmpbuf,1) to
the last location setjmp(png_ptr->jmpbuf) was previously called. If NULL is
supplied for user_warning_fn then no warning messages will be printed.
In order to make it possible to have multiple PNG files open at the same
time, the replacement message functions should not modify any global
variables. In order to have any message information available to the
libpng streams, there is a pointer available to for a user variable or
structure. If more than one variable or structure of needs to be kept
with each stream, then you must create a structure which holds all the
relevant data. The pointer to this data is set in the initial png_set_msg_fn
call, and can be accessed with:
msg_ptr = (user_msg_type *)png_get_msg_ptr(png_ptr);
The replacement I/O functions should have prototypes as follows:
void user_read_data(png_struct *png_ptr,png_bytef *data,png_uint_32 length);
void user_write_data(png_struct *png_ptr,png_bytef *data,png_uint_32 length);
where the routine will read or write "length" bytes into or out of "data".
If the routines are unable to read or write the correct number of bytes, they
should call (*(png_ptr->error_fn))(png_ptr, "Error message"); to abort.
void user_output_flush(png_struct *png_ptr);
will flush any data from the buffer used by the output device. Note that
the flush function is purely to output any data being stored by the write
function, and has no control over any data buffered inside the compressor.
These functions can be attached to a PNG stream by calling one of
png_set_read_fn(png_ptr, io_ptr, user_read_data);
png_set_write_fn(png_ptr, io_ptr, user_write_data, user_output_flush);
You should only call one of these two functions for a single PNG stream.
It is a fatal error to read from a write stream, and vice-versa. If the
output method you are using does not buffer any data, or you have chosen
not to compile libpng with PNG_WRITE_FLUSH_SUPPORTED, NULL may be supplied
instead of a function name for user_output_flush, and an empty function will
be used. Note that even if the output method being used does not buffer
output, during compression data is buffered by the compressor. If an
application wants to guarantee that all pending output data has been written,
it should call png_write_flush, which will flush the compression buffers,
and in turn call the user_output_flush function.
As with the message functions, the replacement I/O functions should not
modify any global variables. Therse is a separate pointer available to for
an I/O variable or structure. If more than one variable or structure of
needs to be kept with each stream, then you must create a structure which
holds all the relevant data. The pointer to this data is set in the initial
set_xxx_fn call, and can be accessed with:
io_ptr = (user_io_type *)png_get_io_ptr(png_ptr);
png_voidp msg_ptr = png_get_msg_ptr(png_ptr);
If you need to read or write custom chunks, you will need to get deeper
into the libpng code. First, read the PNG specification, and have
@ -950,9 +972,7 @@ attention to the sections that describe chunk names, and look
at how other chunks were designed, so you can do things similar.
Second, check out the sections of libpng that read and write chunks.
Try to find a chunk that is similar to yours, and copy off of it.
More details can be found in the comments inside the code. If you are
truly ambitious, you can modify the libpng code to handle unknown chunks
in a general way and send the code to the libpng author.
More details can be found in the comments inside the code.
If you wish to write your own transformation for the data, look
through the part of the code that does the transformations, and check
@ -963,21 +983,32 @@ itself.
Configuring for 16 bit platforms:
You will probably need to change the png_large_malloc() and
png_large_free() routines in pngmem.c, as these are required
You will may need to change the png_large_malloc() and
png_large_free() routines in pngmem.c, as these are requred
to allocate 64K. Also, you will want to look into zconf.h to tell
zlib (and thus libpng) that it cannot allocate more then 64K at a
time. Even if you can, the memory won't be accessable. So limit zlib
and libpng to 64K by defining MAXSEG_64K.
Configuring for Medium Model:
Libpng's support for medium model has been tested on most of the popular
complers. Make sure MAXSEG_64K get's defined, USE_FAR_KEYWORD get's
defined, and FAR get's defined to far in pngconf.h, and you should be
all set. Everything in the library (except for zlib's structure) is
expecting far data. You must use the typedefs with the p or pp on
the end for pointers (or at least look at them and be careful). Make
note that the row's of data are defined as png_bytepp which is a
unsigned char far * far *
Configuring for gui/windowing platforms:
You will need to supply new message display functions for png_error() and
png_warning() (through png_set_message_fn() to display a message in a window
instead of fprinting it to stderr. You may want to write a single function
to do this and call it something like png_message() (although the error
function should still call longjmp or otherwise handle the error without
returning).
You will need to change the error message display in png_error() and
png_warning() to display a message instead of fprinting it to stderr.
You may want to write a single function to do this and call it something
like png_message(). On some compliers, you may have to change the
memory allocators (png_malloc, etc.).
Configuring for compiler xxx:
@ -989,13 +1020,15 @@ files in libpng proper only include png.h.
Removing unwanted object code:
There are a bunch of #define's in pngconf.h that control what parts of
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
never going to use an ability, you can change the #define to #undef and
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.
both reading and writing, and always need to be included. The
progressive reader is in pngpread.c

190
lpfaq.txt
View File

@ -1,190 +0,0 @@
libpng FAQ - August 20, 1995
Maintainer:
Guy Eric Schalnat: schalnat@group42.com CompuServe: 75501,1625
Contents:
1) General Questions
1.1) How official is this FAQ?
1.2) How often is this FAQ posted?
1.3) Where can I get this FAQ, libpng, zlib, the PNG
specification, test images, etc.?
1.4) How ready is libpng?
1.5) How portable is libpng?
1.6) When will libpng be out of Beta?
1.7) What remains to be done in libpng for the 1.0 release?
1.8) Can I help?
1.9) Why don't you answer your mail?
2) Libpng questions
2.1) Does the order of functions calls matter?
2.2) When I try to read/write a png image, it doesn't work.
2.3) Do I have to start with example.c?
2.4) What things should I be careful of?
2.5) Why doesn't example.c compile?
3) Critical Patches
No known bugs (for now :-).
4) Non-critical patches
No known bugs (for now :-).
Questions:
1) General Questions
1.1) How official is this FAQ?
As it was written by the author of libpng (that's me :), it's
about offical as one can get. However, it is not ready for
prime time yet, as libpng is still in beta, and thus its
users are of the sort that are willing to deal with beta
software. Thus, I assume all of you reading this have a
basic familiarity with PNG, libpng, and C programming. I'll
write a basic section for libpng later, as well as some quick
stuff on PNG itself (but this will not be the PNG FAQ. I just
don't have that kind of time).
1.2) How often is this FAQ posted?
As often as events warrant. I doubt it'll get stale, and as
it is not (and may never be) actually posted to a newsgroup,
I feel no need to make monthy postings.
1.3) Where can I get this FAQ, libpng, zlib, the PNG
specification, test images, etc.?
Everything should be at ftp://ftp.uu.net/graphics/png and
mirror sites. On CompuServe, it should be at GO GRAPHSUPPORT
in the Png Development library (lib 20). Failing that, try
my ftp site at ftp://ftp.group42.com/pub/png or web site at
http://www.group42.com/ If you have trouble getting to these,
the numerical address is 204.94.158.25
1.4) How ready is libpng?
In its current incarnation (0.8), it still may have a few bugs.
I think I got all of the bugs this time, but one never knows.
Also, the dithering currently in libpng is horrid, so that
needs work. Finally, I have yet to implement medium model
support.
1.5) How portable is libpng?
As portable as I can make it. It needs int's of at least
16 bits, and longs of at least 32 bits. It has not been
tried for char's larger then 8 bits. It should support
any reasonable K&R C compiler, as well as any ANSI C
compiler. The most you should need to do is change the
includes in pngconf.h. So far, I know of no compiler in use
that libpng will not compile on.
1.6) When will libpng be out of Beta?
That depends on my workload here. I'm writing libpng for
free, which generates tons of good will, but doesn't help
put food on the table, so there are times I just can't do
any real work on it. There is still some work to be done
(see question 1.7), so don't expect the official version
before September (and that may be pushing it). I'll try
to get the next (last?) beta version out my early
September. Be warned, I always seem to take twice as
long as I think I will.
1.7) What remains to be done in libpng for the 1.0 release?
Add Tim Wegner's medium memory model support. (Thanks, Tim).
Improve the dithering.
Rewrite libpng.txt, and comment the code better.
Test with a final zlib.
1.8) Can I help?
Sweet words. The most helpful thing you can do for the
1.0 release is help testing on your compiler. After this
release, though, there is a large list of things that ought
to be done to make libpng be more full featured. We'll
talk about this later, as I don't want to add tons of new
code until after 1.0 gets out the door. Please send me
any makefile changes and/or other changes needed to support
your compiler (with a #ifdef for the code changes).
If any of you are good at technical writing, take a look at
libpng.txt and correct it (or rewrite it) as necessary. I
am not a writer, I'm a programmer. It shows.
1.9) Why don't you answer your mail?
I've been busy. I'm sorry about that, and I've got to get
into the habit of at least replying that I got the message.
Also, some of you have sent me problems that I haven't gotten
back to you yet. If it is still a problem, you may want to
give me a short message and remind me that I need to look into
it. Libpng is being tested by more people than I dared hope
(which is a good thing), and I was unprepared to deal with so
many problems so soon.
2) Libpng questions
2.1) Does the order of functions calls matter?
In general, yes. If you stick with the order I used in libpng.txt
and example.c, you should be safe. Be warned, however, that I
messed up the order of png_set_interlace_handling(). It needs
to be called *before* png_start_read_image(), not after. Oops.
The exceptions to this rule are all the png_set ... calls.
They can be done in any order, but they all have to be done
in the area indicated by libpng.txt/example.c.
2.2) When I try to read/write a png image, it doesn't work.
Does zlib's test program work (example.c)? Does libpng's test
program work (testpng.c)? Have you installed the patches at
the end of this FAQ? After all that, if the problem continues,
e-mail me, and we'll try to fix it. If you don't have much
programming experience, be patient about the fix. Code
fragments help, as do *small* images (uuencoded please). If
I don't get back to you right away, give me some time. Thanks.
2.3) Do I have to start with example.c?
No, but most people have had much better luck doing that. Seems
I didn't explain things well in libpng.txt, so things are not
intuitive to people (which could be an api design problem also).
Sometime in the future, we'll revisit the api design, and try
to make it easier to use. I'll rewrite libpng.txt before the
1.0 release.
2.4) What things should I be careful of?
The main gotcha is calling png_read_init() before png_info_init().
Also, always make sure you have a correct setjmp buffer. That's
all I can think of for now.
2.5) Why doesn't example.c compile?
I wrote example.c as a staring point for using libpng. It doesn't
compile because I don't know how you want to do things like allocating
memory to hold the image, so I left that code out. If you go in and
finish it up, it should work fine. The file pngtest.c gives a
very simple example of reading and writing png files.
3) Critical Patches
No known bugs (for now :-).
4) Non-critical patches
No known bugs (for now :-).
That's it so far as I know. If I missed something, yell.
-Guy

15
makefile
View File

@ -2,26 +2,25 @@
# Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
# For conditions of distribution and use, see copyright notice in png.h
CC=gcc
CFLAGS=-I../zlib -O2 -Wall -ansi -pedantic
CC=cc
CFLAGS=-I../zlib -O
LDFLAGS=-L. -L../zlib/ -lpng -lz -lm
RANLIB=ranlib
#RANLIB=echo
#RANLIB=ranlib
RANLIB=echo
# where make install puts libpng.a and png.h
prefix=/home/munet-d2/sun/local
prefix=/usr/local
OBJS = png.o pngrcb.o pngrutil.o pngtrans.o pngwutil.o \
pngread.o pngio.o pngwrite.o pngrtran.o pngwtran.o \
pngmem.o
pngmem.o pngerror.o pngpread.o
all: libpng.a pngtest
libpng.a: $(OBJS)
ar rc $@ $(OBJS)
$(RANLIB) $@
rcp libpng.a vlsi:bin/lib/libpng.a
pngtest: pngtest.o libpng.a
$(CC) -o pngtest $(CCFLAGS) pngtest.o $(LDFLAGS)
@ -45,6 +44,7 @@ clean:
# DO NOT DELETE THIS LINE -- make depend depends on it.
png.o: png.h pngconf.h
pngerror.o: png.h pngconf.h
pngio.o: png.h pngconf.h
pngmem.o: png.h pngconf.h
pngrcb.o: png.h pngconf.h
@ -56,3 +56,4 @@ pngtrans.o: png.h pngconf.h
pngwrite.o: png.h pngconf.h
pngwtran.o: png.h pngconf.h
pngwutil.o: png.h pngconf.h
pngpread.o: png.h pngconf.h

78
png.c
View File

@ -1,10 +1,10 @@
/* png.c - location for general purpose png functions
libpng 1.0 beta 2 - version 0.81
libpng 1.0 beta 2 - version 0.85
For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
August 24, 1995
December 19, 1995
*/
#define PNG_INTERNAL
@ -13,115 +13,119 @@
/* version information for c files. This better match the version
string defined in png.h */
char png_libpng_ver[] = "0.81";
char FARDATA png_libpng_ver[] = "0.85";
/* 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 FARDATA png_sig[8] = {137, 80, 78, 71, 13, 10, 26, 10};
/* constant strings for known chunk types. If you need to add a chunk,
add a string holding the name here. If you want to make the code
portable to EBCDIC machines, use ASCII numbers, not characters. */
png_byte png_IHDR[4] = { 73, 72, 68, 82};
png_byte png_IDAT[4] = { 73, 68, 65, 84};
png_byte png_IEND[4] = { 73, 69, 78, 68};
png_byte png_PLTE[4] = { 80, 76, 84, 69};
png_byte FARDATA png_IHDR[4] = { 73, 72, 68, 82};
png_byte FARDATA png_IDAT[4] = { 73, 68, 65, 84};
png_byte FARDATA png_IEND[4] = { 73, 69, 78, 68};
png_byte FARDATA 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 FARDATA 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 FARDATA 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 FARDATA 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 FARDATA 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 FARDATA 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 FARDATA 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 FARDATA 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 FARDATA 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 FARDATA 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 FARDATA 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 FARDATA png_tIME[4] = {116, 73, 77, 69};
#endif
/* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
/* start of interlace block */
int png_pass_start[] = {0, 4, 0, 2, 0, 1, 0};
int FARDATA png_pass_start[] = {0, 4, 0, 2, 0, 1, 0};
/* offset to next interlace block */
int png_pass_inc[] = {8, 8, 4, 4, 2, 2, 1};
int FARDATA png_pass_inc[] = {8, 8, 4, 4, 2, 2, 1};
/* start of interlace block in the y direction */
int png_pass_ystart[] = {0, 0, 4, 0, 2, 0, 1};
int FARDATA png_pass_ystart[] = {0, 0, 4, 0, 2, 0, 1};
/* offset to next interlace block in the y direction */
int png_pass_yinc[] = {8, 8, 8, 4, 4, 2, 2};
int FARDATA png_pass_yinc[] = {8, 8, 8, 4, 4, 2, 2};
/* width of interlace block */
/* this is not currently used - if you need it, uncomment it here and
in png.h
int png_pass_width[] = {8, 4, 4, 2, 2, 1, 1};
int FARDATA png_pass_width[] = {8, 4, 4, 2, 2, 1, 1};
*/
/* height of interlace block */
/* this is not currently used - if you need it, uncomment it here and
in png.h
int png_pass_height[] = {8, 8, 4, 4, 4, 2, 2, 1};
int FARDATA png_pass_height[] = {8, 8, 4, 4, 2, 2, 1};
*/
/* mask to determine which pixels are valid in a pass */
int png_pass_mask[] = {0x80, 0x08, 0x88, 0x22, 0xaa, 0x55, 0xff};
int FARDATA png_pass_mask[] = {0x80, 0x08, 0x88, 0x22, 0xaa, 0x55, 0xff};
/* mask to determine which pixels to overwrite while displaying */
int png_pass_dsp_mask[] = {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, 0xff};
int FARDATA png_pass_dsp_mask[] = {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, 0xff};
int
png_check_sig(png_byte *sig, int num)
png_check_sig(png_bytep sig, int num)
{
if (num > 8)
num = 8;
if (num < 1)
return 0;
return (!memcmp(sig, png_sig, num));
return (!png_memcmp(sig, png_sig, num));
}
/* Function to allocate memory for zlib. */
voidpf
png_zalloc(voidpf png_ptr, uInt items, uInt size)
{
return ((voidpf)png_large_malloc((png_struct FAR *)png_ptr,
voidp * ptr;
ptr = ((voidp)png_large_malloc((png_structp)png_ptr,
(png_uint_32)items * (png_uint_32)size));
png_memset(ptr, 0, (png_uint_32)items * (png_uint_32)size);
return (voidpf)(ptr);
}
/* function to free memory for zlib */
void
png_zfree(voidpf png_ptr, voidpf ptr)
{
png_large_free((png_struct FAR *)png_ptr, (voidpf)ptr);
png_large_free((png_structp)png_ptr, (voidp)ptr);
}
/* reset the crc variable to 32 bits of 1's. Care must be taken
in case crc is > 32 bits to leave the top bits 0 */
void
png_reset_crc(png_struct *png_ptr)
png_reset_crc(png_structp png_ptr)
{
/* set crc to all 1's */
png_ptr->crc = 0xffffffffL;
@ -161,10 +165,10 @@ make_crc_table(void)
initialized to all 1's, and the transmitted value is the 1's complement
of the final running crc. */
static png_uint_32
update_crc(png_uint_32 crc, png_bytef *buf, png_uint_32 len)
update_crc(png_uint_32 crc, png_bytep buf, png_uint_32 len)
{
png_uint_32 c;
png_bytef *p;
png_bytep p;
png_uint_32 n;
c = crc;
@ -189,15 +193,15 @@ update_crc(png_uint_32 crc, png_bytef *buf, png_uint_32 len)
would need to use huge pointers to access all that data. If you
need this, put huge here and above. */
void
png_calculate_crc(png_struct *png_ptr, png_bytef *ptr,
png_calculate_crc(png_structp png_ptr, png_bytep ptr,
png_uint_32 length)
{
png_ptr->crc = update_crc(png_ptr->crc, ptr, length);
}
void
png_info_init(png_info *info)
png_info_init(png_infop info)
{
/* set everything to 0 */
memset(info, 0, sizeof (png_info));
png_memset(info, 0, sizeof (png_info));
}

718
png.h
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File diff suppressed because it is too large Load Diff

16
pngchang.txt
View File

@ -56,15 +56,11 @@ version 0.8
enabled png_set_shift to work with paletted images on read
added png_read_update_info() - updates info structure with transformations
version 0.81
added support for medium memory model
version 0.82
added ability to flush output stream automatically or manually
added ability to change I/O and error functions dynamically
moved pngerror.c into pngio.c to make all the default functions static
when freeing memory in png_read_destroy don't free memory we didn't allocate
added warnings when reading blocks of incorrect length
limit tEXt and zTXt keywords to 80 chars
incorporated Tim Wegner's medium model code (thanks, Tim)
version 0.85
added more medium model code (almost everythings a far)
added i/o, error, and memory callback functions
fixed some bugs (16 bit, 4 bit interlaced, etc.)
added first run progressive reader (barely tested)

118
pngconf.h
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@ -1,10 +1,10 @@
/* pngconf.c - machine configurable file for libpng
libpng 1.0 beta 2 - version 0.81
libpng 1.0 beta 2 - version 0.85
For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
August 24, 1995
December 19, 1995
*/
/* Any machine specific code is near the front of this file, so if you
@ -27,7 +27,7 @@
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 32768
#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
@ -48,6 +48,14 @@
#define PNG_MAX_ALLOC_64K
#endif
/* this protects us against compilers which run on a windowing system
and thus don't have or would rather us not use the stdio types:
stdin, stdout, and stderr. The only one currently used is stderr
in png_error() and png_warning(). #defining PNG_NO_STDIO will
prevent these from being compiled and used. */
/* #define PNG_NO_STDIO */
/* 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
@ -60,7 +68,7 @@
#else
#ifdef _NO_PROTO
#define PNGARG(arglist)
#define PNGARG(arglist) ()
#else
#define PNGARG(arglist) arglist
#endif /* _NO_PROTO */
@ -129,6 +137,19 @@
#endif /* PNG_INTERNAL */
/* the following uses const char * instead of char * for error
and warning message functions, so some compilers won't complain.
If you want to use const, define PNG_USE_CONST here. It is not
normally defined to make configuration easier, as it is not a
critical part of the code.
*/
#ifdef PNG_USE_CONST
# define PNG_CONST const
#else
# define PNG_CONST
#endif
/* 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
@ -144,7 +165,7 @@
*/
/* Any transformations you will not be using can be undef'ed here */
#define PNG_PROGRESSIVE_READ_SUPPORTED
#define PNG_READ_INTERLACING_SUPPORTED
#define PNG_READ_EXPAND_SUPPORTED
#define PNG_READ_SHIFT_SUPPORTED
@ -223,16 +244,96 @@ typedef size_t png_size_t;
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
/* SJT: Separate compiler dependencies */
/* SJT: problem here is that zlib.h always defines FAR */
#ifdef __BORLANDC__
#if defined(__LARGE__) || defined(__HUGE__) || defined(__COMPACT__)
#define LDATA 1
#else
#define LDATA 0
#endif
#if !defined(__WIN32__) && !defined(__FLAT__)
#define PNG_MAX_MALLOC_64K
#if (LDATA != 1)
#ifndef FAR
#define FAR __far
#endif
#define USE_FAR_KEYWORD
#endif /* LDATA != 1 */
/* SJT: Possibly useful for moving data out of default segment.
Uncomment it if you want. Could also define FARDATA as const
if your compiler supports it.
# define FARDATA FAR
*/
#endif /* __WIN32__, __FLAT__ */
#endif /* __BORLANDC__ */
/* SJT: Suggest testing for specific compiler first before
testing for FAR. The Watcom compiler defines both __MEDIUM__
and M_I86MM, making reliance oncertain keywords suspect
*/
/* MSC Medium model */
#if defined(FAR)
# if defined(M_I86MM)
# define USE_FAR_KEYWORD
# define FARDATA FAR /* SJT: added */
# endif
#endif
/* SJT: default case */
#ifndef FAR
# define FAR
#endif
/* SJT: At this point FAR is always defined */
/* not used anymore, but kept for compatability */
typedef unsigned char FAR png_bytef;
/* SJT: */
#ifndef FARDATA
#define FARDATA
#endif
/* End medium model changes to be in zconf.h */
/* SJT: More typedefs */
typedef void FAR * png_voidp;
/* SJT: Add typedefs for pointers */
typedef png_byte FAR * png_bytep;
typedef png_uint_32 FAR * png_uint_32p;
typedef png_int_32 FAR * png_int_32p;
typedef png_uint_16 FAR * png_uint_16p;
typedef png_int_16 FAR * png_int_16p;
typedef PNG_CONST char FAR * png_const_charp;
typedef char FAR * png_charp;
/* SJT: Pointers to pointers; i.e. arrays */
typedef png_byte FAR * FAR * png_bytepp;
typedef png_uint_32 FAR * FAR * png_uint_32pp;
typedef png_int_32 FAR * FAR * png_int_32pp;
typedef png_uint_16 FAR * FAR * png_uint_16pp;
typedef png_int_16 FAR * FAR * png_int_16pp;
typedef PNG_CONST char FAR * FAR * png_const_charpp;
typedef char FAR * FAR * png_charpp;
/* SJT: libpng typedefs for types in zlib. If Zlib changes
or another compression library is used, then change these.
Eliminates need to change all the source files.
*/
typedef charf * png_zcharp;
typedef charf * FAR * png_zcharpp;
typedef z_stream * png_zstreamp; /* zlib won't accept far z_stream */
/* 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 */
@ -240,6 +341,7 @@ typedef unsigned char FAR png_bytef;
# define png_strcat _fstrcat
# define png_strlen _fstrlen
# define png_strcmp _fstrcmp
# define png_memcmp _fmemcmp /* SJT: added */
# define png_memcpy _fmemcpy
# define png_memset _fmemset
#else /* use the usual functions */
@ -247,11 +349,11 @@ typedef unsigned char FAR png_bytef;
# define png_strcat strcat
# define png_strlen strlen
# define png_strcmp strcmp
# define png_memcmp memcmp /* SJT: added */
# define png_memcpy memcpy
# define png_memset memset
#endif
/* End of memory model independent support */
#endif /* PNGCONF_H */

99
pngerror.c Normal file
View File

@ -0,0 +1,99 @@
/* pngerror.c - stub functions for i/o and memory allocation
libpng 1.0 beta 2 - version 0.85
For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
December 19, 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_structp png_ptr, png_const_charp message)
{
if (png_ptr->error_fn)
(*(png_ptr->error_fn))(png_ptr, message);
/* if the following returns or doesn't exist, use the default function,
which will not return */
png_default_error(png_ptr, message);
}
void
png_warning(png_structp png_ptr, png_const_charp message)
{
if (png_ptr->warning_fn)
(*(png_ptr->warning_fn))(png_ptr, message);
else
png_default_warning(png_ptr, message);
}
void
png_default_error(png_structp png_ptr, png_const_charp message)
{
#ifndef PNG_NO_STDIO
fprintf(stderr, "libpng error: %s\n", message);
#endif
#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_default_warning(png_structp png_ptr, png_const_charp message)
{
if (!png_ptr)
return;
#ifndef PNG_NO_STDIO
fprintf(stderr, "libpng warning: %s\n", message);
#endif
}
/* This function is called when the application wants to use another
method of handling errors and warnings. Note that the error function must
NOT return to the calling routine or serious problems will occur. The
error return method used in the default routine calls
longjmp(png_ptr->jmpbuf, 1) */
void
png_set_message_fn(png_structp png_ptr, png_voidp msg_ptr, png_msg_ptr error_fn,
png_msg_ptr warning_fn)
{
png_ptr->msg_ptr = msg_ptr;
png_ptr->error_fn = error_fn;
png_ptr->warning_fn = warning_fn;
}
/* This function returns a pointer to the msg_ptr associated with the user
functions. The application should free any memory associated with this
pointer before png_write_destroy and png_read_destroy are called. */
png_voidp
png_get_msg_ptr(png_structp png_ptr)
{
return png_ptr->msg_ptr;
}

279
pngio.c
View File

@ -1,11 +1,10 @@
/* pngio.c - default functions for data I/O and error/warning messages
/* pngstub.c - stub functions for i/o and memory allocation
libpng 1.0 beta 3 - version 0.82
libpng 1.0 beta 2 - version 0.85
For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
Some portions Copyright (C) 1995 Andreas Dilger
Sept 24, 1995
December 19, 1995
This file provides a location for all input/output. Users which need
special handling are expected to write functions which have the same
@ -14,9 +13,9 @@
but rather write replacement functions and then change them at run
time with png_set_write_fn(...) or png_set_read_fn(...), etc */
#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 a good example of how to do it. Note that this routine
@ -24,16 +23,26 @@
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. */
void
png_write_data(png_structp png_ptr, png_bytep data, png_uint_32 length)
{
if (png_ptr->write_data_fn)
(*(png_ptr->write_data_fn))(png_ptr, data, length);
else
png_error(png_ptr, "Call to NULL write function");
}
#ifndef USE_FAR_KEYWORD
static void
png_write_data(png_struct *png_ptr, png_bytef *data, png_uint_32 length)
void
png_default_write_data(png_structp png_ptr, png_bytep data, png_uint_32 length)
{
png_uint_32 check;
check = fwrite(data, 1, (png_size_t)length, png_ptr->fp);
if (check != length)
{
(*(png_ptr->error_fn))(png_ptr, "Write error");
png_error(png_ptr, "Write Error");
}
}
#else
@ -50,8 +59,8 @@ png_write_data(png_struct *png_ptr, png_bytef *data, png_uint_32 length)
#include <dos.h>
#endif
static void
png_write_data(png_struct *png_ptr, png_bytef *data, png_uint_32 length)
void
png_default_write_data(png_structp png_ptr, png_bytep data, png_uint_32 length)
{
png_uint_32 check;
png_byte *n_data;
@ -64,7 +73,7 @@ png_write_data(png_struct *png_ptr, png_bytef *data, png_uint_32 length)
#else
/* this works in MSC also but with lost segment warning */
n_data = (png_byte *)data;
if((png_bytef *)n_data == data)
if ((png_bytep)n_data == data)
#endif
{
check = fwrite(n_data, 1, (png_size_t)length, png_ptr->fp);
@ -91,35 +100,56 @@ png_write_data(png_struct *png_ptr, png_bytef *data, png_uint_32 length)
}
if (check != length)
{
(*(png_ptr->error_fn))(png_ptr, "Write error");
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 a good example of how to do it. 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. */
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_structp png_ptr, png_bytep data, png_uint_32 length)
{
#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
if (png_ptr->read_mode == PNG_READ_PUSH_MODE)
{
png_push_fill_buffer(png_ptr, data, length);
}
else
#endif
{
if (png_ptr->read_data_fn)
(*(png_ptr->read_data_fn))(png_ptr, data, length);
else
png_error(png_ptr, "Call to NULL read function");
}
}
#ifndef USE_FAR_KEYWORD
static void
png_read_data(png_struct *png_ptr, png_bytef *data, png_uint_32 length)
void
png_default_read_data(png_structp png_ptr, png_bytep data, png_uint_32 length)
{
png_uint_32 check;
check = fread(data, 1, (size_t)length, png_ptr->fp);
if (check != length)
{
(*(png_ptr->error_fn))(png_ptr, "Read error");
png_error(png_ptr, "Read Error");
}
}
#else
static void
png_read_data(png_struct *png_ptr, png_bytef *data, png_uint_32 length)
void
png_default_read_data(png_structp png_ptr, png_bytep data, png_uint_32 length)
{
png_uint_32 check;
png_byte *n_data;
@ -132,7 +162,7 @@ png_read_data(png_struct *png_ptr, png_bytef *data, png_uint_32 length)
#else
/* this works in MSC also but with lost segment warning */
n_data = (png_byte *)data;
if((png_bytef *)n_data == data)
if ((PNG_BYTEP )n_data == data)
#endif
{
check = fread(n_data, 1, (size_t)length, png_ptr->fp);
@ -159,105 +189,30 @@ png_read_data(png_struct *png_ptr, png_bytef *data, png_uint_32 length)
}
if (check != length)
{
(*(png_ptr->error_fn))(png_ptr, "Read error");
png_error(png_ptr, "read Error");
}
}
#endif
/* This function does nothing, and is used for the write function on
a read, and vice-versa. It is an error if this function is
actually called. */
static void
png_empty_rw(png_struct *png_ptr, png_bytef *data, png_uint_32 length)
{
if (png_ptr->read_data_fn == png_empty_rw)
{
(*(png_ptr->error_fn))(png_ptr, "Invalid read on a write device");
}
else /* if (png_ptr->write_data_fn == png_empty_rw) */
{
(*(png_ptr->error_fn))(png_ptr, "Invalid write on a read device");
}
}
#if defined(PNG_WRITE_FLUSH_SUPPORTED)
/* This function does nothing, and is supplied for user I/O functions which
do not do any buffering. This function is set when NULL is supplied for
the flush function pointer. */
static void
png_empty_flush(png_struct *png_ptr)
void
png_flush(png_struct *png_ptr)
{
if (png_ptr->output_flush_fn)
(*(png_ptr->output_flush_fn))(png_ptr);
}
/* Write out any remaining output that is stored in the output buffers.
If you supply a new write routine, you will probably need to supply a
replacement for this routine as well. */
static void
png_output_flush(png_struct *png_ptr)
void
png_default_flush(png_struct *png_ptr)
{
if (png_ptr->fp)
fflush(png_ptr->fp);
}
#endif /* PNG_WRITE_FLUSH_SUPPORTED */
/* This function does nothing, and is called if the user supplies null
when setting the error function. */
static void
png_empty_error(png_structf *png_ptr, char *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 whenever there is an error. Replace with a
function you wish to handle the error. Note that this function
MUST NOT return, or the program will crash. To be consistent with
the examples for the library and this function, you could call
longjmp(pnt_ptr->jmpbuf) to return to the program at the location of
the last setjmp(png_ptr->jmpbuf) after an error. */
static void
png_error(png_structf *png_ptr, char *message)
{
fprintf(stderr, "libpng error: %s\n", message);
png_empty_error(png_ptr, message);
}
/* This function does nothing, and is called if the user supplies null
when setting the warning function. */
static void
png_empty_warning(png_struct *png_ptr, char *message)
{
}
/* 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. */
static void
png_warning(png_struct *png_ptr, char *message)
{
fprintf(stderr, "libpng warning: %s\n", message);
}
/* This function allows the application to supply new output functions for
libpng if standard C streams aren't being used. The new write function
should call (*(png_ptr->error_fn))("Error message") to exit and output
any fatal error messages if it cannot output the correct number of bytes.
libpng if standard C streams aren't being used.
This function takes as its arguments:
png_ptr - pointer to a png output data structure
io_ptr - pointer to user supplied structure containing info about
@ -277,38 +232,31 @@ png_warning(png_struct *png_ptr, char *message)
compile time, output_flush_fn will be ignored, although
it must be supplied for compatibility. */
void
png_set_write_fn(png_struct *png_ptr, void *io_ptr, png_rw_ptr write_data_fn,
png_set_write_fn(png_structp png_ptr, png_voidp io_ptr, png_rw_ptr write_data_fn,
png_flush_ptr output_flush_fn)
{
png_ptr->io_ptr = io_ptr;
if (write_data_fn == NULL)
{
(*(png_ptr->error_fn))(png_ptr, "NULL write function pointer given");
}
if (write_data_fn)
png_ptr->write_data_fn = write_data_fn;
else
png_ptr->write_data_fn = png_default_write_data;
#if defined(PNG_WRITE_FLUSH_SUPPORTED)
if (output_flush_fn == NULL)
{
png_ptr->output_flush_fn = png_empty_flush;
}
png_ptr->output_flush_fn = png_default_flush;
else
{
png_ptr->output_flush_fn = output_flush_fn;
}
#endif /* PNG_WRITE_FLUSH_SUPPORTED */
/* It is an error to write to a read device */
png_ptr->read_data_fn = png_empty_rw;
/* It is an error to read while writing a png file */
png_ptr->read_data_fn = NULL;
}
/* This function allows the application to supply a new input function
for libpng if standard C streams aren't being used. The new read function
should call (*(png_ptr->error_fn))("Error message") to exit and output
any fatal error messages if the desired number of bytes is not available.
for libpng if standard C streams aren't being used.
This function takes as its arguments:
png_ptr - pointer to a png input data structure
io_ptr - pointer to user supplied structure containing info about
@ -322,17 +270,16 @@ png_set_read_fn(png_struct *png_ptr, void *io_ptr, png_rw_ptr read_data_fn)
{
png_ptr->io_ptr = io_ptr;
if (read_data_fn == NULL)
{
(*(png_ptr->error_fn))(png_ptr, "NULL read function pointer given");
}
if (read_data_fn)
png_ptr->read_data_fn = read_data_fn;
else
png_ptr->read_data_fn = png_default_read_data;
/* It is an error to write to a read device */
png_ptr->write_data_fn = png_empty_rw;
png_ptr->write_data_fn = NULL;
#if defined(PNG_WRITE_FLUSH_SUPPORTED)
png_ptr->output_flush_fn = png_empty_flush;
png_ptr->output_flush_fn = NULL;
#endif /* PNG_WRITE_FLUSH_SUPPORTED */
}
@ -346,66 +293,18 @@ png_get_io_ptr(png_struct *png_ptr)
return png_ptr->io_ptr;
}
/* This function is called when the application wants to use another
method of handling errors and warnings. Note that the error function must
NOT return to the calling routine or serious problems will occur. The
error return method used in the default routine calls
longjmp(png_ptr->jmpbuf, 1), or exits if setjmp(png_ptr->jmpbuf) has never
been called. */
/* 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_set_msg_fn(png_struct *png_ptr, void *msg_ptr, png_msg_ptr error_fn,
png_msg_ptr warning_fn)
{
png_ptr->msg_ptr = msg_ptr;
if (error_fn == NULL)
{
png_ptr->error_fn = png_empty_error;
}
else
{
png_ptr->error_fn = error_fn;
}
if (warning_fn == NULL)
{
png_ptr->warning_fn = png_empty_warning;
}
else
{
png_ptr->warning_fn = warning_fn;
}
}
/* This function returns a pointer to the msg_ptr associated with the user
functions. The application should free any memory associated with this
pointer before png_write_destroy and png_read_destroy are called. */
void *
png_get_msg_ptr(png_struct *png_ptr)
{
return png_ptr->msg_ptr;
}
/* Initialize the default input/output functions for the png file.
If you change the read, write or message routines, can call
either png_set_read_fn(...), png_set_write_fn(...), etc. to change
individual functions after a call to png_init_io(...). You can also
call one of png_set_read_fn(...) or png_set_write_fn(...), AND
png_set_msg_fn(...) instead of png_init_io(...) if you aren't using
any of the default libpng functions. */
void
png_init_io(png_struct *png_ptr, FILE *fp)
png_init_io(png_structp png_ptr, FILE *fp)
{
png_ptr->fp = fp;
png_ptr->error_fn = png_error;
png_ptr->warning_fn = png_warning;
png_ptr->write_data_fn = png_write_data;
png_ptr->read_data_fn = png_read_data;
#if defined(PNG_WRITE_FLUSH_SUPPORTED)
png_ptr->output_flush_fn = png_output_flush;
#endif /* PNG_WRITE_FLUSH_SUPPORTED */
png_ptr->read_data_fn = png_default_read_data;
png_ptr->write_data_fn = png_default_write_data;
#ifdef PNG_WRITE_FLUSH_SUPPORTED
png_ptr->output_flush_fn = png_default_flush;
#endif
}

228
pngmem.c
View File

@ -1,10 +1,10 @@
/* pngmem.c - stub functions for memory allocation
libpng 1.0 beta 2 - version 0.81
libpng 1.0 beta 2 - version 0.85
For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
August 24, 1995
December 19, 1995
This file provides a location for all memory allocation. Users which
need special memory handling are expected to modify the code in this file
@ -19,168 +19,28 @@
need to allocate exactly 64K, so whatever you call here must
have the ability to do that. */
/* Borland compilers have this habit of not giving you 64K chunks
that start on the segment in DOS mode. This has not been observed
in Windows, and of course it doesn't matter in 32 bit mode, as there
are no segments. Now libpng doesn't need that much memory normally,
but zlib does, so we have to normalize it, if necessary. It would be
better if zlib worked in less then 64K, but it doesn't, so we
have to deal with it. Truely, we are misusing farmalloc here,
as it is designed for use with huge pointers, which don't care
about segments. So we allocate a large amount of memory, and
divvy off segments when needed.
*/
#ifdef __TURBOC__
#ifndef __WIN32__
#ifndef __FLAT__
/* NUM_SEG is the number of segments allocated at once */
#define NUM_SEG 4
typedef struct borland_seg_struct
png_voidp
png_large_malloc(png_structp png_ptr, png_uint_32 size)
{
void *mem_ptr;
void *seg_ptr[NUM_SEG];
int seg_used[NUM_SEG];
int num_used;
} borland_seg;
borland_seg *save_array;
int num_save_array;
int max_save_array;
#endif
#endif
#endif
voidpf
png_large_malloc(png_structf *png_ptr, png_uint_32 size)
{
voidpf ret;
png_voidp ret;
if (!png_ptr || !size)
return ((void *)0);
return ((voidp)0);
#ifdef PNG_MAX_MALLOC_64K
if (size > (png_uint_32)65536L)
(*(png_ptr->error_fn))(png_ptr, "Cannot Allocate > 64K");
png_error(png_ptr, "Cannot Allocate > 64K");
#endif
#ifdef __TURBOC__
# if defined(__WIN32__) || defined(__FLAT__)
ret = malloc(size);
# else
if (size == 65536L)
{
unsigned long offset;
if (!save_array)
{
#if defined(__TURBOC__) && !defined(__FLAT__)
ret = farmalloc(size);
offset = (unsigned long)(ret);
offset &= 0xffffL;
}
else
{
ret = (void *)0;
}
if (save_array || offset)
{
int i, j;
if (ret)
farfree(ret);
ret = (void *)0;
if (!save_array)
{
unsigned long offset;
png_byte huge *ptr;
int i;
num_save_array = 1;
save_array = malloc(num_save_array * sizeof (borland_seg));
if (!save_array)
(*(png_ptr->error_fn))(png_ptr, "Out of Memory 1");
save_array->mem_ptr = farmalloc(
(unsigned long)(NUM_SEG) * 65536L + 65532L);
if (!save_array->mem_ptr)
(*(png_ptr->error_fn))(png_ptr, "Out of Memory 2");
offset = (unsigned long)(ret);
offset &= 0xffffL;
ptr = save_array->mem_ptr;
if (offset)
ptr += 65536L - offset;
for (i = 0; i < NUM_SEG; i++, ptr += 65536L)
{
save_array->seg_ptr[i] = ptr;
save_array->seg_used[i] = 0;
}
save_array->num_used = 0;
}
for (i = 0; i < num_save_array; i++)
{
for (j = 0; j < NUM_SEG; j++)
{
if (!save_array[i].seg_used[j])
{
ret = save_array[i].seg_ptr[j];
save_array[i].seg_used[j] = 1;
save_array[i].num_used++;
break;
}
}
if (ret)
break;
}
if (!ret)
{
unsigned long offset;
png_byte huge *ptr;
save_array = realloc(save_array,
(num_save_array + 1) * sizeof (borland_seg));
if (!save_array)
(*(png_ptr->error_fn))(png_ptr, "Out of Memory 3");
save_array[num_save_array].mem_ptr = farmalloc(
(unsigned long)(NUM_SEG) * 65536L + 65532L);
if (!save_array[num_save_array].mem_ptr)
(*(png_ptr->error_fn))(png_ptr, "Out of Memory 4");
offset = (unsigned long)(ret);
offset &= 0xffffL;
ptr = save_array[num_save_array].mem_ptr;
if (offset)
ptr += 65536L - offset;
for (i = 0; i < NUM_SEG; i++, ptr += 65536L)
{
save_array[num_save_array].seg_ptr[i] = ptr;
save_array[num_save_array].seg_used[i] = 0;
}
ret = save_array[num_save_array].seg_ptr[0];
save_array[num_save_array].seg_used[0] = 1;
save_array[num_save_array].num_used = 1;
num_save_array++;
}
}
}
else
{
ret = farmalloc(size);
}
# endif /* __WIN32__ */
#else /* __TURBOC__ */
# ifdef _MSC_VER
ret = halloc(size, 1);
#else
/* everybody else, so normal malloc should do it. */
ret = malloc(size);
# endif
#endif
if (ret == NULL)
{
(*(png_ptr->error_fn))(png_ptr, "Out of Memory");
png_error(png_ptr, "Out of Memory");
}
return ret;
@ -190,83 +50,46 @@ png_large_malloc(png_structf *png_ptr, png_uint_32 size)
configuration, png_ptr is not used, but is passed in case it
is needed. If ptr is NULL, return without taking any action. */
void
png_large_free(png_structf *png_ptr, voidpf ptr)
png_large_free(png_structp png_ptr, png_voidp ptr)
{
if (!png_ptr)
return;
if (ptr != (void *)0)
if (ptr != NULL)
{
#ifdef __TURBOC__
# if defined(__WIN32__) || defined(__FLAT__)
if (ptr)
free(ptr);
# else
int i, j;
for (i = 0; i < num_save_array; i++)
{
for (j = 0; j < NUM_SEG; j++)
{
if (ptr == save_array[i].seg_ptr[j])
{
save_array[i].seg_used[j] = 0;
ptr = 0;
save_array[i].num_used--;
if (!save_array[i].num_used)
{
int k;
num_save_array--;
farfree(save_array[i].mem_ptr);
for (k = i; k < num_save_array; k++)
save_array[k] = save_array[k + 1];
if (!num_save_array)
{
free(save_array);
save_array = 0;
}
}
break;
}
}
if (!ptr)
break;
}
if (ptr)
#if defined(__TURBOC__) && !defined(__FLAT__)
farfree(ptr);
# endif
#else
# ifdef _MSC_VER
hfree(ptr);
#else
free(ptr);
# endif
#endif
}
}
/* Allocate memory. This is called for smallish blocks only It
should not get anywhere near 64K. */
should not get anywhere near 64K. On segmented machines, this
must come from the local heap (for zlib). */
void *
png_malloc(png_struct *png_ptr, png_uint_32 size)
png_malloc(png_structp png_ptr, png_uint_32 size)
{
void *ret;
if (!png_ptr || !size)
{
return ((void *)0);
}
#ifdef PNG_MAX_MALLOC_64K
if (size > (png_uint_32)65536L)
(*(png_ptr->error_fn))(png_ptr, "Cannot Allocate > 64K");
png_error(png_ptr, "Cannot Allocate > 64K");
#endif
ret = malloc((png_size_t)size);
if (!ret)
{
(*(png_ptr->error_fn))(png_ptr, "Out of Memory 6");
png_error(png_ptr, "Out of Memory");
}
return ret;
@ -275,7 +98,7 @@ png_malloc(png_struct *png_ptr, png_uint_32 size)
/* Reallocate memory. This will not get near 64K on a
even marginally reasonable file. */
void *
png_realloc(png_struct *png_ptr, void *ptr, png_uint_32 size,
png_realloc(png_structp png_ptr, void * ptr, png_uint_32 size,
png_uint_32 old_size)
{
void *ret;
@ -285,14 +108,14 @@ png_realloc(png_struct *png_ptr, void *ptr, png_uint_32 size,
#ifdef PNG_MAX_MALLOC_64K
if (size > (png_uint_32)65536L)
(*(png_ptr->error_fn))(png_ptr, "Cannot Allocate > 64K");
png_error(png_ptr, "Cannot Allocate > 64K");
#endif
ret = realloc(ptr, (png_size_t)size);
if (!ret)
{
(*(png_ptr->error_fn))(png_ptr, "Out of Memory 7");
png_error(png_ptr, "Out of Memory 7");
}
return ret;
@ -302,7 +125,7 @@ png_realloc(png_struct *png_ptr, void *ptr, png_uint_32 size,
configuration, png_ptr is not used, but is passed incase it
is needed. If ptr is NULL, return without taking any action. */
void
png_free(png_struct *png_ptr, void *ptr)
png_free(png_structp png_ptr, void * ptr)
{
if (!png_ptr)
return;
@ -311,3 +134,4 @@ png_free(png_struct *png_ptr, void *ptr)
free(ptr);
}

1214
pngpread.c Normal file
View File

File diff suppressed because it is too large Load Diff

60
pngrcb.c
View File

@ -1,16 +1,16 @@
/* pngrcb.c - callbacks while reading a png file
libpng 1.0 beta 2 - version 0.81
libpng 1.0 beta 2 - version 0.85
For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
August 24, 1995
December 19, 1995
*/
#define PNG_INTERNAL
#include "png.h"
void
png_read_IHDR(png_struct *png_ptr, png_info *info,
png_read_IHDR(png_structp png_ptr, png_infop info,
png_uint_32 width, png_uint_32 height, int bit_depth,
int color_type, int compression_type, int filter_type,
int interlace_type)
@ -38,8 +38,8 @@ png_read_IHDR(png_struct *png_ptr, png_info *info,
}
void
png_read_PLTE(png_struct *png_ptr, png_info *info,
png_color *palette, int num)
png_read_PLTE(png_structp png_ptr, png_infop info,
png_colorp palette, int num)
{
if (!png_ptr || !info)
return;
@ -51,7 +51,7 @@ png_read_PLTE(png_struct *png_ptr, png_info *info,
#if defined(PNG_READ_gAMA_SUPPORTED)
void
png_read_gAMA(png_struct *png_ptr, png_info *info, float gamma)
png_read_gAMA(png_structp png_ptr, png_infop info, double gamma)
{
if (!png_ptr || !info)
return;
@ -63,22 +63,22 @@ png_read_gAMA(png_struct *png_ptr, png_info *info, float gamma)
#if defined(PNG_READ_sBIT_SUPPORTED)
void
png_read_sBIT(png_struct *png_ptr, png_info *info,
png_color_8 *sig_bit)
png_read_sBIT(png_structp png_ptr, png_infop info,
png_color_8p sig_bit)
{
if (!png_ptr || !info)
return;
memcpy(&(info->sig_bit), sig_bit, sizeof (png_color_8));
png_memcpy(&(info->sig_bit), sig_bit, sizeof (png_color_8));
info->valid |= PNG_INFO_sBIT;
}
#endif
#if defined(PNG_READ_cHRM_SUPPORTED)
void
png_read_cHRM(png_struct *png_ptr, png_info *info,
float white_x, float white_y, float red_x, float red_y,
float green_x, float green_y, float blue_x, float blue_y)
png_read_cHRM(png_structp png_ptr, png_infop info,
double white_x, double white_y, double red_x, double red_y,
double green_x, double green_y, double blue_x, double blue_y)
{
if (!png_ptr || !info)
return;
@ -97,8 +97,8 @@ png_read_cHRM(png_struct *png_ptr, png_info *info,
#if defined(PNG_READ_tRNS_SUPPORTED)
void
png_read_tRNS(png_struct *png_ptr, png_info *info,
png_byte *trans, int num_trans, png_color_16 *trans_values)
png_read_tRNS(png_structp png_ptr, png_infop info,
png_bytep trans, int num_trans, png_color_16p trans_values)
{
if (!png_ptr || !info)
return;
@ -109,7 +109,7 @@ png_read_tRNS(png_struct *png_ptr, png_info *info,
}
else
{
memcpy(&(info->trans_values), trans_values,
png_memcpy(&(info->trans_values), trans_values,
sizeof(png_color_16));
}
info->num_trans = num_trans;
@ -119,20 +119,20 @@ png_read_tRNS(png_struct *png_ptr, png_info *info,
#if defined(PNG_READ_bKGD_SUPPORTED)
void
png_read_bKGD(png_struct *png_ptr, png_info *info,
png_color_16 *background)
png_read_bKGD(png_structp png_ptr, png_infop info,
png_color_16p background)
{
if (!png_ptr || !info)
return;
memcpy(&(info->background), background, sizeof(png_color_16));
png_memcpy(&(info->background), background, sizeof(png_color_16));
info->valid |= PNG_INFO_bKGD;
}
#endif
#if defined(PNG_READ_hIST_SUPPORTED)
void
png_read_hIST(png_struct *png_ptr, png_info *info, png_uint_16 *hist)
png_read_hIST(png_structp png_ptr, png_infop info, png_uint_16p hist)
{
if (!png_ptr || !info)
return;
@ -144,7 +144,7 @@ png_read_hIST(png_struct *png_ptr, png_info *info, png_uint_16 *hist)
#if defined(PNG_READ_pHYs_SUPPORTED)
void
png_read_pHYs(png_struct *png_ptr, png_info *info,
png_read_pHYs(png_structp png_ptr, png_infop info,
png_uint_32 res_x, png_uint_32 res_y, int unit_type)
{
if (!png_ptr || !info)
@ -159,7 +159,7 @@ png_read_pHYs(png_struct *png_ptr, png_info *info,
#if defined(PNG_READ_oFFs_SUPPORTED)
void
png_read_oFFs(png_struct *png_ptr, png_info *info,
png_read_oFFs(png_structp png_ptr, png_infop info,
png_uint_32 offset_x, png_uint_32 offset_y, int unit_type)
{
if (!png_ptr || !info)
@ -174,21 +174,21 @@ png_read_oFFs(png_struct *png_ptr, png_info *info,
#if defined(PNG_READ_tIME_SUPPORTED)
void
png_read_tIME(png_struct *png_ptr, png_info *info,
png_time *mod_time)
png_read_tIME(png_structp png_ptr, png_infop info,
png_timep mod_time)
{
if (!png_ptr || !info)
return;
memcpy(&(info->mod_time), mod_time, sizeof (png_time));
png_memcpy(&(info->mod_time), mod_time, sizeof (png_time));
info->valid |= PNG_INFO_tIME;
}
#endif
#if defined(PNG_READ_zTXt_SUPPORTED)
void
png_read_zTXt(png_struct *png_ptr, png_info *info,
charf *key, charf *text, png_uint_32 text_len, int compression)
png_read_zTXt(png_structp png_ptr, png_infop info,
png_charp key, png_charp text, png_uint_32 text_len, int compression)
{
if (!png_ptr || !info)
return;
@ -201,7 +201,7 @@ png_read_zTXt(png_struct *png_ptr, png_info *info,
old_max = info->max_text;
info->max_text = info->num_text + 16;
info->text = (png_text *)png_realloc(png_ptr,
info->text = (png_textp)png_realloc(png_ptr,
info->text,
info->max_text * sizeof (png_text),
old_max * sizeof (png_text));
@ -209,7 +209,7 @@ png_read_zTXt(png_struct *png_ptr, png_info *info,
else
{
info->max_text = info->num_text + 16;
info->text = (png_text *)png_malloc(png_ptr,
info->text = (png_textp)png_malloc(png_ptr,
info->max_text * sizeof (png_text));
info->num_text = 0;
}
@ -225,8 +225,8 @@ png_read_zTXt(png_struct *png_ptr, png_info *info,
#if defined(PNG_READ_tEXt_SUPPORTED)
void
png_read_tEXt(png_struct *png_ptr, png_info *info,
charf *key, charf *text, png_uint_32 text_len)
png_read_tEXt(png_structp png_ptr, png_infop info,
png_charp key, png_charp text, png_uint_32 text_len)
{
if (!png_ptr || !info)
return;

234
pngread.c
View File

@ -1,10 +1,10 @@
/* pngread.c - read a png file
libpng 1.0 beta 2 - version 0.81
libpng 1.0 beta 2 - version 0.85
For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
August 24, 1995
December 19, 1995
*/
#define PNG_INTERNAL
@ -12,17 +12,28 @@
/* initialize png structure for reading, and allocate any memory needed */
void
png_read_init(png_struct *png_ptr)
png_read_init(png_structp png_ptr)
{
jmp_buf tmp_jmp;
png_msg_ptr error_fn;
png_msg_ptr warning_fn;
png_voidp msg_ptr;
png_memcpy(tmp_jmp, png_ptr->jmpbuf, sizeof (jmp_buf));
error_fn = png_ptr->error_fn;
warning_fn = png_ptr->warning_fn;
msg_ptr = png_ptr->msg_ptr;
png_memset(png_ptr, 0, sizeof (png_struct));
png_memcpy(png_ptr->jmpbuf, tmp_jmp, sizeof (jmp_buf));
png_ptr->error_fn = error_fn;
png_ptr->warning_fn = warning_fn;
png_ptr->msg_ptr = msg_ptr;
png_ptr->zbuf_size = PNG_ZBUF_SIZE;
png_ptr->zbuf = png_large_malloc(png_ptr, png_ptr->zbuf_size);
png_ptr->zstream = &(png_ptr->zstream_struct);
png_ptr->zstream = (z_stream *)png_malloc(png_ptr, sizeof (z_stream));
png_ptr->zstream->zalloc = png_zalloc;
png_ptr->zstream->zfree = png_zfree;
png_ptr->zstream->opaque = (voidp)png_ptr;
@ -33,35 +44,35 @@ png_read_init(png_struct *png_ptr)
/* read the information before the actual image data. */
void
png_read_info(png_struct *png_ptr, png_info *info)
png_read_info(png_structp png_ptr, png_infop info)
{
png_byte chunk_start[8];
png_uint_32 length;
(*(png_ptr->read_data_fn))(png_ptr, chunk_start, 8);
if (memcmp(chunk_start, png_sig, 8))
(*(png_ptr->error_fn))(png_ptr, "Not a PNG File");
png_read_data(png_ptr, chunk_start, 8);
if (png_memcmp(chunk_start, png_sig, 8))
png_error(png_ptr, "Not a Png File");
while (1)
{
png_uint_32 crc;
(*(png_ptr->read_data_fn))(png_ptr, chunk_start, 8);
png_read_data(png_ptr, chunk_start, 8);
length = png_get_uint_32(chunk_start);
png_reset_crc(png_ptr);
png_calculate_crc(png_ptr, chunk_start + 4, 4);
if (!memcmp(chunk_start + 4, png_IHDR, 4))
if (!png_memcmp(chunk_start + 4, png_IHDR, 4))
{
if (png_ptr->mode != PNG_BEFORE_IHDR)
(*(png_ptr->error_fn))(png_ptr, "Out of Place IHDR");
png_error(png_ptr, "Out of Place IHDR");
png_handle_IHDR(png_ptr, info, length);
png_ptr->mode = PNG_HAVE_IHDR;
}
else if (!memcmp(chunk_start + 4, png_PLTE, 4))
else if (!png_memcmp(chunk_start + 4, png_PLTE, 4))
{
if (png_ptr->mode != PNG_HAVE_IHDR)
(*(png_ptr->error_fn))(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)
@ -74,118 +85,118 @@ png_read_info(png_struct *png_ptr, png_info *info)
#endif
png_ptr->mode = PNG_HAVE_PLTE;
}
else if (!memcmp(chunk_start + 4, png_IDAT, 4))
else if (!png_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))
else if (!png_memcmp(chunk_start + 4, png_IEND, 4))
{
(*(png_ptr->error_fn))(png_ptr, "No Image in File");
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 (!png_memcmp(chunk_start + 4, png_gAMA, 4))
{
if (png_ptr->mode != PNG_HAVE_IHDR)
(*(png_ptr->error_fn))(png_ptr, "Out of Place PLTE");
png_error(png_ptr, "Out of Place PLTE");
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 (!png_memcmp(chunk_start + 4, png_sBIT, 4))
{
if (png_ptr->mode != PNG_HAVE_IHDR)
(*(png_ptr->error_fn))(png_ptr, "Out of Place sBIT");
png_error(png_ptr, "Out of Place sBIT");
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 (!png_memcmp(chunk_start + 4, png_cHRM, 4))
{
if (png_ptr->mode != PNG_HAVE_IHDR)
(*(png_ptr->error_fn))(png_ptr, "Out of Place cHRM");
png_error(png_ptr, "Out of Place cHRM");
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 (!png_memcmp(chunk_start + 4, png_tRNS, 4))
{
if (png_ptr->mode != PNG_HAVE_IHDR &&
png_ptr->mode != PNG_HAVE_PLTE)
(*(png_ptr->error_fn))(png_ptr, "Out of Place tRNS");
png_error(png_ptr, "Out of Place tRNS");
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 (!png_memcmp(chunk_start + 4, png_bKGD, 4))
{
if (png_ptr->mode != PNG_HAVE_IHDR &&
png_ptr->mode != PNG_HAVE_PLTE)
(*(png_ptr->error_fn))(png_ptr, "Out of Place bKGD");
png_error(png_ptr, "Out of Place bKGD");
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 (!png_memcmp(chunk_start + 4, png_hIST, 4))
{
if (png_ptr->mode != PNG_HAVE_PLTE)
(*(png_ptr->error_fn))(png_ptr, "Out of Place hIST");
png_error(png_ptr, "Out of Place hIST");
png_handle_hIST(png_ptr, info, length);
}
#endif
#if defined(PNG_READ_pHYs_SUPPORTED)
else if (!memcmp(chunk_start + 4, png_pHYs, 4))
else if (!png_memcmp(chunk_start + 4, png_pHYs, 4))
{
if (png_ptr->mode != PNG_HAVE_IHDR &&
png_ptr->mode != PNG_HAVE_PLTE)
(*(png_ptr->error_fn))(png_ptr, "Out of Place pHYs");
png_error(png_ptr, "Out of Place pHYs");
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 (!png_memcmp(chunk_start + 4, png_oFFs, 4))
{
if (png_ptr->mode != PNG_HAVE_IHDR &&
png_ptr->mode != PNG_HAVE_PLTE)
(*(png_ptr->error_fn))(png_ptr, "Out of Place oFFs");
png_error(png_ptr, "Out of Place oFFs");
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 (!png_memcmp(chunk_start + 4, png_tIME, 4))
{
if (png_ptr->mode == PNG_BEFORE_IHDR ||
png_ptr->mode == PNG_AFTER_IEND)
(*(png_ptr->error_fn))(png_ptr, "Out of Place tIME");
png_error(png_ptr, "Out of Place tIME");
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 (!png_memcmp(chunk_start + 4, png_tEXt, 4))
{
if (png_ptr->mode == PNG_BEFORE_IHDR ||
png_ptr->mode == PNG_AFTER_IEND)
(*(png_ptr->error_fn))(png_ptr, "Out of Place tEXt");
png_error(png_ptr, "Out of Place tEXt");
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 (!png_memcmp(chunk_start + 4, png_zTXt, 4))
{
if (png_ptr->mode == PNG_BEFORE_IHDR ||
png_ptr->mode == PNG_AFTER_IEND)
(*(png_ptr->error_fn))(png_ptr, "Out of Place zTXt");
png_error(png_ptr, "Out of Place zTXt");
png_handle_zTXt(png_ptr, info, length);
}
@ -193,21 +204,21 @@ png_read_info(png_struct *png_ptr, png_info *info)
else
{
if ((chunk_start[4] & 0x20) == 0)
(*(png_ptr->error_fn))(png_ptr, "Unknown Critical Chunk");
png_error(png_ptr, "Unknown Critical Chunk");
png_crc_skip(png_ptr, length);
}
(*(png_ptr->read_data_fn))(png_ptr, chunk_start, 4);
png_read_data(png_ptr, chunk_start, 4);
crc = png_get_uint_32(chunk_start);
if (((crc ^ 0xffffffffL) & 0xffffffffL) !=
(png_ptr->crc & 0xffffffffL))
(*(png_ptr->error_fn))(png_ptr, "Bad CRC value");
png_error(png_ptr, "Bad CRC value");
}
}
/* optional call to update the users info structure */
void
png_read_update_info(png_struct *png_ptr, png_info *info_ptr)
png_read_update_info(png_structp png_ptr, png_infop info_ptr)
{
if (!(png_ptr->row_init))
png_read_start_row(png_ptr);
@ -219,14 +230,14 @@ png_read_update_info(png_struct *png_ptr, png_info *info_ptr)
the user to obtail a gamma corrected palette, for example.
If the user doesn't call this, we will do it ourselves. */
void
png_start_read_image(png_struct *png_ptr)
png_start_read_image(png_structp png_ptr)
{
if (!(png_ptr->row_init))
png_read_start_row(png_ptr);
}
void
png_read_row(png_struct *png_ptr, png_bytef *row, png_byte *dsp_row)
png_read_row(png_structp png_ptr, png_bytep row, png_bytep dsp_row)
{
int ret;
if (!(png_ptr->row_init))
@ -310,7 +321,7 @@ png_read_row(png_struct *png_ptr, png_bytef *row, png_byte *dsp_row)
#endif
if (png_ptr->mode != PNG_HAVE_IDAT)
(*(png_ptr->error_fn))(png_ptr, "Invalid attempt to read row data");
png_error(png_ptr, "invalid attempt to read row data");
png_ptr->zstream->next_out = png_ptr->row_buf;
png_ptr->zstream->avail_out = (uInt)png_ptr->irowbytes;
@ -323,19 +334,19 @@ png_read_row(png_struct *png_ptr, png_bytef *row, png_byte *dsp_row)
png_byte buf[4];
png_uint_32 crc;
(*(png_ptr->read_data_fn))(png_ptr, buf, 4);
png_read_data(png_ptr, buf, 4);
crc = png_get_uint_32(buf);
if (((crc ^ 0xffffffffL) & 0xffffffffL) !=
(png_ptr->crc & 0xffffffffL))
(*(png_ptr->error_fn))(png_ptr, "Bad CRC value");
png_error(png_ptr, "Bad CRC value");
(*(png_ptr->read_data_fn))(png_ptr, buf, 4);
png_read_data(png_ptr, buf, 4);
png_ptr->idat_size = png_get_uint_32(buf);
png_reset_crc(png_ptr);
png_crc_read(png_ptr, buf, 4);
if (memcmp(buf, png_IDAT, 4))
(*(png_ptr->error_fn))(png_ptr, "Not enough image data");
if (png_memcmp(buf, png_IDAT, 4))
png_error(png_ptr, "Not enough image data");
}
png_ptr->zstream->avail_in = (uInt)png_ptr->zbuf_size;
@ -350,12 +361,12 @@ png_read_row(png_struct *png_ptr, png_bytef *row, png_byte *dsp_row)
{
if (png_ptr->zstream->avail_out || png_ptr->zstream->avail_in ||
png_ptr->idat_size)
(*(png_ptr->warning_fn))(png_ptr, "Extra compressed data");
png_error(png_ptr, "Extra compressed data");
png_ptr->mode = PNG_AT_LAST_IDAT;
break;
}
if (ret != Z_OK)
(*(png_ptr->error_fn))(png_ptr, "Compression Error");
png_error(png_ptr, "Compression Error");
} while (png_ptr->zstream->avail_out);
@ -425,20 +436,21 @@ png_read_row(png_struct *png_ptr, png_bytef *row, png_byte *dsp_row)
also, but you may. If the image is not interlaced, or if you have
not called png_set_interlace_handling(), the display_row buffer will
be ignored, so pass NULL to it. */
void
png_read_rows(png_struct *png_ptr, png_bytef **row,
png_byte **display_row, png_uint_32 num_rows)
png_read_rows(png_structp png_ptr, png_bytepp row,
png_bytepp display_row, png_uint_32 num_rows)
{
png_uint_32 i;
png_bytef **rp;
png_byte **dp;
png_bytepp rp;
png_bytepp dp;
rp = row;
dp = display_row;
for (i = 0; i < num_rows; i++)
{
png_bytef *rptr;
png_byte *dptr;
png_bytep rptr;
png_bytep dptr;
if (rp)
rptr = *rp;
@ -448,7 +460,6 @@ png_read_rows(png_struct *png_ptr, png_bytef **row,
dptr = *dp;
else
dptr = NULL;
png_read_row(png_ptr, rptr, dptr);
if (row)
rp++;
@ -464,11 +475,11 @@ png_read_rows(png_struct *png_ptr, png_bytef **row,
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() */
void
png_read_image(png_struct *png_ptr, png_bytef **image)
png_read_image(png_structp png_ptr, png_bytepp image)
{
png_uint_32 i;
int pass, j;
png_bytef **rp;
png_bytepp rp;
pass = png_set_interlace_handling(png_ptr);
for (j = 0; j < pass; j++)
@ -486,76 +497,76 @@ png_read_image(png_struct *png_ptr, png_bytef **image)
file, will verify the end is accurate, and will read any comments
or time information at the end of the file, if info is not NULL. */
void
png_read_end(png_struct *png_ptr, png_info *info)
png_read_end(png_structp png_ptr, png_infop info)
{
png_byte chunk_start[8];
png_uint_32 length;
png_uint_32 crc;
(*(png_ptr->read_data_fn))(png_ptr, chunk_start, 4);
png_read_data(png_ptr, chunk_start, 4);
crc = png_get_uint_32(chunk_start);
if (((crc ^ 0xffffffffL) & 0xffffffffL) !=
(png_ptr->crc & 0xffffffffL))
(*(png_ptr->error_fn))(png_ptr, "Bad CRC value");
png_error(png_ptr, "Bad CRC value");
do
{
(*(png_ptr->read_data_fn))(png_ptr, chunk_start, 8);
png_read_data(png_ptr, chunk_start, 8);
length = png_get_uint_32(chunk_start);
png_reset_crc(png_ptr);
png_calculate_crc(png_ptr, chunk_start + 4, 4);
if (!memcmp(chunk_start + 4, png_IHDR, 4))
if (!png_memcmp(chunk_start + 4, png_IHDR, 4))
{
(*(png_ptr->error_fn))(png_ptr, "Invalid chunk after IDAT");
png_error(png_ptr, "invalid chunk after IDAT");
}
else if (!memcmp(chunk_start + 4, png_PLTE, 4))
else if (!png_memcmp(chunk_start + 4, png_PLTE, 4))
{
(*(png_ptr->error_fn))(png_ptr, "Invalid chunk after IDAT");
png_error(png_ptr, "invalid chunk after IDAT");
}
else if (!memcmp(chunk_start + 4, png_gAMA, 4))
else if (!png_memcmp(chunk_start + 4, png_gAMA, 4))
{
(*(png_ptr->error_fn))(png_ptr, "Invalid chunk after IDAT");
png_error(png_ptr, "invalid chunk after IDAT");
}
else if (!memcmp(chunk_start + 4, png_sBIT, 4))
else if (!png_memcmp(chunk_start + 4, png_sBIT, 4))
{
(*(png_ptr->error_fn))(png_ptr, "Invalid chunk after IDAT");
png_error(png_ptr, "invalid chunk after IDAT");
}
else if (!memcmp(chunk_start + 4, png_cHRM, 4))
else if (!png_memcmp(chunk_start + 4, png_cHRM, 4))
{
(*(png_ptr->error_fn))(png_ptr, "Invalid chunk after IDAT");
png_error(png_ptr, "invalid chunk after IDAT");
}
else if (!memcmp(chunk_start + 4, png_tRNS, 4))
else if (!png_memcmp(chunk_start + 4, png_tRNS, 4))
{
(*(png_ptr->error_fn))(png_ptr, "Invalid chunk after IDAT");
png_error(png_ptr, "invalid chunk after IDAT");
}
else if (!memcmp(chunk_start + 4, png_bKGD, 4))
else if (!png_memcmp(chunk_start + 4, png_bKGD, 4))
{
(*(png_ptr->error_fn))(png_ptr, "Invalid chunk after IDAT");
png_error(png_ptr, "invalid chunk after IDAT");
}
else if (!memcmp(chunk_start + 4, png_hIST, 4))
else if (!png_memcmp(chunk_start + 4, png_hIST, 4))
{
(*(png_ptr->error_fn))(png_ptr, "Invalid chunk after IDAT");
png_error(png_ptr, "invalid chunk after IDAT");
}
else if (!memcmp(chunk_start + 4, png_IDAT, 4))
else if (!png_memcmp(chunk_start + 4, png_IDAT, 4))
{
if (length > 0 || png_ptr->mode != PNG_AT_LAST_IDAT)
(*(png_ptr->error_fn))(png_ptr, "Too many IDAT's found");
png_error(png_ptr, "too many IDAT's found");
}
else if (!memcmp(chunk_start + 4, png_pHYs, 4))
else if (!png_memcmp(chunk_start + 4, png_pHYs, 4))
{
(*(png_ptr->error_fn))(png_ptr, "Invalid chunk after IDAT");
png_error(png_ptr, "invalid chunk after IDAT");
}
else if (!memcmp(chunk_start + 4, png_oFFs, 4))
else if (!png_memcmp(chunk_start + 4, png_oFFs, 4))
{
(*(png_ptr->error_fn))(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 (!png_memcmp(chunk_start + 4, png_tIME, 4))
{
if (png_ptr->mode == PNG_BEFORE_IHDR ||
png_ptr->mode == PNG_AFTER_IEND)
(*(png_ptr->error_fn))(png_ptr, "Out of Place tIME");
png_error(png_ptr, "Out of Place tIME");
if (info)
png_handle_tIME(png_ptr, info, length);
@ -564,11 +575,11 @@ png_read_end(png_struct *png_ptr, png_info *info)
}
#endif
#if defined(PNG_READ_tEXt_SUPPORTED)
else if (!memcmp(chunk_start + 4, png_tEXt, 4))
else if (!png_memcmp(chunk_start + 4, png_tEXt, 4))
{
if (png_ptr->mode == PNG_BEFORE_IHDR ||
png_ptr->mode == PNG_AFTER_IEND)
(*(png_ptr->error_fn))(png_ptr, "Out of Place tEXt");
png_error(png_ptr, "Out of Place tEXt");
if (info)
png_handle_tEXt(png_ptr, info, length);
@ -577,11 +588,11 @@ png_read_end(png_struct *png_ptr, png_info *info)
}
#endif
#if defined(PNG_READ_zTXt_SUPPORTED)
else if (!memcmp(chunk_start + 4, png_zTXt, 4))
else if (!png_memcmp(chunk_start + 4, png_zTXt, 4))
{
if (png_ptr->mode == PNG_BEFORE_IHDR ||
png_ptr->mode == PNG_AFTER_IEND)
(*(png_ptr->error_fn))(png_ptr, "Out of Place zTXt");
png_error(png_ptr, "Out of Place zTXt");
if (info)
png_handle_zTXt(png_ptr, info, length);
@ -589,31 +600,22 @@ png_read_end(png_struct *png_ptr, png_info *info)
png_crc_skip(png_ptr, length);
}
#endif
else if (!memcmp(chunk_start + 4, png_IEND, 4))
else if (!png_memcmp(chunk_start + 4, png_IEND, 4))
{
png_ptr->mode = PNG_AFTER_IEND;
}
else
{
char msg[80];
if ((chunk_start[4] & 0x20) == 0)
{
png_strcpy(msg,"Unknown critical chunk ");
png_memcpy(msg + strlen(msg), chunk_start + 4,4);
(*(png_ptr->error_fn))(png_ptr, msg);
}
png_error(png_ptr, "Unknown Critical Chunk");
png_strcpy(msg,"Unknown extension chunk ");
png_memcpy(msg + strlen(msg), chunk_start + 4,4);
(*(png_ptr->warning_fn))(png_ptr, msg);
png_crc_skip(png_ptr, length);
}
(*(png_ptr->read_data_fn))(png_ptr, chunk_start, 4);
png_read_data(png_ptr, chunk_start, 4);
crc = png_get_uint_32(chunk_start);
if (((crc ^ 0xffffffffL) & 0xffffffffL) !=
(png_ptr->crc & 0xffffffffL))
(*(png_ptr->error_fn))(png_ptr, "Bad CRC value");
png_error(png_ptr, "Bad CRC value");
if (png_ptr->mode == PNG_AT_LAST_IDAT)
png_ptr->mode = PNG_AFTER_IDAT;
} while (png_ptr->mode != PNG_AFTER_IEND);
@ -621,7 +623,7 @@ png_read_end(png_struct *png_ptr, png_info *info)
/* free all memory used by the read */
void
png_read_destroy(png_struct *png_ptr, png_info *info, png_info *end_info)
png_read_destroy(png_structp png_ptr, png_infop info, png_infop end_info)
{
int i;
jmp_buf tmp_jmp;
@ -630,17 +632,14 @@ png_read_destroy(png_struct *png_ptr, png_info *info, png_info *end_info)
{
if (png_ptr->do_free & PNG_FREE_PALETTE)
png_free(png_ptr, info->palette);
#if defined(PNG_READ_BACKGROUND_SUPPORTED) && defined(PNG_READ_bKGD_SUPPORTED)
if (png_ptr->do_free & PNG_FREE_TRANS)
if (png_ptr->do_free & PNG_FREE_PALETTE)
png_free(png_ptr, info->trans);
#endif
#if defined(PNG_READ_hIST_SUPPORTED)
if (png_ptr->do_free & PNG_FREE_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++)
{
@ -668,21 +667,17 @@ png_read_destroy(png_struct *png_ptr, png_info *info, png_info *end_info)
png_large_free(png_ptr, png_ptr->zbuf);
png_large_free(png_ptr, png_ptr->row_buf);
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_free(png_ptr, png_ptr->dither_index);
#endif
#if defined(PNG_READ_GAMMA_SUPPORTED)
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_to_1);
#endif
#if defined(PNG_READ_GAMMA_SUPPORTED)
if (png_ptr->gamma_16_table)
{
@ -692,7 +687,6 @@ png_read_destroy(png_struct *png_ptr, png_info *info, png_info *end_info)
}
}
#endif
#if defined(PNG_READ_BACKGROUND_SUPPORTED)
png_free(png_ptr, png_ptr->gamma_16_table);
if (png_ptr->gamma_16_from_1)
@ -712,20 +706,20 @@ png_read_destroy(png_struct *png_ptr, png_info *info, png_info *end_info)
}
png_free(png_ptr, png_ptr->gamma_16_to_1);
#endif
#if defined(PNG_READ_BACKGROUND_SUPPORTED)
png_free(png_ptr, png_ptr->trans);
#endif
#if defined(PNG_READ_DITHER_SUPPORTED)
png_free(png_ptr, png_ptr->hist);
#endif
if (!png_ptr->user_palette)
png_free(png_ptr, png_ptr->palette);
inflateEnd(png_ptr->zstream);
png_free(png_ptr, png_ptr->zstream);
#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
png_free(png_ptr, png_ptr->save_buffer);
#endif
png_memcpy(tmp_jmp, png_ptr->jmpbuf, sizeof (jmp_buf));
png_memset(png_ptr, 0, sizeof (png_struct));
png_memcpy(png_ptr->jmpbuf, tmp_jmp, sizeof (jmp_buf));

239
pngrtran.c
View File

@ -1,10 +1,10 @@
/* pngrtran.c - transforms the data in a row for png readers
libpng 1.0 beta 2 - version 0.8
libpng 1.0 beta 2 - version 0.85
For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
August 20, 1995
December 19, 1995
*/
#define PNG_INTERNAL
@ -13,8 +13,8 @@
#if defined(PNG_READ_BACKGROUND_SUPPORTED)
/* handle alpha and tRNS via a background color */
void
png_set_background(png_struct *png_ptr,
png_color_16 *background_color, int background_gamma_code,
png_set_background(png_structp png_ptr,
png_color_16p background_color, int background_gamma_code,
int need_expand, double background_gamma)
{
png_ptr->transformations |= PNG_BACKGROUND;
@ -29,7 +29,7 @@ png_set_background(png_struct *png_ptr,
#if defined(PNG_READ_16_TO_8_SUPPORTED)
/* strip 16 bit depth files to 8 bit depth */
void
png_set_strip_16(png_struct *png_ptr)
png_set_strip_16(png_structp png_ptr)
{
png_ptr->transformations |= PNG_16_TO_8;
}
@ -42,16 +42,19 @@ png_set_strip_16(png_struct *png_ptr)
is greater then the maximum number, the palette will be
modified to fit in the maximum number */
typedef struct dsort_struct
typedef struct png_dsort_struct
{
struct dsort_struct *next;
struct png_dsort_struct FAR * next;
png_byte left;
png_byte right;
} dsort;
} png_dsort;
typedef png_dsort FAR * png_dsortp;
typedef png_dsort FAR * FAR * png_dsortpp;
void
png_set_dither(png_struct *png_ptr, png_color *palette,
int num_palette, int maximum_colors, png_uint_16 *histogram,
png_set_dither(png_structp png_ptr, png_colorp palette,
int num_palette, int maximum_colors, png_uint_16p histogram,
int full_dither)
{
png_ptr->transformations |= PNG_DITHER;
@ -60,7 +63,7 @@ png_set_dither(png_struct *png_ptr, png_color *palette,
{
int i;
png_ptr->dither_index = png_malloc(png_ptr,
png_ptr->dither_index = (png_bytep)png_malloc(png_ptr,
num_palette * sizeof (png_byte));
for (i = 0; i < num_palette; i++)
png_ptr->dither_index[i] = i;
@ -74,10 +77,10 @@ png_set_dither(png_struct *png_ptr, png_color *palette,
perhaps not the best solution, but good enough */
int i;
png_byte *sort;
png_bytep sort;
/* initialize an array to sort colors */
sort = (png_byte *)png_malloc(png_ptr, num_palette * sizeof (png_byte));
sort = (png_bytep)png_malloc(png_ptr, num_palette * sizeof (png_byte));
/* initialize the sort array */
for (i = 0; i < num_palette; i++)
@ -200,16 +203,16 @@ png_set_dither(png_struct *png_ptr, png_color *palette,
int i;
int max_d;
int num_new_palette;
dsort **hash;
png_byte *index_to_palette;
png_dsortpp hash;
png_bytep index_to_palette;
/* where the original index currently is in the palette */
png_byte *palette_to_index;
png_bytep palette_to_index;
/* which original index points to this palette color */
/* initialize palette index arrays */
index_to_palette = (png_byte *)png_malloc(png_ptr,
index_to_palette = (png_bytep)png_malloc(png_ptr,
num_palette * sizeof (png_byte));
palette_to_index = (png_byte *)png_malloc(png_ptr,
palette_to_index = (png_bytep)png_malloc(png_ptr,
num_palette * sizeof (png_byte));
/* initialize the sort array */
@ -219,10 +222,10 @@ png_set_dither(png_struct *png_ptr, png_color *palette,
palette_to_index[i] = i;
}
hash = (dsort **)png_malloc(png_ptr, 769 * sizeof (dsort *));
hash = (png_dsortpp)png_malloc(png_ptr, 769 * sizeof (png_dsortp));
for (i = 0; i < 769; i++)
hash[i] = (dsort *)0;
/* png_memset(hash, 0, 769 * sizeof (dsort *)); */
hash[i] = (png_dsortp)0;
/* png_memset(hash, 0, 769 * sizeof (png_dsortp)); */
num_new_palette = num_palette;
@ -250,9 +253,9 @@ png_set_dither(png_struct *png_ptr, png_color *palette,
if (d <= max_d)
{
dsort *t;
png_dsortp t;
t = png_malloc(png_ptr, sizeof (dsort));
t = png_malloc(png_ptr, sizeof (png_dsort));
t->next = hash[d];
t->left = i;
t->right = j;
@ -265,7 +268,7 @@ png_set_dither(png_struct *png_ptr, png_color *palette,
{
if (hash[i])
{
dsort *p;
png_dsortp p;
for (p = hash[i]; p; p = p->next)
{
@ -325,12 +328,12 @@ png_set_dither(png_struct *png_ptr, png_color *palette,
{
if (hash[i])
{
dsort *p;
png_dsortp p;
p = hash[i];
while (p)
{
dsort *t;
png_dsortp t;
t = p->next;
png_free(png_ptr, p);
@ -359,7 +362,7 @@ png_set_dither(png_struct *png_ptr, png_color *palette,
int i;
int total_bits, num_red, num_green, num_blue;
png_uint_32 num_entries;
png_bytef *distance;
png_bytep distance;
total_bits = PNG_DITHER_RED_BITS + PNG_DITHER_GREEN_BITS +
PNG_DITHER_BLUE_BITS;
@ -369,12 +372,12 @@ png_set_dither(png_struct *png_ptr, png_color *palette,
num_blue = (1 << PNG_DITHER_BLUE_BITS);
num_entries = ((png_uint_32)1 << total_bits);
png_ptr->palette_lookup = (png_bytef *)png_large_malloc(png_ptr,
png_ptr->palette_lookup = (png_bytep )png_large_malloc(png_ptr,
(png_size_t)num_entries * sizeof (png_byte));
png_memset(png_ptr->palette_lookup, 0, (png_size_t)num_entries * sizeof (png_byte));
distance = (png_bytef *)png_large_malloc(png_ptr,
distance = (png_bytep )png_large_malloc(png_ptr,
(png_size_t)num_entries * sizeof (png_byte));
png_memset(distance, 0xff, (png_size_t)num_entries * sizeof (png_byte));
@ -428,7 +431,7 @@ png_set_dither(png_struct *png_ptr, png_color *palette,
#if defined(PNG_READ_GAMMA_SUPPORTED)
/* transform the image from the file_gamma to the screen_gamma */
void
png_set_gamma(png_struct *png_ptr, double screen_gamma,
png_set_gamma(png_structp png_ptr, double screen_gamma,
double file_gamma)
{
png_ptr->transformations |= PNG_GAMMA;
@ -442,7 +445,7 @@ png_set_gamma(png_struct *png_ptr, double screen_gamma,
less then 8 bit depth to 8 bit depth, and expand tRNS chunks
to alpha channels */
void
png_set_expand(png_struct *png_ptr)
png_set_expand(png_structp png_ptr)
{
png_ptr->transformations |= PNG_EXPAND;
}
@ -450,7 +453,7 @@ png_set_expand(png_struct *png_ptr)
#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
void
png_set_gray_to_rgb(png_struct *png_ptr)
png_set_gray_to_rgb(png_structp png_ptr)
{
png_ptr->transformations |= PNG_GRAY_TO_RGB;
}
@ -459,7 +462,7 @@ png_set_gray_to_rgb(png_struct *png_ptr)
/* initialize everything needed for the read. This includes modifying
the palette */
void
png_init_read_transformations(png_struct *png_ptr)
png_init_read_transformations(png_structp png_ptr)
{
int color_type;
@ -523,7 +526,7 @@ png_init_read_transformations(png_struct *png_ptr)
{
double g, gs, m;
m = (double)((png_uint_32)1 << png_ptr->bit_depth);
m = (double)(((png_uint_32)1 << png_ptr->bit_depth) - 1);
g = 1.0;
gs = 1.0;
@ -544,7 +547,7 @@ png_init_read_transformations(png_struct *png_ptr)
break;
}
if (png_ptr->color_type & PNG_COLOR_MASK_COLOR)
if (color_type & PNG_COLOR_MASK_COLOR)
{
png_ptr->background_1.red = (png_uint_16)(pow(
(double)png_ptr->background.red / m, g) * m + .5);
@ -572,9 +575,9 @@ png_init_read_transformations(png_struct *png_ptr)
}
#endif
#if defined(PNG_READ_SHIFT_SUPPORTED) && defined(PNG_READ_sBIT_SUPPORTED)
#if defined(PNG_READ_SHIFT_SUPPORTED)
if ((png_ptr->transformations & PNG_SHIFT) &&
png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
color_type == PNG_COLOR_TYPE_PALETTE)
{
png_uint_16 i;
int sr, sg, sb;
@ -602,7 +605,7 @@ png_init_read_transformations(png_struct *png_ptr)
info should be updated so a png file could be written with it,
assuming the transformations result in valid png data */
void
png_read_transform_info(png_struct *png_ptr, png_info *info_ptr)
png_read_transform_info(png_structp png_ptr, png_infop info_ptr)
{
#if defined(PNG_READ_EXPAND_SUPPORTED)
if ((png_ptr->transformations & PNG_EXPAND) &&
@ -677,7 +680,7 @@ png_read_transform_info(png_struct *png_ptr, png_info *info_ptr)
and is very touchy. If you add a transformation, take care to
decide how it fits in with the other transformations here */
void
png_do_read_transformations(png_struct *png_ptr)
png_do_read_transformations(png_structp png_ptr)
{
#if defined(PNG_READ_EXPAND_SUPPORTED)
if ((png_ptr->transformations & PNG_EXPAND) &&
@ -724,7 +727,7 @@ png_do_read_transformations(png_struct *png_ptr)
#if defined(PNG_READ_DITHER_SUPPORTED)
if (png_ptr->transformations & PNG_DITHER)
{
png_do_dither((png_row_info *)&(png_ptr->row_info),
png_do_dither((png_row_infop)&(png_ptr->row_info),
png_ptr->row_buf + 1,
png_ptr->palette_lookup,
png_ptr->dither_index);
@ -776,10 +779,10 @@ png_do_read_transformations(png_struct *png_ptr)
the numbers 0 or 1. If you would rather they contain 0 and 255, use
png_do_shift() after this. */
void
png_do_unpack(png_row_info *row_info, png_bytef *row)
png_do_unpack(png_row_infop row_info, png_bytep row)
{
int shift;
png_bytef *sp, *dp;
png_bytep sp, dp;
png_uint_32 i;
if (row && row_info && row_info->bit_depth < 8)
@ -831,7 +834,7 @@ png_do_unpack(png_row_info *row_info, png_bytef *row)
{
sp = row + (png_size_t)((row_info->width - 1) >> 1);
dp = row + (png_size_t)row_info->width - 1;
shift = (int)((1 - ((row_info->width + 1) & 1)) << 4);
shift = (int)((1 - ((row_info->width + 1) & 1)) << 2);
for (i = 0; i < row_info->width; i++)
{
*dp = (*sp >> shift) & 0xf;
@ -861,10 +864,10 @@ png_do_unpack(png_row_info *row_info, png_bytef *row)
a row of bit depth 8, but only 5 are significant, this will shift
the values back to 0 through 31 */
void
png_do_unshift(png_row_info *row_info, png_bytef *row,
png_color_8 *sig_bits)
png_do_unshift(png_row_infop row_info, png_bytep row,
png_color_8p sig_bits)
{
png_bytef *bp;
png_bytep bp;
png_uint_16 value;
png_uint_32 i;
if (row && row_info && sig_bits &&
@ -876,32 +879,31 @@ png_do_unshift(png_row_info *row_info, png_bytef *row,
channels = 0;
if (row_info->color_type & PNG_COLOR_MASK_COLOR)
{
shift[channels++] = row_info->bit_depth - sig_bits->red < 0 ?
0 : row_info->bit_depth - sig_bits->red;
shift[channels++] = row_info->bit_depth - sig_bits->green < 0 ?
0 : row_info->bit_depth - sig_bits->green;
shift[channels++] = row_info->bit_depth - sig_bits->blue < 0 ?
0 : row_info->bit_depth - sig_bits->blue;
shift[channels++] = row_info->bit_depth - sig_bits->red;
shift[channels++] = row_info->bit_depth - sig_bits->green;
shift[channels++] = row_info->bit_depth - sig_bits->blue;
}
else
{
shift[channels++] = row_info->bit_depth - sig_bits->gray < 0 ?
0 : row_info->bit_depth - sig_bits->gray;
shift[channels++] = row_info->bit_depth - sig_bits->gray;
}
if (row_info->color_type & PNG_COLOR_MASK_ALPHA)
{
shift[channels++] = row_info->bit_depth - sig_bits->alpha < 0 ?
0 : row_info->bit_depth - sig_bits->alpha;
shift[channels++] = row_info->bit_depth - sig_bits->alpha;
}
value = 1;
value = 0;
for (i = 0; i < channels; i++)
{
if (shift[i] != 0) value = 0;
if (shift[i] <= 0)
shift[i] = 0;
else
value = 1;
}
if (value == 1) return;
if (!value)
return;
switch (row_info->bit_depth)
{
@ -919,7 +921,6 @@ png_do_unshift(png_row_info *row_info, png_bytef *row,
case 4:
{
png_byte mask;
mask = (png_byte)(((int)0xf0 >> shift[0]) & (int)0xf0) |
((int)0xf >> shift[0]);
for (bp = row, i = 0;
@ -970,17 +971,24 @@ png_do_unshift(png_row_info *row_info, png_bytef *row,
#if defined(PNG_READ_16_TO_8_SUPPORTED)
/* chop rows of bit depth 16 down to 8 */
void
png_do_chop(png_row_info *row_info, png_bytef *row)
png_do_chop(png_row_infop row_info, png_bytep row)
{
png_bytep sp, dp;
png_uint_32 i;
if (row && row_info && row_info->bit_depth == 16)
{
png_bytef *sp = row, *dp = row;
png_uint_32 i;
sp = row;
dp = row;
for (i = 0; i < row_info->width * row_info->channels; i++)
{
*dp++ = ((((*sp << 8 | *(sp + 1)) - *sp) + 0x7F) >> 8) & 0xFF;
*dp = *sp;
/* not yet, as I'm afraid of overflow here
*dp = ((((((png_uint_16)(*sp) << 8)) |
(png_uint_16)((*(sp + 1) - *sp) & 0xff) +
0x7f) >> 8) & 0xff);
*/
sp += 2;
dp++;
}
row_info->bit_depth = 8;
row_info->pixel_depth = 8 * row_info->channels;
@ -992,10 +1000,10 @@ png_do_chop(png_row_info *row_info, png_bytef *row)
#if defined(PNG_READ_FILLER_SUPPORTED)
/* add filler byte */
void
png_do_read_filler(png_row_info *row_info, png_bytef *row,
png_do_read_filler(png_row_infop row_info, png_bytep row,
png_byte filler, png_byte filler_loc)
{
png_bytef *sp, *dp;
png_bytep sp, dp;
png_uint_32 i;
if (row && row_info && row_info->color_type == 2 &&
row_info->bit_depth == 8)
@ -1040,10 +1048,11 @@ png_do_read_filler(png_row_info *row_info, png_bytef *row,
#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
/* expand grayscale files to rgb, with or without alpha */
void
png_do_gray_to_rgb(png_row_info *row_info, png_bytef *row)
png_do_gray_to_rgb(png_row_infop row_info, png_bytep row)
{
png_bytef *sp, *dp;
png_bytep sp, dp;
png_uint_32 i;
if (row && row_info && row_info->bit_depth >= 8 &&
!(row_info->color_type & PNG_COLOR_MASK_COLOR))
{
@ -1130,7 +1139,7 @@ png_do_gray_to_rgb(png_row_info *row_info, png_bytef *row)
paletted. Most useful for gamma correction and simplification
of code. */
void
png_build_grayscale_palette(int bit_depth, png_color *palette)
png_build_grayscale_palette(int bit_depth, png_colorp palette)
{
int num_palette;
int color_inc;
@ -1160,7 +1169,6 @@ png_build_grayscale_palette(int bit_depth, png_color *palette)
break;
default:
num_palette = 0;
color_inc = 0;
break;
}
@ -1174,7 +1182,7 @@ png_build_grayscale_palette(int bit_depth, png_color *palette)
#if defined(PNG_READ_DITHER_SUPPORTED)
void
png_correct_palette(png_struct *png_ptr, png_color *palette,
png_correct_palette(png_structp png_ptr, png_colorp palette,
int num_palette)
{
if ((png_ptr->transformations & (PNG_GAMMA)) &&
@ -1344,15 +1352,16 @@ png_correct_palette(png_struct *png_ptr, png_color *palette,
background is the color (in rgb or grey or palette index, as
appropriate). note that paletted files are taken care of elsewhere */
void
png_do_background(png_row_info *row_info, png_bytef *row,
png_color_16 *trans_values, png_color_16 *background,
png_color_16 *background_1,
png_byte *gamma_table, png_byte *gamma_from_1, png_byte *gamma_to_1,
png_uint_16 **gamma_16, png_uint_16 **gamma_16_from_1,
png_uint_16 **gamma_16_to_1, int gamma_shift)
png_do_background(png_row_infop row_info, png_bytep row,
png_color_16p trans_values, png_color_16p background,
png_color_16p background_1,
png_bytep gamma_table, png_bytep gamma_from_1, png_bytep gamma_to_1,
png_uint_16pp gamma_16, png_uint_16pp gamma_16_from_1,
png_uint_16pp gamma_16_to_1, int gamma_shift)
{
png_bytef *sp, *dp;
png_bytep sp, dp;
png_uint_32 i;
int shift;
if (row && row_info && background &&
(!(row_info->color_type & PNG_COLOR_MASK_ALPHA) ||
@ -2016,15 +2025,16 @@ png_do_background(png_row_info *row_info, png_bytef *row,
you do this after you deal with the trasparency issue on grayscale
or rgb images. If your bit depth is 8, use gamma_table, if it is 16,
use gamma_16_table and gamma_shift. Build these with
build_gamma_table(). If your bit depth <= 8, gamma correct a
build_gamma_table(). If your bit depth < 8, gamma correct a
palette, not the data. */
void
png_do_gamma(png_row_info *row_info, png_bytef *row,
png_byte *gamma_table, png_uint_16 **gamma_16_table,
png_do_gamma(png_row_infop row_info, png_bytep row,
png_bytep gamma_table, png_uint_16pp gamma_16_table,
int gamma_shift)
{
png_bytef *sp;
png_bytep sp;
png_uint_32 i;
if (row && row_info && ((row_info->bit_depth <= 8 && gamma_table) ||
(row_info->bit_depth == 16 && gamma_16_table)))
{
@ -2177,13 +2187,14 @@ png_do_gamma(png_row_info *row_info, png_bytef *row,
/* expands a palette row to an rgb or rgba row depending
upon whether you supply trans and num_trans */
void
png_do_expand_palette(png_row_info *row_info, png_bytef *row,
png_color *palette,
png_byte *trans, int num_trans)
png_do_expand_palette(png_row_infop row_info, png_bytep row,
png_colorp palette,
png_bytep trans, int num_trans)
{
int shift, value;
png_bytef *sp, *dp;
png_bytep sp, dp;
png_uint_32 i;
if (row && row_info && row_info->color_type == PNG_COLOR_TYPE_PALETTE)
{
if (row_info->bit_depth < 8)
@ -2313,12 +2324,13 @@ png_do_expand_palette(png_row_info *row_info, png_bytef *row,
/* if the bit depth < 8, it is expanded to 8. Also, if the
transparency value is supplied, an alpha channel is built. */
void
png_do_expand(png_row_info *row_info, png_bytef *row,
png_color_16 *trans_value)
png_do_expand(png_row_infop row_info, png_bytep row,
png_color_16p trans_value)
{
int shift, value;
png_bytef *sp, *dp;
png_bytep sp, dp;
png_uint_32 i;
if (row && row_info)
{
if (row_info->color_type == PNG_COLOR_TYPE_GRAY &&
@ -2499,11 +2511,12 @@ png_do_expand(png_row_info *row_info, png_bytef *row,
#if defined(PNG_READ_DITHER_SUPPORTED)
void
png_do_dither(png_row_info *row_info, png_bytef *row,
png_byte *palette_lookup, png_byte *dither_lookup)
png_do_dither(png_row_infop row_info, png_bytep row,
png_bytep palette_lookup, png_bytep dither_lookup)
{
png_bytef *sp, *dp;
png_bytep sp, dp;
png_uint_32 i;
if (row && row_info)
{
if (row_info->color_type == PNG_COLOR_TYPE_RGB &&
@ -2590,7 +2603,7 @@ static int png_gamma_shift[] =
{0x10, 0x21, 0x42, 0x84, 0x110, 0x248, 0x550, 0xff0};
void
png_build_gamma_table(png_struct *png_ptr)
png_build_gamma_table(png_structp png_ptr)
{
if (png_ptr->bit_depth <= 8)
{
@ -2599,7 +2612,7 @@ png_build_gamma_table(png_struct *png_ptr)
g = 1.0 / (png_ptr->gamma * png_ptr->display_gamma);
png_ptr->gamma_table = (png_byte *)png_malloc(png_ptr,
png_ptr->gamma_table = (png_bytep)png_malloc(png_ptr,
(png_uint_32)256);
for (i = 0; i < 256; i++)
@ -2612,7 +2625,7 @@ png_build_gamma_table(png_struct *png_ptr)
{
g = 1.0 / (png_ptr->gamma);
png_ptr->gamma_to_1 = (png_byte *)png_malloc(png_ptr,
png_ptr->gamma_to_1 = (png_bytep)png_malloc(png_ptr,
(png_uint_32)256);
for (i = 0; i < 256; i++)
@ -2623,7 +2636,7 @@ png_build_gamma_table(png_struct *png_ptr)
g = 1.0 / (png_ptr->display_gamma);
png_ptr->gamma_from_1 = (png_byte *)png_malloc(png_ptr,
png_ptr->gamma_from_1 = (png_bytep)png_malloc(png_ptr,
(png_uint_32)256);
for (i = 0; i < 256; i++)
@ -2637,9 +2650,8 @@ png_build_gamma_table(png_struct *png_ptr)
{
double g;
int i, j, shift, num;
png_uint_32 ig;
#if defined(PNG_READ_sBIT_SUPPORTED)
int sig_bit;
png_uint_32 ig;
if (png_ptr->color_type & PNG_COLOR_MASK_COLOR)
{
@ -2657,7 +2669,6 @@ png_build_gamma_table(png_struct *png_ptr)
if (sig_bit > 0)
shift = 16 - sig_bit;
else
#endif /* PNG_READ_sBIT_SUPPORTED */
shift = 0;
if (png_ptr->transformations & PNG_16_TO_8)
@ -2677,8 +2688,8 @@ png_build_gamma_table(png_struct *png_ptr)
g = 1.0 / (png_ptr->gamma * png_ptr->display_gamma);
png_ptr->gamma_16_table = (png_uint_16 **)png_malloc(png_ptr,
num * sizeof (png_uint_16 *));
png_ptr->gamma_16_table = (png_uint_16pp)png_malloc(png_ptr,
num * sizeof (png_uint_16p ));
if ((png_ptr->transformations & PNG_16_TO_8) &&
!(png_ptr->transformations & PNG_BACKGROUND))
@ -2688,7 +2699,7 @@ png_build_gamma_table(png_struct *png_ptr)
for (i = 0; i < num; i++)
{
png_ptr->gamma_16_table[i] = (png_uint_16 *)png_malloc(png_ptr,
png_ptr->gamma_16_table[i] = (png_uint_16p)png_malloc(png_ptr,
256 * sizeof (png_uint_16));
}
@ -2701,14 +2712,16 @@ png_build_gamma_table(png_struct *png_ptr)
max = (png_uint_32)(fin * (double)(num << 8));
while (last <= max)
{
png_ptr->gamma_16_table[(int)(last >> 8)][(int)(last & 0xff)] =
png_ptr->gamma_16_table[(int)(last & 0xff) >> shift]
[(int)(last >> (8 - shift))] =
(png_uint_16)i | ((png_uint_16)i << 8);
last++;
}
}
while (last < (num << 8))
while (last < ((png_uint_32)num << 8))
{
png_ptr->gamma_16_table[(int)(last >> 8)][(int)(last & 0xff)] =
png_ptr->gamma_16_table[(int)(last & 0xff) >> shift]
[(int)(last >> (8 - shift))] =
(png_uint_16)65535L;
last++;
}
@ -2717,7 +2730,7 @@ png_build_gamma_table(png_struct *png_ptr)
{
for (i = 0; i < num; i++)
{
png_ptr->gamma_16_table[i] = (png_uint_16 *)png_malloc(png_ptr,
png_ptr->gamma_16_table[i] = (png_uint_16p)png_malloc(png_ptr,
256 * sizeof (png_uint_16));
ig = (((png_uint_32)i *
@ -2735,12 +2748,12 @@ png_build_gamma_table(png_struct *png_ptr)
{
g = 1.0 / (png_ptr->gamma);
png_ptr->gamma_16_to_1 = (png_uint_16 **)png_malloc(png_ptr,
num * sizeof (png_uint_16 *));
png_ptr->gamma_16_to_1 = (png_uint_16pp)png_malloc(png_ptr,
num * sizeof (png_uint_16p ));
for (i = 0; i < num; i++)
{
png_ptr->gamma_16_to_1[i] = (png_uint_16 *)png_malloc(png_ptr,
png_ptr->gamma_16_to_1[i] = (png_uint_16p)png_malloc(png_ptr,
256 * sizeof (png_uint_16));
ig = (((png_uint_32)i *
@ -2754,12 +2767,12 @@ png_build_gamma_table(png_struct *png_ptr)
}
g = 1.0 / (png_ptr->display_gamma);
png_ptr->gamma_16_from_1 = (png_uint_16 **)png_malloc(png_ptr,
num * sizeof (png_uint_16 *));
png_ptr->gamma_16_from_1 = (png_uint_16pp)png_malloc(png_ptr,
num * sizeof (png_uint_16p));
for (i = 0; i < num; i++)
{
png_ptr->gamma_16_from_1[i] = (png_uint_16 *)png_malloc(png_ptr,
png_ptr->gamma_16_from_1[i] = (png_uint_16p)png_malloc(png_ptr,
256 * sizeof (png_uint_16));
ig = (((png_uint_32)i *

223
pngrutil.c
View File

@ -1,10 +1,10 @@
/* pngrutil.c - utilities to read a png file
libpng 1.0 beta 2 - version 0.81
libpng 1.0 beta 2 - version 0.85
For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
August 24, 1995
December 19, 1995
*/
#define PNG_INTERNAL
@ -12,7 +12,7 @@
/* grab an uint 32 from a buffer */
png_uint_32
png_get_uint_32(png_byte *buf)
png_get_uint_32(png_bytep buf)
{
png_uint_32 i;
@ -26,7 +26,7 @@ png_get_uint_32(png_byte *buf)
/* grab an uint 16 from a buffer */
png_uint_16
png_get_uint_16(png_byte *buf)
png_get_uint_16(png_bytep buf)
{
png_uint_16 i;
@ -38,33 +38,33 @@ png_get_uint_16(png_byte *buf)
/* read data, and run it through the crc */
void
png_crc_read(png_struct *png_ptr, png_bytef *buf, png_uint_32 length)
png_crc_read(png_structp png_ptr, png_bytep buf, png_uint_32 length)
{
(*(png_ptr->read_data_fn))(png_ptr, buf, length);
png_read_data(png_ptr, buf, length);
png_calculate_crc(png_ptr, buf, length);
}
/* skip data, but calcuate the crc anyway */
void
png_crc_skip(png_struct *png_ptr, png_uint_32 length)
png_crc_skip(png_structp png_ptr, png_uint_32 length)
{
png_uint_32 i;
for (i = length; i > png_ptr->zbuf_size; i -= png_ptr->zbuf_size)
{
(*(png_ptr->read_data_fn))(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size);
png_read_data(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size);
png_calculate_crc(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size);
}
if (i)
{
(*(png_ptr->read_data_fn))(png_ptr, png_ptr->zbuf, i);
png_read_data(png_ptr, png_ptr->zbuf, i);
png_calculate_crc(png_ptr, png_ptr->zbuf, i);
}
}
/* read and check the IDHR chunk */
void
png_handle_IHDR(png_struct *png_ptr, png_info *info, png_uint_32 length)
png_handle_IHDR(png_structp png_ptr, png_infop info, png_uint_32 length)
{
png_byte buf[13];
png_uint_32 width, height;
@ -73,7 +73,7 @@ png_handle_IHDR(png_struct *png_ptr, png_info *info, png_uint_32 length)
/* check the length */
if (length != 13)
(*(png_ptr->error_fn))(png_ptr, "Invalid IHDR chunk");
png_error(png_ptr, "Invalid IHDR chunk");
png_crc_read(png_ptr, buf, 13);
@ -87,36 +87,36 @@ png_handle_IHDR(png_struct *png_ptr, png_info *info, png_uint_32 length)
/* check for width and height valid values */
if (width == 0 || height == 0)
(*(png_ptr->error_fn))(png_ptr, "Invalid Width or Height Found");
png_error(png_ptr, "Invalid Width or Height Found");
/* check other values */
if (bit_depth != 1 && bit_depth != 2 &&
bit_depth != 4 && bit_depth != 8 &&
bit_depth != 16)
(*(png_ptr->error_fn))(png_ptr, "Invalid Bit Depth Found");
png_error(png_ptr, "Invalid Bit Depth Found");
if (color_type < 0 || color_type == 1 ||
color_type == 5 || color_type > 6)
(*(png_ptr->error_fn))(png_ptr, "Invalid Color Type Found");
png_error(png_ptr, "Invalid Color Type Found");
if (color_type == PNG_COLOR_TYPE_PALETTE &&
bit_depth == 16)
(*(png_ptr->error_fn))(png_ptr, "Found Invalid Color Type and Bit Depth Combination");
png_error(png_ptr, "Found Invalid Color Type and Bit Depth Combination");
if ((color_type == PNG_COLOR_TYPE_RGB ||
color_type == PNG_COLOR_TYPE_GRAY_ALPHA ||
color_type == PNG_COLOR_TYPE_RGB_ALPHA) &&
bit_depth < 8)
(*(png_ptr->error_fn))(png_ptr, "Found Invalid Color Type and Bit Depth Combination");
png_error(png_ptr, "Found Invalid Color Type and Bit Depth Combination");
if (interlace_type > 1)
(*(png_ptr->error_fn))(png_ptr, "Found Unsupported Interlace Value");
png_error(png_ptr, "Found Invalid Interlace Value");
if (compression_type > 0)
(*(png_ptr->error_fn))(png_ptr, "Found Unsupported Compression Value");
png_error(png_ptr, "Found Invalid Compression Value");
if (filter_type > 0)
(*(png_ptr->error_fn))(png_ptr, "Found Unsupported Filter Value");
png_error(png_ptr, "Found Invalid Filter Value");
/* set internal variables */
png_ptr->width = width;
@ -154,18 +154,16 @@ png_handle_IHDR(png_struct *png_ptr, png_info *info, png_uint_32 length)
/* read and check the palette */
void
png_handle_PLTE(png_struct *png_ptr, png_info *info, png_uint_32 length)
png_handle_PLTE(png_structp png_ptr, png_infop info, png_uint_32 length)
{
int num, i;
png_color *palette;
png_colorp palette;
if (length % 3)
(*(png_ptr->error_fn))(png_ptr, "Invalid Palette Chunk");
png_error(png_ptr, "Invalid Palette Chunk");
num = (int)length / 3;
palette = (png_color *)png_malloc(png_ptr, num * sizeof (png_color));
png_ptr->do_free |= PNG_FREE_PALETTE;
palette = (png_colorp)png_malloc(png_ptr, num * sizeof (png_color));
for (i = 0; i < num; i++)
{
png_byte buf[3];
@ -183,7 +181,7 @@ png_handle_PLTE(png_struct *png_ptr, png_info *info, png_uint_32 length)
#if defined(PNG_READ_gAMA_SUPPORTED)
void
png_handle_gAMA(png_struct *png_ptr, png_info *info, png_uint_32 length)
png_handle_gAMA(png_structp png_ptr, png_infop info, png_uint_32 length)
{
png_uint_32 igamma;
float gamma;
@ -191,7 +189,6 @@ png_handle_gAMA(png_struct *png_ptr, png_info *info, png_uint_32 length)
if (length != 4)
{
(*(png_ptr->warning_fn))(png_ptr,"Incorrect gAMA chunk length");
png_crc_skip(png_ptr, length);
return;
}
@ -210,10 +207,9 @@ png_handle_gAMA(png_struct *png_ptr, png_info *info, png_uint_32 length)
#if defined(PNG_READ_sBIT_SUPPORTED)
void
png_handle_sBIT(png_struct *png_ptr, png_info *info, png_uint_32 length)
png_handle_sBIT(png_structp png_ptr, png_infop info, png_uint_32 length)
{
int slen;
register int index = 0;
png_byte buf[4];
if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
@ -223,7 +219,6 @@ png_handle_sBIT(png_struct *png_ptr, png_info *info, png_uint_32 length)
if (length != (png_uint_32)slen)
{
(*(png_ptr->warning_fn))(png_ptr, "Incorrect sBIT chunk length");
png_crc_skip(png_ptr, length);
return;
}
@ -231,35 +226,23 @@ png_handle_sBIT(png_struct *png_ptr, png_info *info, png_uint_32 length)
png_crc_read(png_ptr, buf, length);
if (png_ptr->color_type & PNG_COLOR_MASK_COLOR)
{
png_ptr->sig_bit.red = buf[index++];
png_ptr->sig_bit.green = buf[index++];
png_ptr->sig_bit.blue = buf[index++];
png_ptr->sig_bit.gray = 0;
png_ptr->sig_bit.red = buf[0];
png_ptr->sig_bit.green = buf[1];
png_ptr->sig_bit.blue = buf[2];
png_ptr->sig_bit.alpha = buf[3];
}
else
{
png_ptr->sig_bit.red = 0;
png_ptr->sig_bit.green = 0;
png_ptr->sig_bit.blue = 0;
png_ptr->sig_bit.gray = buf[0];
png_ptr->sig_bit.alpha = buf[1];
}
if (png_ptr->color_type & PNG_COLOR_MASK_ALPHA)
{
png_ptr->sig_bit.alpha = buf[index++];
}
else
{
png_ptr->sig_bit.alpha = 0;
}
png_read_sBIT(png_ptr, info, &(png_ptr->sig_bit));
}
#endif
#if defined(PNG_READ_cHRM_SUPPORTED)
void
png_handle_cHRM(png_struct *png_ptr, png_info *info, png_uint_32 length)
png_handle_cHRM(png_structp png_ptr, png_infop info, png_uint_32 length)
{
png_byte buf[4];
png_uint_32 v;
@ -267,7 +250,6 @@ png_handle_cHRM(png_struct *png_ptr, png_info *info, png_uint_32 length)
if (length != 32)
{
(*(png_ptr->warning_fn))(png_ptr, "Incorrect cHRM chunk length");
png_crc_skip(png_ptr, length);
return;
}
@ -311,19 +293,17 @@ png_handle_cHRM(png_struct *png_ptr, png_info *info, png_uint_32 length)
#if defined(PNG_READ_tRNS_SUPPORTED)
void
png_handle_tRNS(png_struct *png_ptr, png_info *info, png_uint_32 length)
png_handle_tRNS(png_structp png_ptr, png_infop info, png_uint_32 length)
{
if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
{
if (length > png_ptr->num_palette)
{
(*(png_ptr->warning_fn))(png_ptr, "Incorrect tRNS chunk length");
png_crc_skip(png_ptr, length);
return;
}
png_ptr->trans = png_malloc(png_ptr, length);
png_ptr->do_free |= PNG_FREE_TRANS;
png_ptr->trans = (png_bytep)png_malloc(png_ptr, length);
png_crc_read(png_ptr, png_ptr->trans, length);
png_ptr->num_trans = (int)length;
}
@ -333,7 +313,6 @@ png_handle_tRNS(png_struct *png_ptr, png_info *info, png_uint_32 length)
if (length != 6)
{
(*(png_ptr->warning_fn))(png_ptr, "Incorrect tRNS chunk length");
png_crc_skip(png_ptr, length);
return;
}
@ -350,7 +329,6 @@ png_handle_tRNS(png_struct *png_ptr, png_info *info, png_uint_32 length)
if (length != 2)
{
(*(png_ptr->warning_fn))(png_ptr, "Incorrect tRNS chunk length");
png_crc_skip(png_ptr, length);
return;
}
@ -360,7 +338,7 @@ png_handle_tRNS(png_struct *png_ptr, png_info *info, png_uint_32 length)
png_ptr->trans_values.gray = png_get_uint_16(buf);
}
else
(*(png_ptr->error_fn))(png_ptr, "Invalid tRNS chunk");
png_error(png_ptr, "Invalid tRNS chunk");
png_read_tRNS(png_ptr, info, png_ptr->trans, png_ptr->num_trans,
&(png_ptr->trans_values));
@ -369,7 +347,7 @@ png_handle_tRNS(png_struct *png_ptr, png_info *info, png_uint_32 length)
#if defined(PNG_READ_bKGD_SUPPORTED)
void
png_handle_bKGD(png_struct *png_ptr, png_info *info, png_uint_32 length)
png_handle_bKGD(png_structp png_ptr, png_infop info, png_uint_32 length)
{
int truelen;
png_byte buf[6];
@ -383,7 +361,6 @@ png_handle_bKGD(png_struct *png_ptr, png_info *info, png_uint_32 length)
if (length != (png_uint_32)truelen)
{
(*(png_ptr->warning_fn))(png_ptr, "Incorrect bKGD chunk length");
png_crc_skip(png_ptr, length);
return;
}
@ -406,21 +383,19 @@ png_handle_bKGD(png_struct *png_ptr, png_info *info, png_uint_32 length)
#if defined(PNG_READ_hIST_SUPPORTED)
void
png_handle_hIST(png_struct *png_ptr, png_info *info, png_uint_32 length)
png_handle_hIST(png_structp png_ptr, png_infop info, png_uint_32 length)
{
int num, i;
if (length != 2 * png_ptr->num_palette)
{
(*(png_ptr->warning_fn))(png_ptr, "Incorrect hIST chunk length");
png_crc_skip(png_ptr, length);
return;
}
num = (int)length / 2;
png_ptr->hist = png_malloc(png_ptr, num * sizeof (png_uint_16));
png_ptr->do_free |= PNG_FREE_HIST;
png_ptr->hist = (png_uint_16p)png_malloc(png_ptr,
num * sizeof (png_uint_16));
for (i = 0; i < num; i++)
{
png_byte buf[2];
@ -434,7 +409,7 @@ png_handle_hIST(png_struct *png_ptr, png_info *info, png_uint_32 length)
#if defined(PNG_READ_pHYs_SUPPORTED)
void
png_handle_pHYs(png_struct *png_ptr, png_info *info, png_uint_32 length)
png_handle_pHYs(png_structp png_ptr, png_infop info, png_uint_32 length)
{
png_byte buf[9];
png_uint_32 res_x, res_y;
@ -442,7 +417,6 @@ png_handle_pHYs(png_struct *png_ptr, png_info *info, png_uint_32 length)
if (length != 9)
{
(*(png_ptr->warning_fn))(png_ptr, "Incorrect pHYS chunk length");
png_crc_skip(png_ptr, length);
return;
}
@ -458,7 +432,7 @@ png_handle_pHYs(png_struct *png_ptr, png_info *info, png_uint_32 length)
#if defined(PNG_READ_oFFs_SUPPORTED)
void
png_handle_oFFs(png_struct *png_ptr, png_info *info, png_uint_32 length)
png_handle_oFFs(png_structp png_ptr, png_infop info, png_uint_32 length)
{
png_byte buf[9];
png_uint_32 offset_x, offset_y;
@ -466,7 +440,6 @@ png_handle_oFFs(png_struct *png_ptr, png_info *info, png_uint_32 length)
if (length != 9)
{
(*(png_ptr->warning_fn))(png_ptr, "Incorrect oFFs chunk length");
png_crc_skip(png_ptr, length);
return;
}
@ -482,14 +455,13 @@ png_handle_oFFs(png_struct *png_ptr, png_info *info, png_uint_32 length)
#if defined(PNG_READ_tIME_SUPPORTED)
void
png_handle_tIME(png_struct *png_ptr, png_info *info, png_uint_32 length)
png_handle_tIME(png_structp png_ptr, png_infop info, png_uint_32 length)
{
png_byte buf[7];
png_time mod_time;
if (length != 7)
{
(*(png_ptr->warning_fn))(png_ptr, "Incorrect tIME chunk length");
png_crc_skip(png_ptr, length);
return;
}
@ -510,15 +482,15 @@ png_handle_tIME(png_struct *png_ptr, png_info *info, png_uint_32 length)
#if defined(PNG_READ_tEXt_SUPPORTED)
/* note: this does not correctly handle chunks that are > 64K */
void
png_handle_tEXt(png_struct *png_ptr, png_info *info, png_uint_32 length)
png_handle_tEXt(png_structp png_ptr, png_infop info, png_uint_32 length)
{
charf *key;
charf *text;
png_charp key;
png_charp text;
text = NULL;
key = (charf *)png_large_malloc(png_ptr, length + 1);
png_crc_read(png_ptr, (png_bytef *)key, length);
key = (png_charp )png_large_malloc(png_ptr, length + 1);
png_crc_read(png_ptr, (png_bytep )key, length);
key[(png_size_t)length] = '\0';
for (text = key; *text; text++)
@ -534,17 +506,17 @@ png_handle_tEXt(png_struct *png_ptr, png_info *info, png_uint_32 length)
#if defined(PNG_READ_zTXt_SUPPORTED)
/* note: this does not correctly handle chunks that are > 64K compressed */
void
png_handle_zTXt(png_struct *png_ptr, png_info *info, png_uint_32 length)
png_handle_zTXt(png_structp png_ptr, png_infop info, png_uint_32 length)
{
charf *key;
charf *text;
int ret = Z_STREAM_END;
png_charp key;
png_charp text;
int ret;
png_uint_32 text_size, key_size;
text = NULL;
key = png_large_malloc(png_ptr, length + 1);
png_crc_read(png_ptr, (png_bytef *)key, length);
png_crc_read(png_ptr, (png_bytep )key, length);
key[(png_size_t)length] = '\0';
for (text = key; *text; text++)
@ -553,7 +525,6 @@ png_handle_zTXt(png_struct *png_ptr, png_info *info, png_uint_32 length)
/* zTXt can't have zero text */
if (text == key + (png_size_t)length)
{
(*(png_ptr->warning_fn))(png_ptr, "Zero length zTXt chunk");
png_large_free(png_ptr, key);
return;
}
@ -568,7 +539,7 @@ png_handle_zTXt(png_struct *png_ptr, png_info *info, png_uint_32 length)
text++;
png_ptr->zstream->next_in = (png_bytef *)text;
png_ptr->zstream->next_in = (png_bytep )text;
png_ptr->zstream->avail_in = (uInt)(length - (text - key));
png_ptr->zstream->next_out = png_ptr->zbuf;
png_ptr->zstream->avail_out = (png_size_t)png_ptr->zbuf_size;
@ -582,10 +553,6 @@ png_handle_zTXt(png_struct *png_ptr, png_info *info, png_uint_32 length)
ret = inflate(png_ptr->zstream, Z_PARTIAL_FLUSH);
if (ret != Z_OK && ret != Z_STREAM_END)
{
if (png_ptr->zstream->msg)
(*(png_ptr->warning_fn))(png_ptr,png_ptr->zstream->msg);
else
(*(png_ptr->warning_fn))(png_ptr,"zTXt decompression error");
inflateReset(png_ptr->zstream);
png_ptr->zstream->avail_in = 0;
png_large_free(png_ptr, key);
@ -596,7 +563,7 @@ png_handle_zTXt(png_struct *png_ptr, png_info *info, png_uint_32 length)
{
if (!text)
{
text = png_malloc(png_ptr,
text = (png_charp)png_malloc(png_ptr,
png_ptr->zbuf_size - png_ptr->zstream->avail_out +
key_size + 1);
png_memcpy(text + (png_size_t)key_size, png_ptr->zbuf,
@ -608,7 +575,7 @@ png_handle_zTXt(png_struct *png_ptr, png_info *info, png_uint_32 length)
}
else
{
charf *tmp;
png_charp tmp;
tmp = text;
text = png_large_malloc(png_ptr, text_size +
@ -666,7 +633,7 @@ 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.
*/
void
png_combine_row(png_struct *png_ptr, png_bytef *row,
png_combine_row(png_structp png_ptr, png_bytep row,
int mask)
{
if (mask == 0xff)
@ -681,8 +648,8 @@ png_combine_row(png_struct *png_ptr, png_bytef *row,
{
case 1:
{
png_bytef *sp;
png_bytef *dp;
png_bytep sp;
png_bytep dp;
int m;
int shift;
png_uint_32 i;
@ -719,8 +686,8 @@ png_combine_row(png_struct *png_ptr, png_bytef *row,
}
case 2:
{
png_bytef *sp;
png_bytef *dp;
png_bytep sp;
png_bytep dp;
int m;
int shift;
png_uint_32 i;
@ -756,8 +723,8 @@ png_combine_row(png_struct *png_ptr, png_bytef *row,
}
case 4:
{
png_bytef *sp;
png_bytef *dp;
png_bytep sp;
png_bytep dp;
int m;
int shift;
png_uint_32 i;
@ -793,8 +760,8 @@ png_combine_row(png_struct *png_ptr, png_bytef *row,
}
default:
{
png_bytef *sp;
png_bytef *dp;
png_bytep sp;
png_bytep dp;
png_uint_32 i;
int pixel_bytes, m;
@ -826,7 +793,7 @@ png_combine_row(png_struct *png_ptr, png_bytef *row,
#if defined(PNG_READ_INTERLACING_SUPPORTED)
void
png_do_read_interlace(png_row_info *row_info, png_bytef *row, int pass)
png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass)
{
if (row && row_info)
{
@ -838,7 +805,7 @@ png_do_read_interlace(png_row_info *row_info, png_bytef *row, int pass)
{
case 1:
{
png_bytef *sp, *dp;
png_bytep sp, dp;
int sshift, dshift;
png_byte v;
png_uint_32 i;
@ -875,7 +842,7 @@ png_do_read_interlace(png_row_info *row_info, png_bytef *row, int pass)
}
case 2:
{
png_bytef *sp, *dp;
png_bytep sp, dp;
int sshift, dshift;
png_byte v;
png_uint_32 i, j;
@ -911,7 +878,7 @@ png_do_read_interlace(png_row_info *row_info, png_bytef *row, int pass)
}
case 4:
{
png_bytef *sp, *dp;
png_bytep sp, dp;
int sshift, dshift;
png_byte v;
png_uint_32 i;
@ -948,7 +915,7 @@ png_do_read_interlace(png_row_info *row_info, png_bytef *row, int pass)
}
default:
{
png_bytef *sp, *dp;
png_bytep sp, dp;
png_byte v[8];
png_uint_32 i;
int j;
@ -979,8 +946,8 @@ png_do_read_interlace(png_row_info *row_info, png_bytef *row, int pass)
#endif
void
png_read_filter_row(png_row_info *row_info, png_bytef *row,
png_bytef *prev_row, int filter)
png_read_filter_row(png_row_infop row_info, png_bytep row,
png_bytep prev_row, int filter)
{
switch (filter)
{
@ -990,8 +957,8 @@ png_read_filter_row(png_row_info *row_info, png_bytef *row,
{
png_uint_32 i;
int bpp;
png_bytef *rp;
png_bytef *lp;
png_bytep rp;
png_bytep lp;
bpp = (row_info->pixel_depth + 7) / 8;
for (i = (png_uint_32)bpp, rp = row + bpp, lp = row;
@ -1004,8 +971,8 @@ png_read_filter_row(png_row_info *row_info, png_bytef *row,
case 2:
{
png_uint_32 i;
png_bytef *rp;
png_bytef *pp;
png_bytep rp;
png_bytep pp;
for (i = 0, rp = row, pp = prev_row;
i < row_info->rowbytes; i++, rp++, pp++)
@ -1018,9 +985,9 @@ png_read_filter_row(png_row_info *row_info, png_bytef *row,
{
png_uint_32 i;
int bpp;
png_bytef *rp;
png_bytef *pp;
png_bytef *lp;
png_bytep rp;
png_bytep pp;
png_bytep lp;
bpp = (row_info->pixel_depth + 7) / 8;
for (i = 0, rp = row, pp = prev_row;
@ -1040,10 +1007,10 @@ png_read_filter_row(png_row_info *row_info, png_bytef *row,
{
int bpp;
png_uint_32 i;
png_bytef *rp;
png_bytef *pp;
png_bytef *lp;
png_bytef *cp;
png_bytep rp;
png_bytep pp;
png_bytep lp;
png_bytep cp;
bpp = (row_info->pixel_depth + 7) / 8;
for (i = 0, rp = row, pp = prev_row,
@ -1084,7 +1051,7 @@ png_read_filter_row(png_row_info *row_info, png_bytef *row,
}
void
png_read_finish_row(png_struct *png_ptr)
png_read_finish_row(png_structp png_ptr)
{
png_ptr->row_number++;
if (png_ptr->row_number < png_ptr->num_rows)
@ -1138,19 +1105,19 @@ png_read_finish_row(png_struct *png_ptr)
png_byte buf[4];
png_uint_32 crc;
(*(png_ptr->read_data_fn))(png_ptr, buf, 4);
png_read_data(png_ptr, buf, 4);
crc = png_get_uint_32(buf);
if (((crc ^ 0xffffffffL) & 0xffffffffL) !=
(png_ptr->crc & 0xffffffffL))
(*(png_ptr->error_fn))(png_ptr, "Bad CRC value");
png_error(png_ptr, "Bad CRC value");
(*(png_ptr->read_data_fn))(png_ptr, buf, 4);
png_read_data(png_ptr, buf, 4);
png_ptr->idat_size = png_get_uint_32(buf);
png_reset_crc(png_ptr);
png_crc_read(png_ptr, buf, 4);
if (memcmp(buf, png_IDAT, 4))
(*(png_ptr->error_fn))(png_ptr, "Not enough image data");
if (png_memcmp(buf, png_IDAT, 4))
png_error(png_ptr, "Not enough image data");
}
png_ptr->zstream->avail_in = (uInt)png_ptr->zbuf_size;
@ -1165,22 +1132,22 @@ png_read_finish_row(png_struct *png_ptr)
{
if (!(png_ptr->zstream->avail_out) || png_ptr->zstream->avail_in ||
png_ptr->idat_size)
(*(png_ptr->warning_fn))(png_ptr, "Extra compressed data");
png_error(png_ptr, "Extra compressed data");
png_ptr->mode = PNG_AT_LAST_IDAT;
break;
}
if (ret != Z_OK)
(*(png_ptr->error_fn))(png_ptr, "Compression Error");
png_error(png_ptr, "Compression Error");
if (!(png_ptr->zstream->avail_out))
(*(png_ptr->error_fn))(png_ptr, "Extra compressed data");
png_error(png_ptr, "Extra compressed data");
} while (1);
png_ptr->zstream->avail_out = 0;
}
if (png_ptr->idat_size || png_ptr->zstream->avail_in)
(*(png_ptr->warning_fn))(png_ptr, "Extra compression data");
png_error(png_ptr, "Extra compression data");
inflateReset(png_ptr->zstream);
@ -1188,7 +1155,7 @@ png_read_finish_row(png_struct *png_ptr)
}
void
png_read_start_row(png_struct *png_ptr)
png_read_start_row(png_structp png_ptr)
{
int max_pixel_depth;
png_uint_32 rowbytes;
@ -1292,13 +1259,13 @@ png_read_start_row(png_struct *png_ptr)
1 + ((max_pixel_depth + 7) >> 3);
#ifdef PNG_MAX_MALLOC_64K
if (rowbytes > 65536L)
(*(png_ptr->error_fn))(png_ptr, "This image requires a row greater then 64KB");
png_error(png_ptr, "This image requires a row greater then 64KB");
#endif
png_ptr->row_buf = (png_bytef *)png_large_malloc(png_ptr, rowbytes);
png_ptr->row_buf = (png_bytep )png_large_malloc(png_ptr, rowbytes);
#ifdef PNG_MAX_MALLOC_64K
if (png_ptr->rowbytes + 1 > 65536L)
(*(png_ptr->error_fn))(png_ptr, "This image requires a row greater then 64KB");
png_error(png_ptr, "This image requires a row greater then 64KB");
#endif
png_ptr->prev_row = png_large_malloc(png_ptr,
png_ptr->rowbytes + 1);

26
pngtest.c
View File

@ -15,11 +15,12 @@
#endif
/* defined so I can write to a file on gui/windowing platforms */
#define STDERR stderr
/* #define STDERR stderr */
#define STDERR stdout /* for DOS */
/* input and output filenames */
char inname[] = "pngtest.png";
char outname[] = "testout.png";
char outname[] = "pngout.png";
png_struct read_ptr;
png_struct write_ptr;
@ -31,12 +32,12 @@ char inbuf[256], outbuf[256];
int main()
{
FILE *fpin, *fpout;
png_byte *row_buf;
png_bytep row_buf;
png_uint_32 rowbytes;
png_uint_32 y;
int channels, num_pass, pass;
row_buf = (png_byte *)0;
row_buf = (png_bytep )0;
fprintf(STDERR, "Testing libpng version %s\n", PNG_LIBPNG_VER_STRING);
@ -79,10 +80,10 @@ int main()
return 1;
}
png_info_init(&info_ptr);
png_info_init(&end_info);
png_read_init(&read_ptr);
png_write_init(&write_ptr);
png_info_init(&info_ptr);
png_info_init(&end_info);
png_init_io(&read_ptr, fpin);
png_init_io(&write_ptr, fpout);
@ -97,15 +98,12 @@ int main()
if (info_ptr.color_type & 4)
channels++;
png_set_flush(&write_ptr, 20);
png_set_compression_level(&write_ptr, 9);
rowbytes = ((info_ptr.width * info_ptr.bit_depth * channels + 7) >> 3);
row_buf = (png_byte *)malloc((size_t)rowbytes);
row_buf = (png_bytep )malloc((size_t)rowbytes);
if (!row_buf)
{
fprintf(STDERR, "no memory to allocate row buffer\n");
png_read_destroy(&read_ptr, &info_ptr, (png_info *)0);
png_read_destroy(&read_ptr, &info_ptr, (png_infop )0);
png_write_destroy(&write_ptr);
fclose(fpin);
fclose(fpout);
@ -126,8 +124,8 @@ int main()
{
for (y = 0; y < info_ptr.height; y++)
{
png_read_rows(&read_ptr, (png_bytef **)&row_buf, (png_bytef **)0, 1);
png_write_rows(&write_ptr, (png_bytef **)&row_buf, 1);
png_read_rows(&read_ptr, (png_bytepp )&row_buf, (png_bytepp )0, 1);
png_write_rows(&write_ptr, (png_bytepp )&row_buf, 1);
}
}
@ -140,7 +138,7 @@ int main()
fclose(fpin);
fclose(fpout);
free(row_buf);
free((void *)row_buf);
fpin = fopen(inname, "rb");

11
pngtodo.txt
View File

@ -1,18 +1,15 @@
pngtodo.txt - list of things to do for libpng
for 0.9
medium memory model
improved dithering?
improved dithering
final bug fixes
cHRM transformation
for 1.1
push reader
for 1.1 or later
after 1.0
overlaying one image on top of another
optional palette creation
histogram creation
text conversion between different code types
cHRM transformation
support for other chunks being defined (sCAl, the gIF series,
and others that people come up with).
pull writer

40
pngtrans.c
View File

@ -2,10 +2,10 @@
/* pngtrans.c - transforms the data in a row
routines used by both readers and writers
libpng 1.0 beta 2 - version 0.81
libpng 1.0 beta 2 - version 0.85
For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
August 24, 1995
December 19, 1995
*/
#define PNG_INTERNAL
@ -14,7 +14,7 @@
#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
/* turn on bgr to rgb mapping */
void
png_set_bgr(png_struct *png_ptr)
png_set_bgr(png_structp png_ptr)
{
png_ptr->transformations |= PNG_BGR;
}
@ -23,7 +23,7 @@ png_set_bgr(png_struct *png_ptr)
#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
/* turn on 16 bit byte swapping */
void
png_set_swap(png_struct *png_ptr)
png_set_swap(png_structp png_ptr)
{
if (png_ptr->bit_depth == 16)
png_ptr->transformations |= PNG_SWAP_BYTES;
@ -33,7 +33,7 @@ png_set_swap(png_struct *png_ptr)
#if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
/* turn on pixel packing */
void
png_set_packing(png_struct *png_ptr)
png_set_packing(png_structp png_ptr)
{
if (png_ptr->bit_depth < 8)
{
@ -45,7 +45,7 @@ png_set_packing(png_struct *png_ptr)
#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
void
png_set_shift(png_struct *png_ptr, png_color_8 *true_bits)
png_set_shift(png_structp png_ptr, png_color_8p true_bits)
{
png_ptr->transformations |= PNG_SHIFT;
png_ptr->shift = *true_bits;
@ -54,7 +54,7 @@ png_set_shift(png_struct *png_ptr, png_color_8 *true_bits)
#if defined(PNG_READ_INTERLACING_SUPPORTED) || defined(PNG_WRITE_INTERLACING_SUPPORTED)
int
png_set_interlace_handling(png_struct *png_ptr)
png_set_interlace_handling(png_structp png_ptr)
{
if (png_ptr->interlaced)
{
@ -68,7 +68,7 @@ png_set_interlace_handling(png_struct *png_ptr)
#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
void
png_set_filler(png_struct *png_ptr, int filler, int filler_loc)
png_set_filler(png_structp png_ptr, int filler, int filler_loc)
{
png_ptr->transformations |= PNG_FILLER;
png_ptr->filler = (png_byte)filler;
@ -80,13 +80,13 @@ png_set_filler(png_struct *png_ptr, int filler, int filler_loc)
/* old functions kept around for compatability purposes */
void
png_set_rgbx(png_struct *png_ptr)
png_set_rgbx(png_structp png_ptr)
{
png_set_filler(png_ptr, 0xff, PNG_FILLER_AFTER);
}
void
png_set_xrgb(png_struct *png_ptr)
png_set_xrgb(png_structp png_ptr)
{
png_set_filler(png_ptr, 0xff, PNG_FILLER_BEFORE);
}
@ -94,19 +94,19 @@ png_set_xrgb(png_struct *png_ptr)
#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
void
png_set_invert_mono(png_struct *png_ptr)
png_set_invert_mono(png_structp png_ptr)
{
png_ptr->transformations |= PNG_INVERT_MONO;
}
/* invert monocrome grayscale data */
void
png_do_invert(png_row_info *row_info, png_bytef *row)
png_do_invert(png_row_infop row_info, png_bytep row)
{
if (row && row_info && row_info->bit_depth == 1 &&
row_info->color_type == PNG_COLOR_TYPE_GRAY)
{
png_bytef *rp;
png_bytep rp;
png_uint_32 i;
for (i = 0, rp = row;
@ -122,11 +122,11 @@ png_do_invert(png_row_info *row_info, png_bytef *row)
#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
/* swaps byte order on 16 bit depth images */
void
png_do_swap(png_row_info *row_info, png_bytef *row)
png_do_swap(png_row_infop row_info, png_bytep row)
{
if (row && row_info && row_info->bit_depth == 16)
{
png_bytef *rp;
png_bytep rp;
png_byte t;
png_uint_32 i;
@ -145,13 +145,13 @@ png_do_swap(png_row_info *row_info, png_bytef *row)
#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
/* swaps red and blue */
void
png_do_bgr(png_row_info *row_info, png_bytef *row)
png_do_bgr(png_row_infop row_info, png_bytep row)
{
if (row && row_info && (row_info->color_type & 2))
{
if (row_info->color_type == 2 && row_info->bit_depth == 8)
{
png_bytef *rp;
png_bytep rp;
png_byte t;
png_uint_32 i;
@ -166,7 +166,7 @@ png_do_bgr(png_row_info *row_info, png_bytef *row)
}
else if (row_info->color_type == 6 && row_info->bit_depth == 8)
{
png_bytef *rp;
png_bytep rp;
png_byte t;
png_uint_32 i;
@ -181,7 +181,7 @@ png_do_bgr(png_row_info *row_info, png_bytef *row)
}
else if (row_info->color_type == 2 && row_info->bit_depth == 16)
{
png_bytef *rp;
png_bytep rp;
png_byte t[2];
png_uint_32 i;
@ -199,7 +199,7 @@ png_do_bgr(png_row_info *row_info, png_bytef *row)
}
else if (row_info->color_type == 6 && row_info->bit_depth == 16)
{
png_bytef *rp;
png_bytep rp;
png_byte t[2];
png_uint_32 i;

102
pngwrite.c
View File

@ -1,10 +1,10 @@
/* pngwrite.c - general routines to write a png file
libpng 1.0 beta 2 - version 0.81
libpng 1.0 beta 2 - version 0.85
For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
August 24, 1995
December 19, 1995
*/
/* get internal access to png.h */
@ -21,7 +21,7 @@
If you have long comments, I suggest writing them in png_write_end(),
and compressing them. */
void
png_write_info(png_struct *png_ptr, png_info *info)
png_write_info(png_structp png_ptr, png_infop info)
{
png_write_sig(png_ptr); /* write PNG signature */
/* write IHDR information. */
@ -57,30 +57,25 @@ png_write_info(png_struct *png_ptr, png_info *info)
if (info->valid & PNG_INFO_bKGD)
png_write_bKGD(png_ptr, &(info->background), info->color_type);
#endif
#if defined(PNG_WRITE_hIST_SUPPORTED)
if (info->valid & PNG_INFO_hIST)
png_write_hIST(png_ptr, info->hist, info->num_palette);
#endif
#if defined(PNG_WRITE_pHYs_SUPPORTED)
if (info->valid & PNG_INFO_pHYs)
png_write_pHYs(png_ptr, info->x_pixels_per_unit,
info->y_pixels_per_unit, info->phys_unit_type);
#endif
#if defined(PNG_WRITE_oFFs_SUPPORTED)
if (info->valid & PNG_INFO_oFFs)
png_write_oFFs(png_ptr, info->x_offset, info->y_offset,
info->offset_unit_type);
#endif
#if defined(PNG_WRITE_tIME_SUPPORTED)
if (info->valid & PNG_INFO_tIME)
png_write_tIME(png_ptr, &(info->mod_time));
/* 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)
{
@ -89,12 +84,6 @@ png_write_info(png_struct *png_ptr, png_info *info)
/* loop through the text chunks */
for (i = 0; i < info->num_text; i++)
{
if (strlen(info->text[i].key) > 80)
{
(*(png_ptr->warning_fn))(png_ptr,"tEXt keyword more than 80 chars");
continue;
}
/* if chunk is compressed */
if (info->text[i].compression >= 0)
{
@ -115,8 +104,7 @@ png_write_info(png_struct *png_ptr, png_info *info)
}
}
}
#endif /* PNG_WRITE_tEXt_SUPPORTED || PNG_WRITE_zTXt_SUPPORTED */
png_ptr->mode = PNG_HAVE_IHDR;
#endif
}
/* writes the end of the png file. If you don't want to write comments or
@ -124,11 +112,8 @@ png_write_info(png_struct *png_ptr, png_info *info)
in png_write_info(), do not write them again here. If you have long
comments, I suggest writing them here, and compressing them. */
void
png_write_end(png_struct *png_ptr, png_info *info)
png_write_end(png_structp png_ptr, png_infop info)
{
if (info && png_ptr->mode == PNG_AFTER_IEND)
return;
/* see if user wants us to write information chunks */
if (info)
{
@ -137,7 +122,6 @@ png_write_end(png_struct *png_ptr, png_info *info)
if (info->valid & PNG_INFO_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 */
if (info->num_text)
@ -167,17 +151,15 @@ png_write_end(png_struct *png_ptr, png_info *info)
}
}
}
#endif /* PNG_WRITE_tEXt_SUPPORTED || PNG_WRITE_zTXt_SUPPORTED */
#endif
}
/* write end of png file */
png_write_IEND(png_ptr);
png_ptr->mode = PNG_AFTER_IEND;
}
#if defined(PNG_WRITE_tIME_SUPPORTED)
void
png_convert_from_struct_tm(png_time *ptime, struct tm *ttime)
png_convert_from_struct_tm(png_timep ptime, struct tm FAR * ttime)
{
ptime->year = 1900 + ttime->tm_year;
ptime->month = ttime->tm_mon + 1;
@ -188,27 +170,37 @@ png_convert_from_struct_tm(png_time *ptime, struct tm *ttime)
}
void
png_convert_from_time_t(png_time *ptime, time_t ttime)
png_convert_from_time_t(png_timep ptime, time_t ttime)
{
struct tm *tbuf;
tbuf = gmtime(&ttime);
png_convert_from_struct_tm(ptime, tbuf);
}
#endif /* PNG_WRITE_tIME_SUPPORTED */
#endif
/* initialize png structure, and allocate any memory needed */
void
png_write_init(png_struct *png_ptr)
png_write_init(png_structp png_ptr)
{
jmp_buf tmp_jmp; /* to save current jump buffer */
png_msg_ptr error_fn;
png_msg_ptr warning_fn;
png_voidp msg_ptr;
/* save jump buffer */
/* save jump buffer and error functions */
png_memcpy(tmp_jmp, png_ptr->jmpbuf, sizeof (jmp_buf));
error_fn = png_ptr->error_fn;
warning_fn = png_ptr->warning_fn;
msg_ptr = png_ptr->msg_ptr;
/* reset all variables to 0 */
png_memset(png_ptr, 0, sizeof (png_struct));
/* restore jump buffer */
/* restore jump buffer and error functions */
png_memcpy(png_ptr->jmpbuf, tmp_jmp, sizeof (jmp_buf));
png_ptr->error_fn = error_fn;
png_ptr->warning_fn = warning_fn;
png_ptr->msg_ptr = msg_ptr;
/* initialize zbuf - compression buffer */
png_ptr->zbuf_size = PNG_ZBUF_SIZE;
@ -220,11 +212,11 @@ png_write_init(png_struct *png_ptr)
have called png_set_interlace_handling(), you will have to
"write" the image seven times */
void
png_write_rows(png_struct *png_ptr, png_bytef **row,
png_write_rows(png_structp png_ptr, png_bytepp row,
png_uint_32 num_rows)
{
png_uint_32 i; /* row counter */
png_bytef **rp; /* row pointer */
png_bytepp rp; /* row pointer */
/* loop through the rows */
for (i = 0, rp = row; i < num_rows; i++, rp++)
@ -236,11 +228,11 @@ png_write_rows(png_struct *png_ptr, png_bytef **row,
/* write the image. You only need to call this function once, even
if you are writing an interlaced image. */
void
png_write_image(png_struct *png_ptr, png_bytef **image)
png_write_image(png_structp png_ptr, png_bytepp image)
{
png_uint_32 i; /* row index */
int pass, num_pass; /* pass variables */
png_bytef **rp; /* points to current row */
png_bytepp rp; /* points to current row */
/* intialize interlace handling. If image is not interlaced,
this will set pass to 1 */
@ -258,16 +250,14 @@ png_write_image(png_struct *png_ptr, png_bytef **image)
/* write a row of image data */
void
png_write_row(png_struct *png_ptr, png_bytef *row)
png_write_row(png_structp png_ptr, png_bytep row)
{
/* initialize transformations and other stuff if first time */
if (png_ptr->mode < PNG_HAVE_IDAT)
if (png_ptr->row_number == 0 && png_ptr->pass == 0)
{
png_write_start_row(png_ptr);
}
png_ptr->mode = PNG_HAVE_IDAT;
#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
/* if interlaced and not interested in row, return */
if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
@ -325,7 +315,7 @@ png_write_row(png_struct *png_ptr, png_bytef *row)
break;
}
}
#endif /* PNG_WRITE_INTERLACE_SUPPORTED */
#endif
/* set up row info for transformations */
png_ptr->row_info.color_type = png_ptr->color_type;
@ -354,7 +344,7 @@ png_write_row(png_struct *png_ptr, png_bytef *row)
return;
}
}
#endif /* PNG_WRITE_INTERLACE_SUPPORTED */
#endif
/* handle other transformations */
if (png_ptr->transformations)
@ -373,7 +363,7 @@ png_write_row(png_struct *png_ptr, png_bytef *row)
/* trade saved pointer and prev pointer so next row references are correctly */
{ /* scope limiter */
png_bytef *tptr;
png_bytep tptr;
tptr = png_ptr->prev_row;
png_ptr->prev_row = png_ptr->save_row;
@ -387,7 +377,6 @@ png_write_row(png_struct *png_ptr, png_bytef *row)
/* set up the zlib input buffer */
png_ptr->zstream->next_in = png_ptr->row_buf;
png_ptr->zstream->avail_in = (uInt)png_ptr->row_info.rowbytes + 1;
/* repeat until we have compressed all the data */
do
{
@ -399,9 +388,9 @@ png_write_row(png_struct *png_ptr, png_bytef *row)
if (ret != Z_OK)
{
if (png_ptr->zstream->msg)
(*(png_ptr->error_fn))(png_ptr, png_ptr->zstream->msg);
png_error(png_ptr, png_ptr->zstream->msg);
else
(*(png_ptr->error_fn))(png_ptr, "zlib error");
png_error(png_ptr, "zlib error");
}
/* see if it is time to write another IDAT */
@ -441,7 +430,7 @@ png_set_flush(png_struct *png_ptr, int nrows)
void
png_write_flush(png_struct *png_ptr)
{
char wrote_IDAT;
int wrote_IDAT;
if (png_ptr->mode != PNG_HAVE_IDAT)
return;
@ -458,9 +447,9 @@ png_write_flush(png_struct *png_ptr)
if (ret != Z_OK)
{
if (png_ptr->zstream->msg)
(*(png_ptr->error_fn))(png_ptr, png_ptr->zstream->msg);
png_error(png_ptr, png_ptr->zstream->msg);
else
(*(png_ptr->error_fn))(png_ptr, "zlib error");
png_error(png_ptr, "zlib error");
}
if (!png_ptr->zstream->avail_out)
@ -484,18 +473,20 @@ png_write_flush(png_struct *png_ptr)
png_ptr->zstream->avail_out = (uInt)png_ptr->zbuf_size;
}
png_ptr->flush_rows = 0;
(*(png_ptr->output_flush_fn))(png_ptr);
png_flush(png_ptr);
}
#endif /* PNG_WRITE_FLUSH_SUPPORTED */
/* free any memory used in png struct */
void
png_write_destroy(png_struct *png_ptr)
png_write_destroy(png_structp png_ptr)
{
jmp_buf tmp_jmp; /* save jump buffer */
/* free any memory zlib uses */
deflateEnd(png_ptr->zstream);
png_free(png_ptr, png_ptr->zstream);
/* free our memory. png_free checks NULL for us. */
png_large_free(png_ptr, png_ptr->zbuf);
png_large_free(png_ptr, png_ptr->row_buf);
@ -506,44 +497,43 @@ png_write_destroy(png_struct *png_ptr)
png_memset(png_ptr, 0, sizeof (png_struct));
png_memcpy(png_ptr->jmpbuf, tmp_jmp, sizeof (jmp_buf));
}
void
png_set_filtering(png_struct *png_ptr, int filter)
png_set_filtering(png_structp 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_set_compression_level(png_structp 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_set_compression_mem_level(png_structp 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_set_compression_strategy(png_structp 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_set_compression_window_bits(png_structp 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_set_compression_method(png_structp png_ptr, int method)
{
png_ptr->zlib_custom_method = 1;
png_ptr->zlib_method = method;

39
pngwtran.c
View File

@ -1,10 +1,10 @@
/* pngwtran.c - transforms the data in a row for png writers
libpng 1.0 beta 2 - version 0.81
libpng 1.0 beta 2 - version 0.85
For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
August 24, 1995
December 19, 1995
*/
#define PNG_INTERNAL
@ -13,10 +13,10 @@
/* transform the data according to the users wishes. The order of
transformations is significant. */
void
png_do_write_transformations(png_struct *png_ptr)
png_do_write_transformations(png_structp png_ptr)
{
#if defined(PNG_WRITE_FILLER_SUPPORTED)
if (png_ptr->transformations & PNG_RGBA)
if (png_ptr->transformations & PNG_FILLER)
png_do_write_filler(&(png_ptr->row_info), png_ptr->row_buf + 1,
png_ptr->filler_loc);
#endif
@ -49,7 +49,7 @@ png_do_write_transformations(png_struct *png_ptr)
row_info bit depth should be 8 (one pixel per byte). The channels
should be 1 (this only happens on grayscale and paletted images) */
void
png_do_pack(png_row_info *row_info, png_bytef *row, png_byte bit_depth)
png_do_pack(png_row_infop row_info, png_bytep row, png_byte bit_depth)
{
if (row_info && row && row_info->bit_depth == 8 &&
row_info->channels == 1)
@ -58,8 +58,8 @@ png_do_pack(png_row_info *row_info, png_bytef *row, png_byte bit_depth)
{
case 1:
{
png_bytef *sp;
png_bytef *dp;
png_bytep sp;
png_bytep dp;
int mask;
png_int_32 i;
int v;
@ -89,8 +89,8 @@ png_do_pack(png_row_info *row_info, png_bytef *row, png_byte bit_depth)
}
case 2:
{
png_bytef *sp;
png_bytef *dp;
png_bytep sp;
png_bytep dp;
int shift;
png_int_32 i;
int v;
@ -121,8 +121,8 @@ png_do_pack(png_row_info *row_info, png_bytef *row, png_byte bit_depth)
}
case 4:
{
png_bytef *sp;
png_bytef *dp;
png_bytep sp;
png_bytep dp;
int shift;
png_int_32 i;
int v;
@ -170,7 +170,7 @@ png_do_pack(png_row_info *row_info, png_bytef *row, png_byte bit_depth)
would pass 3 as bit_depth, and this routine would translate the
data to 0 to 15. */
void
png_do_shift(png_row_info *row_info, png_bytef *row, png_color_8 *bit_depth)
png_do_shift(png_row_infop row_info, png_bytep row, png_color_8p bit_depth)
{
if (row && row_info &&
row_info->color_type != PNG_COLOR_TYPE_PALETTE)
@ -207,7 +207,7 @@ png_do_shift(png_row_info *row_info, png_bytef *row, png_color_8 *bit_depth)
/* with low row dephts, could only be grayscale, so one channel */
if (row_info->bit_depth < 8)
{
png_bytef *bp;
png_bytep bp;
png_uint_32 i;
int j;
png_byte mask;
@ -236,7 +236,7 @@ png_do_shift(png_row_info *row_info, png_bytef *row, png_color_8 *bit_depth)
}
else if (row_info->bit_depth == 8)
{
png_bytef *bp;
png_bytep bp;
png_uint_32 i;
int j;
@ -262,7 +262,7 @@ png_do_shift(png_row_info *row_info, png_bytef *row, png_color_8 *bit_depth)
}
else
{
png_bytef *bp;
png_bytep bp;
png_uint_32 i;
int j;
@ -297,7 +297,7 @@ png_do_shift(png_row_info *row_info, png_bytef *row, png_color_8 *bit_depth)
#ifdef PNG_WRITE_FILLER_SUPPORTED
/* remove filler byte */
void
png_do_write_filler(png_row_info *row_info, png_bytef *row,
png_do_write_filler(png_row_infop row_info, png_bytep row,
png_byte filler_loc)
{
if (row && row_info && row_info->color_type == PNG_COLOR_TYPE_RGB &&
@ -305,7 +305,8 @@ png_do_write_filler(png_row_info *row_info, png_bytef *row,
{
if (filler_loc == PNG_FILLER_AFTER)
{
png_bytef *sp, *dp;
png_bytep sp, dp;
png_uint_32 i;
for (i = 1, sp = row + 4, dp = row + 3;
@ -323,10 +324,10 @@ png_do_write_filler(png_row_info *row_info, png_bytef *row,
}
else
{
png_bytef *sp, *dp;
png_bytep sp, dp;
png_uint_32 i;
for (i = 1, sp = row + 4, dp = row + 3;
for (i = 0, sp = row, dp = row;
i < row_info->width;
i++)
{

161
pngwutil.c
View File

@ -1,10 +1,10 @@
/* pngwutil.c - utilities to write a png file
libpng 1.0 beta 2 - version 0.81
libpng 1.0 beta 2 - version 0.85
For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
August 24, 1995
December 19, 1995
*/
#define PNG_INTERNAL
#include "png.h"
@ -13,7 +13,7 @@
with unsigned numbers for convenience, you may have to cast
signed numbers (if you use any, most png data is unsigned). */
void
png_save_uint_32(png_byte *buf, png_uint_32 i)
png_save_uint_32(png_bytep buf, png_uint_32 i)
{
buf[0] = (png_byte)((i >> 24) & 0xff);
buf[1] = (png_byte)((i >> 16) & 0xff);
@ -23,7 +23,7 @@ png_save_uint_32(png_byte *buf, png_uint_32 i)
/* place a 16 bit number into a buffer in png byte order */
void
png_save_uint_16(png_byte *buf, png_uint_16 i)
png_save_uint_16(png_bytep buf, png_uint_16 i)
{
buf[0] = (png_byte)((i >> 8) & 0xff);
buf[1] = (png_byte)(i & 0xff);
@ -31,7 +31,7 @@ png_save_uint_16(png_byte *buf, png_uint_16 i)
/* write a 32 bit number */
void
png_write_uint_32(png_struct *png_ptr, png_uint_32 i)
png_write_uint_32(png_structp png_ptr, png_uint_32 i)
{
png_byte buf[4];
@ -39,18 +39,18 @@ png_write_uint_32(png_struct *png_ptr, png_uint_32 i)
buf[1] = (png_byte)((i >> 16) & 0xff);
buf[2] = (png_byte)((i >> 8) & 0xff);
buf[3] = (png_byte)(i & 0xff);
(*(png_ptr->write_data_fn))(png_ptr, buf, 4);
png_write_data(png_ptr, buf, 4);
}
/* write a 16 bit number */
void
png_write_uint_16(png_struct *png_ptr, png_uint_16 i)
png_write_uint_16(png_structp png_ptr, png_uint_16 i)
{
png_byte buf[2];
buf[0] = (png_byte)((i >> 8) & 0xff);
buf[1] = (png_byte)(i & 0xff);
(*(png_ptr->write_data_fn))(png_ptr, buf, 2);
png_write_data(png_ptr, buf, 2);
}
/* Write a png chunk all at once. The type is an array of ASCII characters
@ -62,13 +62,13 @@ png_write_uint_16(png_struct *png_ptr, png_uint_16 i)
png_write_chunk_start(), png_write_chunk_data(), and png_write_chunk_end()
functions instead. */
void
png_write_chunk(png_struct *png_ptr, png_byte *type,
png_bytef *data, png_uint_32 length)
png_write_chunk(png_structp png_ptr, png_bytep type,
png_bytep data, png_uint_32 length)
{
/* write length */
png_write_uint_32(png_ptr, length);
/* write chunk name */
(*(png_ptr->write_data_fn))(png_ptr, type, (png_uint_32)4);
png_write_data(png_ptr, type, (png_uint_32)4);
/* reset the crc and run the chunk name over it */
png_reset_crc(png_ptr);
png_calculate_crc(png_ptr, type, (png_uint_32)4);
@ -76,7 +76,7 @@ png_write_chunk(png_struct *png_ptr, png_byte *type,
if (length)
{
png_calculate_crc(png_ptr, data, length);
(*(png_ptr->write_data_fn))(png_ptr, data, length);
png_write_data(png_ptr, data, length);
}
/* write the crc */
png_write_uint_32(png_ptr, ~png_ptr->crc);
@ -86,13 +86,13 @@ png_write_chunk(png_struct *png_ptr, png_byte *type,
The total_length is the sum of the lengths of all the data you will be
passing in png_write_chunk_data() */
void
png_write_chunk_start(png_struct *png_ptr, png_byte *type,
png_write_chunk_start(png_structp png_ptr, png_bytep type,
png_uint_32 total_length)
{
/* write the length */
png_write_uint_32(png_ptr, total_length);
/* write the chunk name */
(*(png_ptr->write_data_fn))(png_ptr, type, (png_uint_32)4);
png_write_data(png_ptr, type, (png_uint_32)4);
/* reset the crc and run it over the chunk name */
png_reset_crc(png_ptr);
png_calculate_crc(png_ptr, type, (png_uint_32)4);
@ -103,19 +103,19 @@ 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
given to png_write_chunk_start() */
void
png_write_chunk_data(png_struct *png_ptr, png_bytef *data, png_uint_32 length)
png_write_chunk_data(png_structp png_ptr, png_bytep data, png_uint_32 length)
{
/* write the data, and run the crc over it */
if (length)
{
png_calculate_crc(png_ptr, data, length);
(*(png_ptr->write_data_fn))(png_ptr, data, length);
png_write_data(png_ptr, data, length);
}
}
/* finish a chunk started with png_write_chunk_start() */
void
png_write_chunk_end(png_struct *png_ptr)
png_write_chunk_end(png_structp png_ptr)
{
/* write the crc */
png_write_uint_32(png_ptr, ~png_ptr->crc);
@ -123,17 +123,17 @@ png_write_chunk_end(png_struct *png_ptr)
/* simple function to write the signature */
void
png_write_sig(png_struct *png_ptr)
png_write_sig(png_structp png_ptr)
{
/* write the 8 byte signature */
(*(png_ptr->write_data_fn))(png_ptr, png_sig, (png_uint_32)8);
png_write_data(png_ptr, png_sig, (png_uint_32)8);
}
/* Write the IHDR chunk, and update the png_struct with the necessary
information. Note that the rest of this code depends upon this
information being correct. */
void
png_write_IHDR(png_struct *png_ptr, png_uint_32 width, png_uint_32 height,
png_write_IHDR(png_structp png_ptr, png_uint_32 width, png_uint_32 height,
int bit_depth, int color_type, int compression_type, int filter_type,
int interlace_type)
{
@ -181,7 +181,7 @@ png_write_IHDR(png_struct *png_ptr, png_uint_32 width, png_uint_32 height,
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 = (z_stream *)png_malloc(png_ptr, sizeof (z_stream));
png_ptr->zstream->zalloc = png_zalloc;
png_ptr->zstream->zfree = png_zfree;
png_ptr->zstream->opaque = (voidp)png_ptr;
@ -221,10 +221,10 @@ png_write_IHDR(png_struct *png_ptr, png_uint_32 width, png_uint_32 height,
correct order for PNG, so people can redefine it to any convient
structure. */
void
png_write_PLTE(png_struct *png_ptr, png_color *palette, int number)
png_write_PLTE(png_structp png_ptr, png_colorp palette, int number)
{
int i;
png_color *pal_ptr;
png_colorp pal_ptr;
png_byte buf[3];
png_write_chunk_start(png_ptr, png_PLTE, number * 3);
@ -242,14 +242,14 @@ png_write_PLTE(png_struct *png_ptr, png_color *palette, int number)
/* write an IDAT chunk */
void
png_write_IDAT(png_struct *png_ptr, png_bytef *data, png_uint_32 length)
png_write_IDAT(png_structp png_ptr, png_bytep data, png_uint_32 length)
{
png_write_chunk(png_ptr, png_IDAT, data, length);
}
/* write an IEND chunk */
void
png_write_IEND(png_struct *png_ptr)
png_write_IEND(png_structp png_ptr)
{
png_write_chunk(png_ptr, png_IEND, NULL, (png_uint_32)0);
}
@ -257,7 +257,7 @@ png_write_IEND(png_struct *png_ptr)
#if defined(PNG_WRITE_gAMA_SUPPORTED)
/* write a gAMA chunk */
void
png_write_gAMA(png_struct *png_ptr, float gamma)
png_write_gAMA(png_structp png_ptr, double gamma)
{
png_uint_32 igamma;
png_byte buf[4];
@ -272,12 +272,12 @@ png_write_gAMA(png_struct *png_ptr, float gamma)
#if defined(PNG_WRITE_sBIT_SUPPORTED)
/* write the sBIT chunk */
void
png_write_sBIT(png_struct *png_ptr, png_color_8 *sbit, int color_type)
png_write_sBIT(png_structp png_ptr, png_color_8p sbit, int color_type)
{
png_byte buf[4];
int size;
/* make sure we don't depend upon the order of png_color_8 */
/* make sure we don't depend upon the order of PNG_COLOR_8 */
if (color_type & PNG_COLOR_MASK_COLOR)
{
buf[0] = sbit->red;
@ -303,9 +303,9 @@ png_write_sBIT(png_struct *png_ptr, png_color_8 *sbit, int color_type)
#if defined(PNG_WRITE_cHRM_SUPPORTED)
/* write the cHRM chunk */
void
png_write_cHRM(png_struct *png_ptr, float white_x, float white_y,
float red_x, float red_y, float green_x, float green_y,
float blue_x, float blue_y)
png_write_cHRM ( png_structp png_ptr, double white_x, double white_y,
double red_x, double red_y, double green_x, double green_y,
double blue_x, double blue_y)
{
png_uint_32 itemp;
png_byte buf[32];
@ -334,7 +334,7 @@ png_write_cHRM(png_struct *png_ptr, float white_x, float white_y,
#if defined(PNG_WRITE_tRNS_SUPPORTED)
/* write the tRNS chunk */
void
png_write_tRNS(png_struct *png_ptr, png_byte *trans, png_color_16 *tran,
png_write_tRNS(png_structp png_ptr, png_bytep trans, png_color_16p tran,
int num_trans, int color_type)
{
png_byte buf[6];
@ -364,7 +364,7 @@ png_write_tRNS(png_struct *png_ptr, png_byte *trans, png_color_16 *tran,
#if defined(PNG_WRITE_bKGD_SUPPORTED)
/* write the background chunk */
void
png_write_bKGD(png_struct *png_ptr, png_color_16 *back, int color_type)
png_write_bKGD(png_structp png_ptr, png_color_16p back, int color_type)
{
png_byte buf[6];
@ -391,7 +391,7 @@ png_write_bKGD(png_struct *png_ptr, png_color_16 *back, int color_type)
#if defined(PNG_WRITE_hIST_SUPPORTED)
/* write the histogram */
void
png_write_hIST(png_struct *png_ptr, png_uint_16 *hist, int number)
png_write_hIST(png_structp png_ptr, png_uint_16p hist, int number)
{
int i;
png_byte buf[3];
@ -409,7 +409,7 @@ png_write_hIST(png_struct *png_ptr, png_uint_16 *hist, int number)
#if defined(PNG_WRITE_tEXt_SUPPORTED)
/* write a tEXt chunk */
void
png_write_tEXt(png_struct *png_ptr, charf *key, charf *text,
png_write_tEXt(png_structp png_ptr, png_charp key, png_charp text,
png_uint_32 text_len)
{
int key_len;
@ -419,9 +419,9 @@ png_write_tEXt(png_struct *png_ptr, charf *key, charf *text,
png_write_chunk_start(png_ptr, png_tEXt,
(png_uint_32)(key_len + text_len + 1));
/* key has an 0 at the end. How nice */
png_write_chunk_data(png_ptr, (png_bytef *)key, (png_uint_32)(key_len + 1));
png_write_chunk_data(png_ptr, (png_bytep )key, (png_uint_32)(key_len + 1));
if (text && text_len)
png_write_chunk_data(png_ptr, (png_bytef *)text, (png_uint_32)text_len);
png_write_chunk_data(png_ptr, (png_bytep )text, (png_uint_32)text_len);
png_write_chunk_end(png_ptr);
}
#endif
@ -429,13 +429,13 @@ png_write_tEXt(png_struct *png_ptr, charf *key, charf *text,
#if defined(PNG_WRITE_zTXt_SUPPORTED)
/* write a compressed chunk */
void
png_write_zTXt(png_struct *png_ptr, charf *key, charf *text,
png_write_zTXt(png_structp png_ptr, png_charp key, png_charp text,
png_uint_32 text_len, int compression)
{
int key_len;
char buf[1];
int i, ret;
charf **output_ptr = NULL; /* array of pointers to output */
png_charpp output_ptr = NULL; /* array of pointers to output */
int num_output_ptr = 0; /* number of output pointers used */
int max_output_ptr = 0; /* size of output_ptr */
@ -462,9 +462,9 @@ png_write_zTXt(png_struct *png_ptr, charf *key, charf *text,
{
/* error */
if (png_ptr->zstream->msg)
(*(png_ptr->error_fn))(png_ptr, png_ptr->zstream->msg);
png_error(png_ptr, png_ptr->zstream->msg);
else
(*(png_ptr->error_fn))(png_ptr, "zlib error");
png_error(png_ptr, "zlib error");
}
/* check to see if we need more room */
if (!png_ptr->zstream->avail_out && png_ptr->zstream->avail_in)
@ -477,12 +477,12 @@ png_write_zTXt(png_struct *png_ptr, charf *key, charf *text,
old_max = max_output_ptr;
max_output_ptr = num_output_ptr + 4;
if (output_ptr)
output_ptr = png_realloc(png_ptr, output_ptr,
max_output_ptr * sizeof (char *),
old_max * sizeof (char *));
output_ptr = (png_charpp)png_realloc(png_ptr, output_ptr,
max_output_ptr * sizeof (png_charpp),
old_max * sizeof (png_charp));
else
output_ptr = png_malloc(png_ptr,
max_output_ptr * sizeof (char *));
output_ptr = (png_charpp)png_malloc(png_ptr,
max_output_ptr * sizeof (png_charp));
}
/* save the data */
@ -508,9 +508,9 @@ png_write_zTXt(png_struct *png_ptr, charf *key, charf *text,
{
/* we got an error */
if (png_ptr->zstream->msg)
(*(png_ptr->error_fn))(png_ptr, png_ptr->zstream->msg);
png_error(png_ptr, png_ptr->zstream->msg);
else
(*(png_ptr->error_fn))(png_ptr, "zlib error");
png_error(png_ptr, "zlib error");
}
/* check to see if we need more room */
@ -524,12 +524,12 @@ png_write_zTXt(png_struct *png_ptr, charf *key, charf *text,
old_max = max_output_ptr;
max_output_ptr = num_output_ptr + 4;
if (output_ptr)
output_ptr = png_realloc(png_ptr, output_ptr,
max_output_ptr * sizeof (char *),
old_max * sizeof (char *));
output_ptr = (png_charpp)png_realloc(png_ptr, output_ptr,
max_output_ptr * sizeof (png_charp),
old_max * sizeof (png_charp));
else
output_ptr = png_malloc(png_ptr,
max_output_ptr * sizeof (char *));
output_ptr = (png_charpp)png_malloc(png_ptr,
max_output_ptr * sizeof (png_charp));
}
/* save off the data */
@ -555,15 +555,15 @@ png_write_zTXt(png_struct *png_ptr, charf *key, charf *text,
png_write_chunk_start(png_ptr, png_zTXt,
(png_uint_32)(key_len + text_len + 2));
/* write key */
png_write_chunk_data(png_ptr, (png_bytef *)key, (png_uint_32)(key_len + 1));
png_write_chunk_data(png_ptr, (png_bytep )key, (png_uint_32)(key_len + 1));
buf[0] = compression;
/* write compression */
png_write_chunk_data(png_ptr, (png_byte *)buf, (png_uint_32)1);
png_write_chunk_data(png_ptr, (png_bytep )buf, (png_uint_32)1);
/* write saved output buffers, if any */
for (i = 0; i < num_output_ptr; i++)
{
png_write_chunk_data(png_ptr, (png_bytef *)output_ptr[i], png_ptr->zbuf_size);
png_write_chunk_data(png_ptr, (png_bytep )output_ptr[i], png_ptr->zbuf_size);
png_large_free(png_ptr, output_ptr[i]);
}
if (max_output_ptr)
@ -583,7 +583,7 @@ png_write_zTXt(png_struct *png_ptr, charf *key, charf *text,
#if defined(PNG_WRITE_pHYs_SUPPORTED)
/* write the pHYs chunk */
void
png_write_pHYs(png_struct *png_ptr, png_uint_32 x_pixels_per_unit,
png_write_pHYs(png_structp png_ptr, png_uint_32 x_pixels_per_unit,
png_uint_32 y_pixels_per_unit,
int unit_type)
{
@ -600,7 +600,7 @@ png_write_pHYs(png_struct *png_ptr, png_uint_32 x_pixels_per_unit,
#if defined(PNG_WRITE_oFFs_SUPPORTED)
/* write the oFFs chunk */
void
png_write_oFFs(png_struct *png_ptr, png_uint_32 x_offset,
png_write_oFFs(png_structp png_ptr, png_uint_32 x_offset,
png_uint_32 y_offset,
int unit_type)
{
@ -618,7 +618,7 @@ png_write_oFFs(png_struct *png_ptr, png_uint_32 x_offset,
/* write the tIME chunk. Use either png_convert_from_struct_tm()
or png_convert_from_time_t(), or fill in the structure yourself */
void
png_write_tIME(png_struct *png_ptr, png_time *mod_time)
png_write_tIME(png_structp png_ptr, png_timep mod_time)
{
png_byte buf[7];
@ -635,20 +635,20 @@ png_write_tIME(png_struct *png_ptr, png_time *mod_time)
/* initializes the row writing capability of libpng */
void
png_write_start_row(png_struct *png_ptr)
png_write_start_row(png_structp png_ptr)
{
/* set up row buffer */
png_ptr->row_buf = (png_bytef *)png_large_malloc(png_ptr,
png_ptr->row_buf = (png_bytep )png_large_malloc(png_ptr,
(((png_uint_32)png_ptr->usr_channels *
(png_uint_32)png_ptr->usr_bit_depth *
png_ptr->width) >> 3) + 1);
png_ptr->width + 7) >> 3) + 1);
/* set up filtering buffers, if filtering */
if (png_ptr->do_filter)
{
png_ptr->prev_row = (png_bytef *)png_large_malloc(png_ptr,
png_ptr->prev_row = (png_bytep )png_large_malloc(png_ptr,
png_ptr->rowbytes + 1);
png_memset(png_ptr->prev_row, 0, (png_size_t)png_ptr->rowbytes + 1);
png_ptr->save_row = (png_bytef *)png_large_malloc(png_ptr,
png_ptr->save_row = (png_bytep )png_large_malloc(png_ptr,
png_ptr->rowbytes + 1);
png_memset(png_ptr->save_row, 0, (png_size_t)png_ptr->rowbytes + 1);
}
@ -682,14 +682,14 @@ png_write_start_row(png_struct *png_ptr)
/* Internal use only. Called when finished processing a row of data */
void
png_write_finish_row(png_struct *png_ptr)
png_write_finish_row(png_structp png_ptr)
{
int ret;
/* next row */
png_ptr->row_number++;
/* see if we are done */
if (png_ptr->row_number < png_ptr->num_rows || png_ptr->mode > PNG_HAVE_IDAT)
if (png_ptr->row_number < png_ptr->num_rows)
return;
/* if interlaced, go to next pass */
@ -740,9 +740,9 @@ png_write_finish_row(png_struct *png_ptr)
if (ret != Z_OK && ret != Z_STREAM_END)
{
if (png_ptr->zstream->msg)
(*(png_ptr->error_fn))(png_ptr, png_ptr->zstream->msg);
png_error(png_ptr, png_ptr->zstream->msg);
else
(*(png_ptr->error_fn))(png_ptr, "zlib error");
png_error(png_ptr, "zlib error");
}
/* check to see if we need more room */
if (!png_ptr->zstream->avail_out && ret == Z_OK)
@ -761,7 +761,6 @@ png_write_finish_row(png_struct *png_ptr)
}
deflateReset(png_ptr->zstream);
png_ptr->mode = PNG_AFTER_IDAT;
}
#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
@ -774,7 +773,7 @@ png_write_finish_row(png_struct *png_ptr)
See the default: case for the easiest code to understand.
*/
void
png_do_write_interlace(png_row_info *row_info, png_bytef *row, int pass)
png_do_write_interlace(png_row_infop row_info, png_bytep row, int pass)
{
/* we don't have to do anything on the last pass (6) */
if (row && row_info && pass < 6)
@ -784,8 +783,8 @@ png_do_write_interlace(png_row_info *row_info, png_bytef *row, int pass)
{
case 1:
{
png_bytef *sp;
png_bytef *dp;
png_bytep sp;
png_bytep dp;
int shift;
int d;
int value;
@ -818,8 +817,8 @@ png_do_write_interlace(png_row_info *row_info, png_bytef *row, int pass)
}
case 2:
{
png_bytef *sp;
png_bytef *dp;
png_bytep sp;
png_bytep dp;
int shift;
int d;
int value;
@ -851,8 +850,8 @@ png_do_write_interlace(png_row_info *row_info, png_bytef *row, int pass)
}
case 4:
{
png_bytef *sp;
png_bytef *dp;
png_bytep sp;
png_bytep dp;
int shift;
int d;
int value;
@ -884,8 +883,8 @@ png_do_write_interlace(png_row_info *row_info, png_bytef *row, int pass)
}
default:
{
png_bytef *sp;
png_bytef *dp;
png_bytep sp;
png_bytep dp;
png_uint_32 i;
int pixel_bytes;
@ -925,13 +924,13 @@ png_do_write_interlace(png_row_info *row_info, png_bytef *row, int pass)
/* this filters the row. Both row and prev_row have space at the
first byte for the filter byte. */
void
png_write_filter_row(png_row_info *row_info, png_bytef *row,
png_bytef *prev_row)
png_write_filter_row(png_row_infop row_info, png_bytep row,
png_bytep prev_row)
{
int minf, bpp;
png_uint_32 i, v;
png_uint_32 s0, s1, s2, s3, s4, mins;
png_bytef *rp, *pp, *cp, *lp;
png_bytep rp, pp, cp, lp;
/* find out how many bytes offset each pixel is */
bpp = (row_info->pixel_depth + 7) / 8;

41
readme.txt
View File

@ -1,31 +1,28 @@
readme.txt - for libpng 0.8
readme.txt - for libpng 0.85
This is the second beta version of libpng 1.0. I've updated most
of the stuff I want to before the final 1.0 version. Remaining
to do are the medium memory model support (which I'll put in
as soon as we test this version), better dithering, and any bug
fixes and makefile/include additions. I expect a third (and
perhaps final) beta after zlib is officially 1.0.
This is a bug fix for the second beta version of libpng 1.0, and
a first try at a progressive (push) reader. It hasn't been
tested very much, but I'm not going to have time to test it for
a few days, and I wanted to give an advanced look at the
progressive reader to everyone. Please report bugs back
(and fixes, if you find them), and I'll release a new version
in a week or two. Thanks.
I've implemented the callback functions for the error/warning
messages and the input/output. See the libpng.txt
for details. I've also added defines to support medium memory
models, so every type now has pointer defines. For example,
a pointer to the png_struct is now png_structp, while a double
pointer is now png_structpp. The old way should work, but I'll
be using the new way from now on in all my examples. Those of
you doing medium memory model or changing the error/warning
or input/output functions should try these and report back to
me any problems.
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
usage information and restrictions (what little they are) on libpng,
see png.h. For a description on using zlib (the compression library