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Imported from libpng-1.2.37beta03.tar

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This commit is contained in:
Glenn Randers-Pehrson
2009-05-20 12:43:52 -05:00
parent c0d53e176b
commit e5ee05dc0d
66 changed files with 1969 additions and 1613 deletions
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142
example.c
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@@ -2,7 +2,7 @@
#if 0 /* in case someone actually tries to compile this */
/* example.c - an example of using libpng
* Last changed in libpng 1.2.37 [May 19, 2009]
* Last changed in libpng 1.2.37 [May 20, 2009]
* This file has been placed in the public domain by the authors.
* Maintained 1998-2009 Glenn Randers-Pehrson
* Maintained 1996, 1997 Andreas Dilger)
@@ -93,13 +93,13 @@ void read_png(char *file_name) /* We need to open the file */
return (ERROR);
#else no_open_file /* prototype 2 */
void read_png(FILE *fp, unsigned int sig_read) /* file is already open */
void read_png(FILE *fp, unsigned int sig_read) /* File is already open */
{
png_structp png_ptr;
png_infop info_ptr;
png_uint_32 width, height;
int bit_depth, color_type, interlace_type;
#endif no_open_file /* only use one prototype! */
#endif no_open_file /* Only use one prototype! */
/* Create and initialize the png_struct with the desired error handler
* functions. If you want to use the default stderr and longjump method,
@@ -177,11 +177,11 @@ void read_png(FILE *fp, unsigned int sig_read) /* file is already open */
png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
&interlace_type, int_p_NULL, int_p_NULL);
/* Set up the data transformations you want. Note that these are all
* optional. Only call them if you want/need them. Many of the
* transformations only work on specific types of images, and many
* are mutually exclusive.
*/
/* Set up the data transformations you want. Note that these are all
* optional. Only call them if you want/need them. Many of the
* transformations only work on specific types of images, and many
* are mutually exclusive.
*/
/* Tell libpng to strip 16 bit/color files down to 8 bits/color */
png_set_strip_16(png_ptr);
@@ -230,9 +230,9 @@ void read_png(FILE *fp, unsigned int sig_read) /* file is already open */
png_set_background(png_ptr, &my_background,
PNG_BACKGROUND_GAMMA_SCREEN, 0, 1.0);
/* Some suggestions as to how to get a screen gamma value */
/* Note that screen gamma is the display_exponent, which includes
/* Some suggestions as to how to get a screen gamma value
*
* Note that screen gamma is the display_exponent, which includes
* the CRT_exponent and any correction for viewing conditions
*/
if (/* We have a user-defined screen gamma value */)
@@ -280,7 +280,7 @@ void read_png(FILE *fp, unsigned int sig_read) /* file is already open */
png_colorp palette;
/* This reduces the image to the application supplied palette */
if (/* we have our own palette */)
if (/* We have our own palette */)
{
/* An array of colors to which the image should be dithered */
png_color std_color_cube[MAX_SCREEN_COLORS];
@@ -377,13 +377,13 @@ void read_png(FILE *fp, unsigned int sig_read) /* file is already open */
#else no_sparkle /* Read the image using the "rectangle" effect */
png_read_rows(png_ptr, png_bytepp_NULL, &row_pointers[y],
number_of_rows);
#endif no_sparkle /* use only one of these two methods */
#endif no_sparkle /* Use only one of these two methods */
}
/* if you want to display the image after every pass, do so here */
#endif no_single /* use only one of these two methods */
/* If you want to display the image after every pass, do so here */
#endif no_single /* Use only one of these two methods */
}
#endif no_entire /* use only one of these two methods */
#endif no_entire /* Use only one of these two methods */
/* Read rest of file, and get additional chunks in info_ptr - REQUIRED */
png_read_end(png_ptr, info_ptr);
@@ -397,7 +397,7 @@ void read_png(FILE *fp, unsigned int sig_read) /* file is already open */
/* Close the file */
fclose(fp);
/* that's it */
/* That's it */
return (OK);
}
@@ -480,34 +480,35 @@ process_data(png_structp *png_ptr, png_infop *info_ptr,
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.
*/
/* 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 interlaced, and you turned on the interlace handler,
* this function will be called for every row in every pass.
*
* In this function you will receive a pointer to new row data from
* libpng called new_row that is to replace a corresponding row (of
* the same data format) in a buffer allocated by your application.
*
* The new row data pointer "new_row" may be NULL, indicating there is
* no new data to be replaced (in cases of interlace loading).
*
* If new_row is not NULL then you need to call
* png_progressive_combine_row() to replace the corresponding row as
* shown below:
*/
/*
* This function is called for every row in the image. If the
* image is interlaced, and you turned on the interlace handler,
* this function will be called for every row in every pass.
*
* In this function you will receive a pointer to new row data from
* libpng called new_row that is to replace a corresponding row (of
* the same data format) in a buffer allocated by your application.
*
* The new row data pointer "new_row" may be NULL, indicating there is
* no new data to be replaced (in cases of interlace loading).
*
* If new_row is not NULL then you need to call
* png_progressive_combine_row() to replace the corresponding row as
* shown below:
*/
/* Check if row_num is in bounds. */
if ((row_num >= 0) && (row_num < height))
{
@@ -522,41 +523,41 @@ row_callback(png_structp png_ptr, png_bytep new_row,
if ((old_row != NULL) && (new_row != NULL))
png_progressive_combine_row(png_ptr, old_row, new_row);
}
/*
* 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 new row and the
* old row, as demonstrated above. You can call this function for
* NULL rows (it will just return) and for non-interlaced images
* (it just does the png_memcpy for you) if it will make the code
* easier. Thus, you can just do this for all cases:
*/
/*
* 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 new row and the
* old row, as demonstrated above. You can call this function for
* NULL rows (it will just return) and for non-interlaced images
* (it just does the png_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 as new_row, and the function will combine
* the old row and the 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 as new_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.
*/
/* 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 */
@@ -608,6 +609,7 @@ void write_png(char *file_name /* , ... other image information ... */)
}
/* One of the following I/O initialization functions is REQUIRED */
#ifdef streams /* I/O initialization method 1 */
/* Set up the output control if you are using standard C streams */
png_init_io(png_ptr, fp);
@@ -619,7 +621,7 @@ void write_png(char *file_name /* , ... other image information ... */)
png_set_write_fn(png_ptr, (void *)user_io_ptr, user_write_fn,
user_IO_flush_function);
/* where user_io_ptr is a structure you want available to the callbacks */
#endif no_streams /* only use one initialization method */
#endif no_streams /* Only use one initialization method */
#ifdef hilevel
/* This is the easy way. Use it if you already have all the
@@ -771,7 +773,7 @@ void write_png(char *file_name /* , ... other image information ... */)
#ifdef entire /* Write out the entire image data in one call */
png_write_image(png_ptr, row_pointers);
/* the other way to write the image - deal with interlacing */
/* The other way to write the image - deal with interlacing */
#else no_entire /* Write out the image data by one or more scanlines */