forked from AuroraMiddleware/gtk
0eb096334e
1999-10-27 Federico Mena Quintero <federico@redhat.com> * src/gdk-pixbuf-render.c (gdk_pixbuf_render_threshold_alpha): New function to threshold a pixbuf's alpha channel into a bitmap. * src/gdk-pixbuf.c (gdk_pixbuf_new): Fixed so that it will contemplate future extensions to ArtPixBuf's formats. * src/io-png.c (png_info_callback): Use the new API of gdk_pixbuf_new(). * src/gdk-pixbuf.h (gdk_pixbuf_get_height): Added some convenience macros to fetch the ArtPixBuf's fields.
440 lines
12 KiB
C
440 lines
12 KiB
C
/* GdkPixbuf library - JPEG image loader
|
||
*
|
||
* Copyright (C) 1999 Mark Crichton
|
||
* Copyright (C) 1999 The Free Software Foundation
|
||
*
|
||
* Authors: Mark Crichton <crichton@gimp.org>
|
||
* Federico Mena-Quintero <federico@gimp.org>
|
||
*
|
||
* This library is free software; you can redistribute it and/or
|
||
* modify it under the terms of the GNU Library General Public
|
||
* License as published by the Free Software Foundation; either
|
||
* version 2 of the License, or (at your option) any later version.
|
||
*
|
||
* This library is distributed in the hope that it will be useful,
|
||
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||
* Library General Public License for more details.
|
||
*
|
||
* You should have received a copy of the GNU Library General Public
|
||
* License along with this library; if not, write to the
|
||
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
|
||
* Boston, MA 02111-1307, USA.
|
||
*/
|
||
|
||
#include <config.h>
|
||
#include <stdio.h>
|
||
#include <png.h>
|
||
#include "gdk-pixbuf.h"
|
||
#include "gdk-pixbuf-io.h"
|
||
|
||
|
||
|
||
static void
|
||
setup_png_transformations(png_structp png_read_ptr, png_infop png_info_ptr,
|
||
gboolean *fatal_error_occurred,
|
||
png_uint_32* width_p, png_uint_32* height_p,
|
||
int* color_type_p)
|
||
{
|
||
png_uint_32 width, height;
|
||
int bit_depth, color_type, interlace_type, compression_type, filter_type;
|
||
int channels;
|
||
|
||
/* Get the image info */
|
||
|
||
png_get_IHDR (png_read_ptr, png_info_ptr,
|
||
&width, &height,
|
||
&bit_depth,
|
||
&color_type,
|
||
&interlace_type,
|
||
&compression_type,
|
||
&filter_type);
|
||
|
||
/* set_expand() basically needs to be called unless
|
||
we are already in RGB/RGBA mode
|
||
*/
|
||
if (color_type == PNG_COLOR_TYPE_PALETTE &&
|
||
bit_depth <= 8) {
|
||
|
||
/* Convert indexed images to RGB */
|
||
png_set_expand (png_read_ptr);
|
||
|
||
} else if (color_type == PNG_COLOR_TYPE_GRAY &&
|
||
bit_depth < 8) {
|
||
|
||
/* Convert grayscale to RGB */
|
||
png_set_expand (png_read_ptr);
|
||
|
||
} else if (png_get_valid (png_read_ptr,
|
||
png_info_ptr, PNG_INFO_tRNS)) {
|
||
|
||
/* If we have transparency header, convert it to alpha
|
||
channel */
|
||
png_set_expand(png_read_ptr);
|
||
|
||
} else if (bit_depth < 8) {
|
||
|
||
/* If we have < 8 scale it up to 8 */
|
||
png_set_expand(png_read_ptr);
|
||
|
||
|
||
/* Conceivably, png_set_packing() is a better idea;
|
||
* God only knows how libpng works
|
||
*/
|
||
}
|
||
|
||
/* If we are 16-bit, convert to 8-bit */
|
||
if (bit_depth == 16) {
|
||
png_set_strip_16(png_read_ptr);
|
||
}
|
||
|
||
/* If gray scale, convert to RGB */
|
||
if (color_type == PNG_COLOR_TYPE_GRAY ||
|
||
color_type == PNG_COLOR_TYPE_GRAY_ALPHA) {
|
||
png_set_gray_to_rgb(png_read_ptr);
|
||
}
|
||
|
||
/* If interlaced, handle that */
|
||
if (interlace_type != PNG_INTERLACE_NONE) {
|
||
png_set_interlace_handling(png_read_ptr);
|
||
}
|
||
|
||
/* Update the info the reflect our transformations */
|
||
png_read_update_info(png_read_ptr, png_info_ptr);
|
||
|
||
png_get_IHDR (png_read_ptr, png_info_ptr,
|
||
&width, &height,
|
||
&bit_depth,
|
||
&color_type,
|
||
&interlace_type,
|
||
&compression_type,
|
||
&filter_type);
|
||
|
||
*width_p = width;
|
||
*height_p = height;
|
||
*color_type_p = color_type;
|
||
|
||
#ifndef G_DISABLE_CHECKS
|
||
/* Check that the new info is what we want */
|
||
|
||
if (bit_depth != 8) {
|
||
g_warning("Bits per channel of transformed PNG is %d, not 8.", bit_depth);
|
||
*fatal_error_occurred = TRUE;
|
||
return;
|
||
}
|
||
|
||
if ( ! (color_type == PNG_COLOR_TYPE_RGB ||
|
||
color_type == PNG_COLOR_TYPE_RGB_ALPHA) ) {
|
||
g_warning("Transformed PNG not RGB or RGBA.");
|
||
*fatal_error_occurred = TRUE;
|
||
return;
|
||
}
|
||
|
||
channels = png_get_channels(png_read_ptr, png_info_ptr);
|
||
if ( ! (channels == 3 || channels == 4) ) {
|
||
g_warning("Transformed PNG has %d channels, must be 3 or 4.", channels);
|
||
*fatal_error_occurred = TRUE;
|
||
return;
|
||
}
|
||
#endif
|
||
}
|
||
|
||
/* Destroy notification function for the libart pixbuf */
|
||
static void
|
||
free_buffer (gpointer user_data, gpointer data)
|
||
{
|
||
free (data);
|
||
}
|
||
|
||
/* Shared library entry point */
|
||
GdkPixbuf *
|
||
image_load (FILE *f)
|
||
{
|
||
png_structp png_ptr;
|
||
png_infop info_ptr, end_info;
|
||
gboolean failed = FALSE;
|
||
gint i, ctype, bpp;
|
||
png_uint_32 w, h;
|
||
png_bytepp rows;
|
||
guchar *pixels;
|
||
|
||
png_ptr = png_create_read_struct (PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
|
||
if (!png_ptr)
|
||
return NULL;
|
||
|
||
info_ptr = png_create_info_struct (png_ptr);
|
||
if (!info_ptr) {
|
||
png_destroy_read_struct (&png_ptr, NULL, NULL);
|
||
return NULL;
|
||
}
|
||
|
||
end_info = png_create_info_struct (png_ptr);
|
||
if (!end_info) {
|
||
png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
|
||
return NULL;
|
||
}
|
||
|
||
if (setjmp (png_ptr->jmpbuf)) {
|
||
png_destroy_read_struct (&png_ptr, &info_ptr, &end_info);
|
||
return NULL;
|
||
}
|
||
|
||
png_init_io (png_ptr, f);
|
||
png_read_info (png_ptr, info_ptr);
|
||
|
||
setup_png_transformations(png_ptr, info_ptr, &failed, &w, &h, &ctype);
|
||
|
||
if (failed) {
|
||
png_destroy_read_struct (&png_ptr, &info_ptr, &end_info);
|
||
return NULL;
|
||
}
|
||
|
||
if (ctype & PNG_COLOR_MASK_ALPHA)
|
||
bpp = 4;
|
||
else
|
||
bpp = 3;
|
||
|
||
pixels = malloc (w * h * bpp);
|
||
if (!pixels) {
|
||
png_destroy_read_struct (&png_ptr, &info_ptr, &end_info);
|
||
return NULL;
|
||
}
|
||
|
||
rows = g_new (png_bytep, h);
|
||
|
||
for (i = 0; i < h; i++)
|
||
rows[i] = pixels + i * w * bpp;
|
||
|
||
png_read_image (png_ptr, rows);
|
||
png_destroy_read_struct (&png_ptr, &info_ptr, &end_info);
|
||
g_free (rows);
|
||
|
||
if (ctype & PNG_COLOR_MASK_ALPHA)
|
||
return gdk_pixbuf_new_from_data (pixels, ART_PIX_RGB, TRUE,
|
||
w, h, w * 4,
|
||
free_buffer, NULL);
|
||
else
|
||
return gdk_pixbuf_new_from_data (pixels, ART_PIX_RGB, FALSE,
|
||
w, h, w * 3,
|
||
free_buffer, NULL);
|
||
}
|
||
|
||
/* These avoid the setjmp()/longjmp() crap in libpng */
|
||
static void png_error_callback (png_structp png_read_ptr,
|
||
png_const_charp error_msg);
|
||
|
||
static void png_warning_callback(png_structp png_read_ptr,
|
||
png_const_charp warning_msg);
|
||
|
||
/* Called at the start of the progressive load */
|
||
static void png_info_callback (png_structp png_read_ptr,
|
||
png_infop png_info_ptr);
|
||
|
||
/* Called for each row; note that you will get duplicate row numbers
|
||
for interlaced PNGs */
|
||
static void png_row_callback (png_structp png_read_ptr,
|
||
png_bytep new_row,
|
||
png_uint_32 row_num,
|
||
int pass_num);
|
||
|
||
/* Called after reading the entire image */
|
||
static void png_end_callback (png_structp png_read_ptr,
|
||
png_infop png_info_ptr);
|
||
|
||
typedef struct _LoadContext LoadContext;
|
||
|
||
struct _LoadContext {
|
||
png_structp png_read_ptr;
|
||
png_infop png_info_ptr;
|
||
|
||
ModulePreparedNotifyFunc notify_func;
|
||
gpointer notify_user_data;
|
||
|
||
GdkPixbuf* pixbuf;
|
||
|
||
guint fatal_error_occurred : 1;
|
||
|
||
};
|
||
|
||
gpointer
|
||
image_begin_load (ModulePreparedNotifyFunc func, gpointer user_data)
|
||
{
|
||
LoadContext* lc;
|
||
|
||
lc = g_new0(LoadContext, 1);
|
||
|
||
lc->fatal_error_occurred = FALSE;
|
||
|
||
lc->notify_func = func;
|
||
lc->notify_user_data = user_data;
|
||
|
||
/* Create the main PNG context struct */
|
||
|
||
lc->png_read_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,
|
||
lc, /* error/warning callback data */
|
||
png_error_callback,
|
||
png_warning_callback);
|
||
|
||
if (lc->png_read_ptr == NULL) {
|
||
g_free(lc);
|
||
return NULL;
|
||
}
|
||
|
||
/* Create the auxiliary context struct */
|
||
|
||
lc->png_info_ptr = png_create_info_struct(lc->png_read_ptr);
|
||
|
||
if (lc->png_info_ptr == NULL) {
|
||
png_destroy_read_struct(&lc->png_read_ptr, NULL, NULL);
|
||
g_free(lc);
|
||
return NULL;
|
||
}
|
||
|
||
png_set_progressive_read_fn(lc->png_read_ptr,
|
||
lc, /* callback data */
|
||
png_info_callback,
|
||
png_row_callback,
|
||
png_end_callback);
|
||
|
||
|
||
return lc;
|
||
}
|
||
|
||
void
|
||
image_stop_load (gpointer context)
|
||
{
|
||
LoadContext* lc = context;
|
||
|
||
g_return_if_fail(lc != NULL);
|
||
|
||
gdk_pixbuf_unref(lc->pixbuf);
|
||
|
||
png_destroy_read_struct(&lc->png_read_ptr, NULL, NULL);
|
||
g_free(lc);
|
||
}
|
||
|
||
gboolean
|
||
image_load_increment(gpointer context, guchar *buf, guint size)
|
||
{
|
||
LoadContext* lc = context;
|
||
|
||
g_return_val_if_fail(lc != NULL, FALSE);
|
||
|
||
/* Invokes our callbacks as needed */
|
||
png_process_data(lc->png_read_ptr, lc->png_info_ptr, buf, size);
|
||
|
||
if (lc->fatal_error_occurred)
|
||
return FALSE;
|
||
else
|
||
return TRUE;
|
||
}
|
||
|
||
/* Called at the start of the progressive load, once we have image info */
|
||
static void
|
||
png_info_callback (png_structp png_read_ptr,
|
||
png_infop png_info_ptr)
|
||
{
|
||
LoadContext* lc;
|
||
png_uint_32 width, height;
|
||
int color_type;
|
||
gboolean have_alpha = FALSE;
|
||
gboolean failed = FALSE;
|
||
|
||
lc = png_get_progressive_ptr(png_read_ptr);
|
||
|
||
if (lc->fatal_error_occurred)
|
||
return;
|
||
|
||
|
||
setup_png_transformations(lc->png_read_ptr,
|
||
lc->png_info_ptr,
|
||
&failed,
|
||
&width, &height, &color_type);
|
||
|
||
if (failed) {
|
||
lc->fatal_error_occurred = TRUE;
|
||
return;
|
||
}
|
||
|
||
/* If we have alpha, set a flag */
|
||
if (color_type & PNG_COLOR_MASK_ALPHA)
|
||
have_alpha = TRUE;
|
||
|
||
lc->pixbuf = gdk_pixbuf_new(ART_PIX_RGB, have_alpha, 8, width, height);
|
||
|
||
if (lc->pixbuf == NULL) {
|
||
/* Failed to allocate memory */
|
||
lc->fatal_error_occurred = TRUE;
|
||
return;
|
||
}
|
||
|
||
/* Notify the client that we are ready to go */
|
||
|
||
if (lc->notify_func)
|
||
(* lc->notify_func) (lc->pixbuf, lc->notify_user_data);
|
||
|
||
return;
|
||
}
|
||
|
||
/* Called for each row; note that you will get duplicate row numbers
|
||
for interlaced PNGs */
|
||
static void
|
||
png_row_callback (png_structp png_read_ptr,
|
||
png_bytep new_row,
|
||
png_uint_32 row_num,
|
||
int pass_num)
|
||
{
|
||
LoadContext* lc;
|
||
guchar* old_row = NULL;
|
||
|
||
lc = png_get_progressive_ptr(png_read_ptr);
|
||
|
||
if (lc->fatal_error_occurred)
|
||
return;
|
||
|
||
old_row = lc->pixbuf->art_pixbuf->pixels + (row_num * lc->pixbuf->art_pixbuf->rowstride);
|
||
|
||
png_progressive_combine_row(lc->png_read_ptr, old_row, new_row);
|
||
}
|
||
|
||
/* Called after reading the entire image */
|
||
static void
|
||
png_end_callback (png_structp png_read_ptr,
|
||
png_infop png_info_ptr)
|
||
{
|
||
LoadContext* lc;
|
||
|
||
lc = png_get_progressive_ptr(png_read_ptr);
|
||
|
||
if (lc->fatal_error_occurred)
|
||
return;
|
||
|
||
/* Doesn't do anything for now */
|
||
}
|
||
|
||
|
||
static void
|
||
png_error_callback(png_structp png_read_ptr,
|
||
png_const_charp error_msg)
|
||
{
|
||
LoadContext* lc;
|
||
|
||
lc = png_get_error_ptr(png_read_ptr);
|
||
|
||
lc->fatal_error_occurred = TRUE;
|
||
|
||
fprintf(stderr, "Fatal error loading PNG: %s\n", error_msg);
|
||
}
|
||
|
||
static void
|
||
png_warning_callback(png_structp png_read_ptr,
|
||
png_const_charp warning_msg)
|
||
{
|
||
LoadContext* lc;
|
||
|
||
lc = png_get_error_ptr(png_read_ptr);
|
||
|
||
fprintf(stderr, "Warning loading PNG: %s\n", warning_msg);
|
||
}
|
||
|