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/*
* $Id$
*
* (C) 2003-2006 Gabest
* (C) 2006-2010 see AUTHORS
*
* This file is part of mplayerc.
*
* Mplayerc is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
*
* Mplayerc 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
#include <stdio.h>
#include <malloc.h>
#include "libpng.h"
#include "../../thirdparty/libpng/png.h"
static void read_data_fn(png_structp png_ptr, png_bytep data, png_size_t length)
{
struct png_t* png = (struct png_t*)png_get_progressive_ptr(png_ptr);
if(png->pos + length > png->size) png_error(png_ptr, "Read Error");
memcpy(data, &png->data[png->pos], length);
png->pos += length;
}
unsigned char* DecompressPNG(struct png_t* png, int* w, int* h)
{
png_structp png_ptr;
png_infop info_ptr;
png_infop end_info;
unsigned char* pic;
unsigned char* row;
unsigned int x, y, c;
if(png_sig_cmp(png->data, 0, 8) != 0)
return NULL;
png->pos = 8;
png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
// (png_voidp)user_error_ptr, user_error_fn, user_warning_fn);
if(!png_ptr)
return NULL;
png_set_read_fn(png_ptr, (png_voidp)png, read_data_fn);
info_ptr = png_create_info_struct(png_ptr);
if(!info_ptr)
{
png_destroy_read_struct(&png_ptr, (png_infopp)NULL, (png_infopp)NULL);
return NULL;
}
end_info = png_create_info_struct(png_ptr);
if(!end_info)
{
png_destroy_read_struct(&png_ptr, &info_ptr, (png_infopp)NULL);
return NULL;
}
if(setjmp(png_jmpbuf(png_ptr)))
{
png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);
return NULL;
}
png_set_sig_bytes(png_ptr, 8);
png_read_png(
png_ptr, info_ptr,
PNG_TRANSFORM_STRIP_16 |
PNG_TRANSFORM_STRIP_ALPHA |
PNG_TRANSFORM_PACKING |
PNG_TRANSFORM_EXPAND |
PNG_TRANSFORM_BGR,
NULL);
if(png_get_channels(png_ptr, info_ptr) != 3)
{
png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);
return NULL;
}
pic = calloc(info_ptr->width * info_ptr->height, 4);
*w = info_ptr->width;
*h = info_ptr->height;
for(y = 0; y < info_ptr->height; y++)
{
row = &pic[y * info_ptr->width * 4];
for(x = 0; x < info_ptr->width*3; row += 4)
{
for(c = 0; c < 3; c++)
{
row[c] = info_ptr->row_pointers[y][x++];
}
}
}
png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);
return pic;
}
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