1/*M/////////////////////////////////////////////////////////////////////////////////////// 2// 3// IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING. 4// 5// By downloading, copying, installing or using the software you agree to this license. 6// If you do not agree to this license, do not download, install, 7// copy or use the software. 8// 9// 10// Intel License Agreement 11// For Open Source Computer Vision Library 12// 13// Copyright (C) 2000, Intel Corporation, all rights reserved. 14// Third party copyrights are property of their respective owners. 15// 16// Redistribution and use in source and binary forms, with or without modification, 17// are permitted provided that the following conditions are met: 18// 19// * Redistribution's of source code must retain the above copyright notice, 20// this list of conditions and the following disclaimer. 21// 22// * Redistribution's in binary form must reproduce the above copyright notice, 23// this list of conditions and the following disclaimer in the documentation 24// and/or other materials provided with the distribution. 25// 26// * The name of Intel Corporation may not be used to endorse or promote products 27// derived from this software without specific prior written permission. 28// 29// This software is provided by the copyright holders and contributors "as is" and 30// any express or implied warranties, including, but not limited to, the implied 31// warranties of merchantability and fitness for a particular purpose are disclaimed. 32// In no event shall the Intel Corporation or contributors be liable for any direct, 33// indirect, incidental, special, exemplary, or consequential damages 34// (including, but not limited to, procurement of substitute goods or services; 35// loss of use, data, or profits; or business interruption) however caused 36// and on any theory of liability, whether in contract, strict liability, 37// or tort (including negligence or otherwise) arising in any way out of 38// the use of this software, even if advised of the possibility of such damage. 39// 40//M*/ 41 42#include "_highgui.h" 43 44#ifdef HAVE_PNG 45 46/****************************************************************************************\ 47 This part of the file implements PNG codec on base of libpng library, 48 in particular, this code is based on example.c from libpng 49 (see otherlibs/_graphics/readme.txt for copyright notice) 50 and png2bmp sample from libpng distribution (Copyright (C) 1999-2001 MIYASAKA Masaru) 51\****************************************************************************************/ 52 53#if defined WIN32 || defined HAVE_PNG_H 54#include <png.h> 55#else 56#include <libpng/png.h> 57#endif 58#include "grfmt_png.h" 59 60// PNG Filter Factory 61GrFmtPng::GrFmtPng() 62{ 63 m_sign_len = 8; 64 m_signature = "\x89\x50\x4e\x47\xd\xa\x1a\xa"; 65 m_description = "Portable Network Graphics files (*.png)"; 66} 67 68 69GrFmtPng::~GrFmtPng() 70{ 71} 72 73 74GrFmtReader* GrFmtPng::NewReader( const char* filename ) 75{ 76 return new GrFmtPngReader( filename ); 77} 78 79 80GrFmtWriter* GrFmtPng::NewWriter( const char* filename ) 81{ 82 return new GrFmtPngWriter( filename ); 83} 84 85 86bool GrFmtPng::CheckSignature( const char* signature ) 87{ 88 return png_check_sig( (uchar*)signature, m_sign_len ) != 0; 89} 90 91/////////////////////// GrFmtPngReader /////////////////// 92 93GrFmtPngReader::GrFmtPngReader( const char* filename ) : GrFmtReader( filename ) 94{ 95 m_color_type = m_bit_depth = 0; 96 m_png_ptr = 0; 97 m_info_ptr = m_end_info = 0; 98 m_f = 0; 99} 100 101 102GrFmtPngReader::~GrFmtPngReader() 103{ 104} 105 106 107void GrFmtPngReader::Close() 108{ 109 if( m_f ) 110 { 111 fclose( m_f ); 112 m_f = 0; 113 } 114 115 if( m_png_ptr ) 116 { 117 png_structp png_ptr = (png_structp)m_png_ptr; 118 png_infop info_ptr = (png_infop)m_info_ptr; 119 png_infop end_info = (png_infop)m_end_info; 120 png_destroy_read_struct( &png_ptr, &info_ptr, &end_info ); 121 m_png_ptr = m_info_ptr = m_end_info = 0; 122 } 123 GrFmtReader::Close(); 124} 125 126 127bool GrFmtPngReader::ReadHeader() 128{ 129 bool result = false; 130 131 Close(); 132 133 png_structp png_ptr = png_create_read_struct( PNG_LIBPNG_VER_STRING, 0, 0, 0 ); 134 135 if( png_ptr ) 136 { 137 png_infop info_ptr = png_create_info_struct( png_ptr ); 138 png_infop end_info = png_create_info_struct( png_ptr ); 139 140 m_png_ptr = png_ptr; 141 m_info_ptr = info_ptr; 142 m_end_info = end_info; 143 144 if( info_ptr && end_info ) 145 { 146 if( setjmp( png_ptr->jmpbuf ) == 0 ) 147 { 148 m_f = fopen( m_filename, "rb" ); 149 if( m_f ) 150 { 151 png_uint_32 width, height; 152 int bit_depth, color_type; 153 154 png_init_io( png_ptr, m_f ); 155 png_read_info( png_ptr, info_ptr ); 156 157 png_get_IHDR( png_ptr, info_ptr, &width, &height, 158 &bit_depth, &color_type, 0, 0, 0 ); 159 160 m_iscolor = color_type == PNG_COLOR_TYPE_RGB || 161 color_type == PNG_COLOR_TYPE_RGB_ALPHA || 162 color_type == PNG_COLOR_TYPE_PALETTE; 163 164 m_width = (int)width; 165 m_height = (int)height; 166 m_color_type = color_type; 167 m_bit_depth = bit_depth; 168 169 result = true; 170 } 171 } 172 } 173 } 174 175 if( !result ) 176 Close(); 177 178 return result; 179} 180 181 182bool GrFmtPngReader::ReadData( uchar* data, int step, int color ) 183{ 184 bool result = false; 185 uchar** buffer = 0; 186 187 color = color > 0 || ( m_iscolor && color < 0 ); 188 189 if( m_png_ptr && m_info_ptr && m_end_info && m_width && m_height ) 190 { 191 png_structp png_ptr = (png_structp)m_png_ptr; 192 png_infop info_ptr = (png_infop)m_info_ptr; 193 png_infop end_info = (png_infop)m_end_info; 194 195 if( setjmp(png_ptr->jmpbuf) == 0 ) 196 { 197 int y; 198 199 if( m_bit_depth > 8 && !m_native_depth ) 200 png_set_strip_16( png_ptr ); 201 else if( !isBigEndian() ) 202 png_set_swap( png_ptr ); 203 204 /* observation: png_read_image() writes 400 bytes beyond 205 * end of data when reading a 400x118 color png 206 * "mpplus_sand.png". OpenCV crashes even with demo 207 * programs. Looking at the loaded image I'd say we get 4 208 * bytes per pixel instead of 3 bytes per pixel. Test 209 * indicate that it is a good idea to always ask for 210 * stripping alpha.. 18.11.2004 Axel Walthelm 211 */ 212 png_set_strip_alpha( png_ptr ); 213 214 if( m_color_type == PNG_COLOR_TYPE_PALETTE ) 215 png_set_palette_to_rgb( png_ptr ); 216 217 if( m_color_type == PNG_COLOR_TYPE_GRAY && m_bit_depth < 8 ) 218 png_set_gray_1_2_4_to_8( png_ptr ); 219 220 if( m_iscolor && color ) 221 png_set_bgr( png_ptr ); // convert RGB to BGR 222 else if( color ) 223 png_set_gray_to_rgb( png_ptr ); // Gray->RGB 224 else 225 png_set_rgb_to_gray( png_ptr, 1, -1, -1 ); // RGB->Gray 226 227 png_read_update_info( png_ptr, info_ptr ); 228 229 buffer = new uchar*[m_height]; 230 231 for( y = 0; y < m_height; y++ ) 232 buffer[y] = data + y*step; 233 234 png_read_image( png_ptr, buffer ); 235 png_read_end( png_ptr, end_info ); 236 237 result = true; 238 } 239 } 240 241 Close(); 242 delete[] buffer; 243 244 return result; 245} 246 247 248/////////////////////// GrFmtPngWriter /////////////////// 249 250 251GrFmtPngWriter::GrFmtPngWriter( const char* filename ) : GrFmtWriter( filename ) 252{ 253} 254 255 256GrFmtPngWriter::~GrFmtPngWriter() 257{ 258} 259 260 261bool GrFmtPngWriter::IsFormatSupported( int depth ) 262{ 263 return depth == IPL_DEPTH_8U || depth == IPL_DEPTH_16U; 264} 265 266bool GrFmtPngWriter::WriteImage( const uchar* data, int step, 267 int width, int height, int depth, int channels ) 268{ 269 png_structp png_ptr = png_create_write_struct( PNG_LIBPNG_VER_STRING, 0, 0, 0 ); 270 png_infop info_ptr = 0; 271 FILE* f = 0; 272 uchar** buffer = 0; 273 int y; 274 bool result = false; 275 276 if( depth != IPL_DEPTH_8U && depth != IPL_DEPTH_16U ) 277 return false; 278 279 if( png_ptr ) 280 { 281 info_ptr = png_create_info_struct( png_ptr ); 282 283 if( info_ptr ) 284 { 285 if( setjmp( png_ptr->jmpbuf ) == 0 ) 286 { 287 f = fopen( m_filename, "wb" ); 288 289 if( f ) 290 { 291 png_init_io( png_ptr, f ); 292 293 png_set_compression_mem_level( png_ptr, MAX_MEM_LEVEL ); 294 295 png_set_IHDR( png_ptr, info_ptr, width, height, depth, 296 channels == 1 ? PNG_COLOR_TYPE_GRAY : 297 channels == 3 ? PNG_COLOR_TYPE_RGB : PNG_COLOR_TYPE_RGBA, 298 PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT, 299 PNG_FILTER_TYPE_DEFAULT ); 300 301 png_write_info( png_ptr, info_ptr ); 302 303 png_set_bgr( png_ptr ); 304 if( !isBigEndian() ) 305 png_set_swap( png_ptr ); 306 307 buffer = new uchar*[height]; 308 for( y = 0; y < height; y++ ) 309 buffer[y] = (uchar*)(data + y*step); 310 311 png_write_image( png_ptr, buffer ); 312 png_write_end( png_ptr, info_ptr ); 313 314 delete[] buffer; 315 316 result = true; 317 } 318 } 319 } 320 } 321 322 png_destroy_write_struct( &png_ptr, &info_ptr ); 323 324 if(f) fclose( f ); 325 326 return result; 327} 328 329#endif 330 331/* End of file. */ 332 333 334