--- /dev/null
+/*M///////////////////////////////////////////////////////////////////////////////////////
+//
+// IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING.
+//
+// By downloading, copying, installing or using the software you agree to this license.
+// If you do not agree to this license, do not download, install,
+// copy or use the software.
+//
+//
+// License Agreement
+// For Open Source Computer Vision Library
+//
+// Copyright (C) 2000-2008, Intel Corporation, all rights reserved.
+// Copyright (C) 2009, Willow Garage Inc., all rights reserved.
+// Third party copyrights are property of their respective owners.
+//
+// Redistribution and use in source and binary forms, with or without modification,
+// are permitted provided that the following conditions are met:
+//
+// * Redistribution's of source code must retain the above copyright notice,
+// this list of conditions and the following disclaimer.
+//
+// * Redistribution's in binary form must reproduce the above copyright notice,
+// this list of conditions and the following disclaimer in the documentation
+// and/or other materials provided with the distribution.
+//
+// * The name of the copyright holders may not be used to endorse or promote products
+// derived from this software without specific prior written permission.
+//
+// This software is provided by the copyright holders and contributors "as is" and
+// any express or implied warranties, including, but not limited to, the implied
+// warranties of merchantability and fitness for a particular purpose are disclaimed.
+// In no event shall the Intel Corporation or contributors be liable for any direct,
+// indirect, incidental, special, exemplary, or consequential damages
+// (including, but not limited to, procurement of substitute goods or services;
+// loss of use, data, or profits; or business interruption) however caused
+// and on any theory of liability, whether in contract, strict liability,
+// or tort (including negligence or otherwise) arising in any way out of
+// the use of this software, even if advised of the possibility of such damage.
+//
+//M*/
+
+#include "_highgui.h"
+
+#ifdef HAVE_PNG
+
+/****************************************************************************************\
+ This part of the file implements PNG codec on base of libpng library,
+ in particular, this code is based on example.c from libpng
+ (see otherlibs/_graphics/readme.txt for copyright notice)
+ and png2bmp sample from libpng distribution (Copyright (C) 1999-2001 MIYASAKA Masaru)
+\****************************************************************************************/
+
+#ifdef HAVE_LIBPNG_PNG_H
+#include <libpng/png.h>
+#else
+#include <png.h>
+#endif
+#include "grfmt_png.h"
+
+namespace cv
+{
+
+/////////////////////// PngDecoder ///////////////////
+
+PngDecoder::PngDecoder()
+{
+ m_signature = "\x89\x50\x4e\x47\xd\xa\x1a\xa";
+ m_color_type = 0;
+ m_png_ptr = 0;
+ m_info_ptr = m_end_info = 0;
+ m_f = 0;
+ m_buf_supported = true;
+ m_buf_pos = 0;
+}
+
+
+PngDecoder::~PngDecoder()
+{
+ close();
+}
+
+ImageDecoder PngDecoder::newDecoder() const
+{
+ return new PngDecoder;
+}
+
+void PngDecoder::close()
+{
+ if( m_f )
+ {
+ fclose( m_f );
+ m_f = 0;
+ }
+
+ if( m_png_ptr )
+ {
+ png_structp png_ptr = (png_structp)m_png_ptr;
+ png_infop info_ptr = (png_infop)m_info_ptr;
+ png_infop end_info = (png_infop)m_end_info;
+ png_destroy_read_struct( &png_ptr, &info_ptr, &end_info );
+ m_png_ptr = m_info_ptr = m_end_info = 0;
+ }
+}
+
+
+void PngDecoder::readDataFromBuf( void* _png_ptr, uchar* dst, size_t size )
+{
+ png_structp png_ptr = (png_structp)_png_ptr;
+ PngDecoder* decoder = (PngDecoder*)(png_ptr->io_ptr);
+ CV_Assert( decoder );
+ const Mat& buf = decoder->m_buf;
+ if( decoder->m_buf_pos + size > buf.cols*buf.rows*buf.elemSize() )
+ {
+ png_error(png_ptr, "PNG input buffer is incomplete");
+ return;
+ }
+ memcpy( dst, &decoder->m_buf.data[decoder->m_buf_pos], size );
+ decoder->m_buf_pos += size;
+}
+
+bool PngDecoder::readHeader()
+{
+ bool result = false;
+ close();
+
+ png_structp png_ptr = png_create_read_struct( PNG_LIBPNG_VER_STRING, 0, 0, 0 );
+
+ if( png_ptr )
+ {
+ png_infop info_ptr = png_create_info_struct( png_ptr );
+ png_infop end_info = png_create_info_struct( png_ptr );
+
+ m_png_ptr = png_ptr;
+ m_info_ptr = info_ptr;
+ m_end_info = end_info;
+ m_buf_pos = 0;
+
+ if( info_ptr && end_info )
+ {
+ if( setjmp( png_ptr->jmpbuf ) == 0 )
+ {
+ if( !m_buf.empty() )
+ png_set_read_fn(png_ptr, this, (png_rw_ptr)readDataFromBuf );
+ else
+ {
+ m_f = fopen( m_filename.c_str(), "rb" );
+ if( m_f )
+ png_init_io( png_ptr, m_f );
+ }
+
+ if( !m_buf.empty() || m_f )
+ {
+ png_uint_32 width, height;
+ int bit_depth, color_type;
+
+ png_read_info( png_ptr, info_ptr );
+
+ png_get_IHDR( png_ptr, info_ptr, &width, &height,
+ &bit_depth, &color_type, 0, 0, 0 );
+
+ m_width = (int)width;
+ m_height = (int)height;
+ m_color_type = color_type;
+ m_bit_depth = bit_depth;
+
+ if( bit_depth <= 8 || bit_depth == 16 )
+ {
+ m_type = color_type == PNG_COLOR_TYPE_RGB ||
+ color_type == PNG_COLOR_TYPE_RGB_ALPHA ||
+ color_type == PNG_COLOR_TYPE_PALETTE ? CV_8UC3 : CV_8UC1;
+ if( bit_depth == 16 )
+ m_type = CV_MAKETYPE(CV_16U, CV_MAT_CN(m_type));
+ result = true;
+ }
+ }
+ }
+ }
+ }
+
+ if( !result )
+ close();
+
+ return result;
+}
+
+
+bool PngDecoder::readData( Mat& img )
+{
+ bool result = false;
+ AutoBuffer<uchar*> _buffer(m_height);
+ uchar** buffer = _buffer;
+ int color = img.channels() > 1;
+ uchar* data = img.data;
+ int step = img.step;
+
+ if( m_png_ptr && m_info_ptr && m_end_info && m_width && m_height )
+ {
+ png_structp png_ptr = (png_structp)m_png_ptr;
+ png_infop info_ptr = (png_infop)m_info_ptr;
+ png_infop end_info = (png_infop)m_end_info;
+
+ if( setjmp(png_ptr->jmpbuf) == 0 )
+ {
+ int y;
+
+ if( img.depth() == CV_8U && m_bit_depth == 16 )
+ png_set_strip_16( png_ptr );
+ else if( !isBigEndian() )
+ png_set_swap( png_ptr );
+
+ /* observation: png_read_image() writes 400 bytes beyond
+ * end of data when reading a 400x118 color png
+ * "mpplus_sand.png". OpenCV crashes even with demo
+ * programs. Looking at the loaded image I'd say we get 4
+ * bytes per pixel instead of 3 bytes per pixel. Test
+ * indicate that it is a good idea to always ask for
+ * stripping alpha.. 18.11.2004 Axel Walthelm
+ */
+ png_set_strip_alpha( png_ptr );
+
+ if( m_color_type == PNG_COLOR_TYPE_PALETTE )
+ png_set_palette_to_rgb( png_ptr );
+
+ if( m_color_type == PNG_COLOR_TYPE_GRAY && m_bit_depth < 8 )
+ png_set_gray_1_2_4_to_8( png_ptr );
+
+ if( CV_MAT_CN(m_type) > 1 && color )
+ png_set_bgr( png_ptr ); // convert RGB to BGR
+ else if( color )
+ png_set_gray_to_rgb( png_ptr ); // Gray->RGB
+ else
+ png_set_rgb_to_gray( png_ptr, 1, -1, -1 ); // RGB->Gray
+
+ png_read_update_info( png_ptr, info_ptr );
+
+ for( y = 0; y < m_height; y++ )
+ buffer[y] = data + y*step;
+
+ png_read_image( png_ptr, buffer );
+ png_read_end( png_ptr, end_info );
+
+ result = true;
+ }
+ }
+
+ close();
+ return result;
+}
+
+
+/////////////////////// PngEncoder ///////////////////
+
+
+PngEncoder::PngEncoder()
+{
+ m_description = "Portable Network Graphics files (*.png)";
+ m_buf_supported = true;
+}
+
+
+PngEncoder::~PngEncoder()
+{
+}
+
+
+bool PngEncoder::isFormatSupported( int depth ) const
+{
+ return depth == CV_8U || depth == CV_16U;
+}
+
+ImageEncoder PngEncoder::newEncoder() const
+{
+ return new PngEncoder;
+}
+
+
+void PngEncoder::writeDataToBuf(void* _png_ptr, uchar* src, size_t size)
+{
+ if( size == 0 )
+ return;
+ png_structp png_ptr = (png_structp)_png_ptr;
+ PngEncoder* encoder = (PngEncoder*)(png_ptr->io_ptr);
+ CV_Assert( encoder && encoder->m_buf );
+ size_t cursz = encoder->m_buf->size();
+ encoder->m_buf->resize(cursz + size);
+ memcpy( &(*encoder->m_buf)[cursz], src, size );
+}
+
+
+void PngEncoder::flushBuf(void*)
+{
+}
+
+bool PngEncoder::write( const Mat& img, const vector<int>& params )
+{
+ int compression_level = 0;
+
+ for( size_t i = 0; i < params.size(); i += 2 )
+ {
+ if( params[i] == CV_IMWRITE_PNG_COMPRESSION )
+ {
+ compression_level = params[i+1];
+ compression_level = MIN(MAX(compression_level, 0), MAX_MEM_LEVEL);
+ }
+ }
+
+ png_structp png_ptr = png_create_write_struct( PNG_LIBPNG_VER_STRING, 0, 0, 0 );
+ png_infop info_ptr = 0;
+ FILE* f = 0;
+ int y, width = img.cols, height = img.rows;
+ int depth = img.depth(), channels = img.channels();
+ bool result = false;
+ AutoBuffer<uchar*> buffer;
+
+ if( depth != CV_8U && depth != CV_16U )
+ return false;
+
+ if( png_ptr )
+ {
+ info_ptr = png_create_info_struct( png_ptr );
+
+ if( info_ptr )
+ {
+ if( setjmp( png_ptr->jmpbuf ) == 0 )
+ {
+ if( m_buf )
+ {
+ png_set_write_fn(png_ptr, this,
+ (png_rw_ptr)writeDataToBuf, (png_flush_ptr)flushBuf);
+ }
+ else
+ {
+ f = fopen( m_filename.c_str(), "wb" );
+ if( f )
+ png_init_io( png_ptr, f );
+ }
+
+ if( m_buf || f )
+ {
+ if( compression_level > 0 )
+ {
+ png_set_compression_mem_level( png_ptr, compression_level );
+ }
+ else
+ {
+ // tune parameters for speed
+ // (see http://wiki.linuxquestions.org/wiki/Libpng)
+ png_set_filter(png_ptr, PNG_FILTER_TYPE_BASE, PNG_FILTER_SUB);
+ png_set_compression_level(png_ptr, Z_BEST_SPEED);
+ }
+ png_set_compression_strategy(png_ptr, Z_HUFFMAN_ONLY);
+
+ png_set_IHDR( png_ptr, info_ptr, width, height, depth == CV_8U ? 8 : 16,
+ channels == 1 ? PNG_COLOR_TYPE_GRAY :
+ channels == 3 ? PNG_COLOR_TYPE_RGB : PNG_COLOR_TYPE_RGBA,
+ PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT,
+ PNG_FILTER_TYPE_DEFAULT );
+
+ png_write_info( png_ptr, info_ptr );
+
+ png_set_bgr( png_ptr );
+ if( !isBigEndian() )
+ png_set_swap( png_ptr );
+
+ buffer.allocate(height);
+ for( y = 0; y < height; y++ )
+ buffer[y] = img.data + y*img.step;
+
+ png_write_image( png_ptr, buffer );
+ png_write_end( png_ptr, info_ptr );
+
+ result = true;
+ }
+ }
+ }
+ }
+
+ png_destroy_write_struct( &png_ptr, &info_ptr );
+ if(f) fclose( f );
+
+ return result;
+}
+
+}
+
+#endif
+
+/* End of file. */
projects / opencv / blobdiff