source: liacs/MIR2010/SourceCode/cximage/ximapng.h@ 104

/*
 * File:        ximapng.h
 * Purpose:     PNG Image Class Loader and Writer
 */
/* ==========================================================
 * CxImagePNG (c) 07/Aug/2001 Davide Pizzolato - www.xdp.it
 * For conditions of distribution and use, see copyright notice in ximage.h
 *
 * Special thanks to Troels Knakkergaard for new features, enhancements and bugfixes
 *
 * original CImagePNG  and CImageIterator implementation are:
 * Copyright:   (c) 1995, Alejandro Aguilar Sierra <asierra(at)servidor(dot)unam(dot)mx>
 *
 * libpng Copyright (c) 1998-2003 Glenn Randers-Pehrson
 * ==========================================================
 */
#if !defined(__ximaPNG_h)
#define __ximaPNG_h

#include "ximage.h"

#if CXIMAGE_SUPPORT_PNG

extern "C" {
#include "png/png.h"
}

class CxImagePNG: public CxImage
{
public:
        CxImagePNG(): CxImage(CXIMAGE_FORMAT_PNG) {}

//      bool Load(const TCHAR * imageFileName){ return CxImage::Load(imageFileName,CXIMAGE_FORMAT_PNG);}
//      bool Save(const TCHAR * imageFileName){ return CxImage::Save(imageFileName,CXIMAGE_FORMAT_PNG);}
        bool Decode(CxFile * hFile);
        bool Decode(FILE *hFile) { CxIOFile file(hFile); return Decode(&file); }

#if CXIMAGE_SUPPORT_ENCODE
        bool Encode(CxFile * hFile);
        bool Encode(FILE *hFile) { CxIOFile file(hFile); return Encode(&file); }
#endif // CXIMAGE_SUPPORT_ENCODE

protected:
        void ima_png_error(png_struct *png_ptr, char *message);
        void expand2to4bpp(BYTE* prow);

        static void PNGAPI user_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
        {
                CxFile* hFile = (CxFile*)png_get_io_ptr(png_ptr);
                if (hFile == NULL || hFile->Read(data,1,length) != length) png_error(png_ptr, "Read Error");
        }

        static void PNGAPI user_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
        {
                CxFile* hFile = (CxFile*)png_get_io_ptr(png_ptr);
                if (hFile == NULL || hFile->Write(data,1,length) != length) png_error(png_ptr, "Write Error");
        }

        static void PNGAPI user_flush_data(png_structp png_ptr)
        {
                CxFile* hFile = (CxFile*)png_get_io_ptr(png_ptr);
                if (hFile == NULL || !hFile->Flush()) png_error(png_ptr, "Flush Error");
        }

    static void PNGAPI user_error_fn(png_structp png_ptr,png_const_charp error_msg)
        {
                strncpy((char*)png_ptr->error_ptr,error_msg,255);
                longjmp(png_ptr->jmpbuf, 1);
        }
};

#endif

#endif