3 * Purpose: PNG Image Class Loader and Writer
5 /* ==========================================================
6 * CxImagePNG (c) 07/Aug/2001 Davide Pizzolato - www.xdp.it
7 * For conditions of distribution and use, see copyright notice in ximage.h
9 * Special thanks to Troels Knakkergaard for new features, enhancements and bugfixes
11 * original CImagePNG and CImageIterator implementation are:
12 * Copyright: (c) 1995, Alejandro Aguilar Sierra <asierra(at)servidor(dot)unam(dot)mx>
14 * libpng Copyright (c) 1998-2003 Glenn Randers-Pehrson
15 * ==========================================================
17 #if !defined(__ximaPNG_h)
22 #if CXIMAGE_SUPPORT_PNG
25 #include "../png/png.h"
28 class CxImagePNG: public CxImage
31 CxImagePNG(): CxImage(CXIMAGE_FORMAT_PNG) {}
33 // bool Load(const TCHAR * imageFileName){ return CxImage::Load(imageFileName,CXIMAGE_FORMAT_PNG);}
34 // bool Save(const TCHAR * imageFileName){ return CxImage::Save(imageFileName,CXIMAGE_FORMAT_PNG);}
35 bool Decode(CxFile * hFile);
36 bool Decode(FILE *hFile) { CxIOFile file(hFile); return Decode(&file); }
38 #if CXIMAGE_SUPPORT_ENCODE
39 bool Encode(CxFile * hFile);
40 bool Encode(FILE *hFile) { CxIOFile file(hFile); return Encode(&file); }
41 #endif // CXIMAGE_SUPPORT_ENCODE
44 void ima_png_error(png_struct *png_ptr, char *message);
45 void expand2to4bpp(BYTE* prow);
47 static void PNGAPI user_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
49 CxFile* hFile = (CxFile*)png_get_io_ptr(png_ptr);
50 if (hFile == NULL || hFile->Read(data,1,length) != length) png_error(png_ptr, "Read Error");
53 static void PNGAPI user_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
55 CxFile* hFile = (CxFile*)png_get_io_ptr(png_ptr);
56 if (hFile == NULL || hFile->Write(data,1,length) != length) png_error(png_ptr, "Write Error");
59 static void PNGAPI user_flush_data(png_structp png_ptr)
61 CxFile* hFile = (CxFile*)png_get_io_ptr(png_ptr);
62 if (hFile == NULL || !hFile->Flush()) png_error(png_ptr, "Flush Error");
65 static void PNGAPI user_error_fn(png_structp png_ptr,png_const_charp error_msg)
67 strncpy((char*)png_ptr->error_ptr,error_msg,255);
68 longjmp(png_ptr->jmpbuf, 1);