-
-//-----------------------------------------------------------------------------
-// wxPNGHandler
-//-----------------------------------------------------------------------------
-
-#ifdef wxUSE_LIBPNG
-
-#if !USE_SHARED_LIBRARIES
-IMPLEMENT_DYNAMIC_CLASS(wxPNGHandler,wxImageHandler)
-#endif
-
-
-static void _PNG_stream_reader( png_structp png_ptr, png_bytep data, png_size_t length )
-{
- ((wxInputStream*) png_get_io_ptr( png_ptr )) -> Read(data, length);
-}
-
-static void _PNG_stream_writer( png_structp png_ptr, png_bytep data, png_size_t length )
-{
- ((wxOutputStream*) png_get_io_ptr( png_ptr )) -> Write(data, length);
-}
-
-bool wxPNGHandler::LoadFile( wxImage *image, wxInputStream& stream )
-{
- // VZ: as this function uses setjmp() the only fool proof error handling
- // method is to use goto (setjmp is not really C++ dtors friendly...)
-
- unsigned char **lines = (unsigned char **) NULL;
- unsigned int i;
- png_infop info_ptr = (png_infop) NULL;
-
- image->Destroy();
-
- png_structp png_ptr = png_create_read_struct( PNG_LIBPNG_VER_STRING,
- (voidp) NULL,
- (png_error_ptr) NULL,
- (png_error_ptr) NULL );
- if (!png_ptr)
- goto error;
-
- info_ptr = png_create_info_struct( png_ptr );
- if (!info_ptr)
- goto error;
-
- if (setjmp(png_ptr->jmpbuf))
- goto error;
-
- if (info_ptr->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
- goto error;
-
- png_set_read_fn( png_ptr, &stream, _PNG_stream_reader);
-
- png_uint_32 width,height;
- int bit_depth,color_type,interlace_type;
-
- png_read_info( png_ptr, info_ptr );
- png_get_IHDR( png_ptr, info_ptr, &width, &height, &bit_depth, &color_type, &interlace_type, (int*) NULL, (int*) NULL );
-
- if (color_type == PNG_COLOR_TYPE_PALETTE)
- png_set_expand( png_ptr );
-
- png_set_strip_16( png_ptr );
- png_set_packing( png_ptr );
- if (png_get_valid( png_ptr, info_ptr, PNG_INFO_tRNS))
- png_set_expand( png_ptr );
- png_set_filler( png_ptr, 0xff, PNG_FILLER_AFTER );
-
- image->Create( width, height );
-
- if (!image->Ok())
- goto error;
-
- lines = (unsigned char **)malloc( height * sizeof(unsigned char *) );
- if (lines == NULL)
- goto error;
-
- for (i = 0; i < height; i++)
- {
- if ((lines[i] = (unsigned char *)malloc(width * (sizeof(unsigned char) * 4))) == NULL)
- {
- for ( unsigned int n = 0; n < i; n++ )
- free( lines[n] );
- goto error;
- }
- }
-
- // loaded successfully!
- {
- int transp = 0;
- png_read_image( png_ptr, lines );
- png_destroy_read_struct( &png_ptr, &info_ptr, (png_infopp) NULL );
- unsigned char *ptr = image->GetData();
- if ((color_type == PNG_COLOR_TYPE_GRAY) ||
- (color_type == PNG_COLOR_TYPE_GRAY_ALPHA))
- {
- for (unsigned int y = 0; y < height; y++)
- {
- unsigned char *ptr2 = lines[y];
- for (unsigned int x = 0; x < width; x++)
- {
- unsigned char r = *ptr2++;
- unsigned char a = *ptr2++;
- if (a < 128)
- {
- *ptr++ = 255;
- *ptr++ = 0;
- *ptr++ = 255;
- transp = 1;
- }
- else
- {
- *ptr++ = r;
- *ptr++ = r;
- *ptr++ = r;
- }
- }
- }
- }
- else
- {
- for (unsigned int y = 0; y < height; y++)
- {
- unsigned char *ptr2 = lines[y];
- for (unsigned int x = 0; x < width; x++)
- {
- unsigned char r = *ptr2++;
- unsigned char g = *ptr2++;
- unsigned char b = *ptr2++;
- unsigned char a = *ptr2++;
- if (a < 128)
- {
- *ptr++ = 255;
- *ptr++ = 0;
- *ptr++ = 255;
- transp = 1;
- }
- else
- {
- if ((r == 255) && (g == 0) && (b == 255)) r = 254;
- *ptr++ = r;
- *ptr++ = g;
- *ptr++ = b;
- }
- }
- }
- }
-
- for ( unsigned int j = 0; j < height; j++ )
- free( lines[j] );
- free( lines );
-
- if (transp)
- {
- image->SetMaskColour( 255, 0, 255 );
- }
- else
- {
- image->SetMask( FALSE );
- }
- }
-
- return TRUE;
-
-error:
- wxLogError(_("Couldn't load a PNG image - probably file is corrupted."));
-
- if ( image->Ok() )
- {
- image->Destroy();
- }
-
- if ( lines )
- {
- free( lines );
- }
-
- if ( png_ptr )
- {
- if ( info_ptr )
- {
- png_destroy_read_struct( &png_ptr, &info_ptr, (png_infopp) NULL );
- free(info_ptr);
- }
- else
- png_destroy_read_struct( &png_ptr, (png_infopp) NULL, (png_infopp) NULL );
- }
- return FALSE;
-}
-
-
-bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream )
-{
- {
- png_structp png_ptr = png_create_write_struct( PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
- if (!png_ptr)
- {
- return FALSE;
- }
-
- png_infop info_ptr = png_create_info_struct(png_ptr);
- if (info_ptr == NULL)
- {
- png_destroy_write_struct( &png_ptr, (png_infopp)NULL );
- return FALSE;
- }
-
- if (setjmp(png_ptr->jmpbuf))
- {
- png_destroy_write_struct( &png_ptr, (png_infopp)NULL );
- return FALSE;
- }
-
- png_set_write_fn( png_ptr, &stream, _PNG_stream_writer, NULL);
-
- png_set_IHDR( png_ptr, info_ptr, image->GetWidth(), image->GetHeight(), 8,
- PNG_COLOR_TYPE_RGB_ALPHA, PNG_INTERLACE_NONE,
- PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
-
- png_color_8 sig_bit;
- sig_bit.red = 8;
- sig_bit.green = 8;
- sig_bit.blue = 8;
- sig_bit.alpha = 8;
- png_set_sBIT( png_ptr, info_ptr, &sig_bit );
- png_write_info( png_ptr, info_ptr );
- png_set_shift( png_ptr, &sig_bit );
- png_set_packing( png_ptr );
-
- unsigned char *data = (unsigned char *)malloc( image->GetWidth()*4 );
- if (!data)
- {
- png_destroy_write_struct( &png_ptr, (png_infopp)NULL );
- return FALSE;
- }
-
- for (int y = 0; y < image->GetHeight(); y++)
- {
- unsigned char *ptr = image->GetData() + (y * image->GetWidth() * 3);
- for (int x = 0; x < image->GetWidth(); x++)
- {
- data[(x << 2) + 0] = *ptr++;
- data[(x << 2) + 1] = *ptr++;
- data[(x << 2) + 2] = *ptr++;
- if ((data[(x << 2) + 0] == image->GetMaskRed()) &&
- (data[(x << 2) + 1] == image->GetMaskGreen()) &&
- (data[(x << 2) + 2] == image->GetMaskBlue()))
- {
- data[(x << 2) + 3] = 0;
- }
- else
- {
- data[(x << 2) + 3] = 255;
- }
- }
- png_bytep row_ptr = data;
- png_write_rows( png_ptr, &row_ptr, 1 );
- }
-
- free(data);
- png_write_end( png_ptr, info_ptr );
- png_destroy_write_struct( &png_ptr, (png_infopp)&info_ptr );
- }
- return TRUE;
-}
-
-#endif
-
- // wxUSE_LIBPNG