	// create the offscreen
	err = QTNewGWorld( &sourceGWorld,			// returned GWorld
					   k32ARGBPixelFormat,		// pixel format 
					   &naturalBounds,			// bounds 
					   NULL,					// cTable 	
					   NULL, 					// GDevice
					   kICMTempThenAppMemory );	// flags
	LockPixels( GetGWorldPixMap( sourceGWorld ) );
	
	// set the graphics port for drawing
	err = GraphicsImportSetGWorld( importer, sourceGWorld, NULL );
	
	// draw the image to the offscreen
	err = GraphicsImportDraw( importer );

	// blit the offscreen to the window
	CopyBits(GetPortBitMapForCopyBits(sourceGWorld),
			 GetPortBitMapForCopyBits(GetWindowPort(window)),
			 &naturalBounds,
			 &naturalBounds,
			 ditherCopy,
			 NULL);