Bug 53274 [SWT Examples] Image Analyzer crashed when tried to save images as PNGs and ICOs
examples/org.eclipse.swt.examples/src/org/eclipse/swt/examples/imageanalyzer/ImageAnalyzer.java
item.setText("K");
		item.addSelectionListener(new SelectionAdapter() {
			public void widgetSelected(SelectionEvent event) {
				menuComposeAlpha(ALPHA_CONSTANT);
			}
		});
		
		item = new MenuItem(alphaMenu, SWT.PUSH);
		item.setText("(K + x) % 256");
		item.addSelectionListener(new SelectionAdapter() {
			public void widgetSelected(SelectionEvent event) {
				menuComposeAlpha(ALPHA_X);
			}
		});
		
		item = new MenuItem(alphaMenu, SWT.PUSH);
		item.setText("(K + y) % 256");
		item.addSelectionListener(new SelectionAdapter() {
			public void widgetSelected(SelectionEvent event) {
				menuComposeAlpha(ALPHA_Y);
			}
		});
	}
	void menuComposeAlpha(int alpha_op) {
		if (image == null) return;
		animate = false; 
		Cursor waitCursor = new Cursor(display, SWT.CURSOR_WAIT);
		shell.setCursor(waitCursor);
		imageCanvas.setCursor(waitCursor);
		try {