function openWindow(url,w,h){
			
			var winl = (screen.width-w)/2;
			var wint = (screen.height-h)/2;
			if (winl < 0) winl = 0;
			if (wint < 0) wint = 0;
		
			var windowProps = "toolbar=no,scrollbars=no,resizable=no,status=no,menubar=no,height=" + h + ", width = " + w + ", left = " + winl + ", top = " + wint;
		
			window.open(url, "Image", windowProps)
}