function Start(URL, WIDTH, HEIGHT, ALT) {
var windowprops = "width=" + WIDTH + ",height=" + (HEIGHT+30);
var text = "'" + ALT + "'![" + ALT + "](" + URL + ")
";
preview = top.window.open("", "preview", windowprops);
preview.top.document.open();
preview.top.document.write(text);
preview.document.close();
}