if (jQuery && weeknum != "" && imgpath != "") {
	var imgnum = ((weeknum + 2) % 4) + 1;
	$.ajax({
		url: imgpath.replace(/<photonum>/,imgnum),
		cache: false,
		success: function(){
			$('#viewbook-banner').attr('src',imgpath.replace(/<photonum>/,imgnum));
		},
		error: function(){
			// image not found, do nothing
		}
	});
}