function ImagePreview(image_url, size1, size2) {

if (size1 > 500) {
	size2 = (500 * size2) / size1;
	size1 = 500;
}
if (size2 > 600) {
	size1 = (600 * size1) / size2;
	size2 = 600;
}

size1=size1+50;
size2=size2+75;

F = window.open(image_url + "/ImagePopup","Popup","resizable=1,status=0,scrollbars=1,width=" + size1 +",height="+ size2 );
F.focus();
}

function AttachmentPreview(preview_url, size1, size2) {
if (size1 > 500) {
	size2 = (500 * size2) / size1;
	size1 = 500;
}
if (size2 > 600) {
	size1 = (600 * size1) / size2;
	size2 = 600;
}


F = window.open(preview_url,"Popup","resizable=1,status=0,scrollbars=1,width=" + size1 +",height="+ size2 );
F.focus();
}