function disableurlfield(el){
if (el.value!="") el.form.url.value=""
el.style.color='black'
if (document.getElementById && document.all){
document.previewimg.src = 'file:///'+el.form.userfile.value;
previewuploaded(el)
}
}

function previewuploaded(el){
var imgtest=/(.gif)|(.jpg)|(.png)/gi
if (imgtest.test(el.value)){
document.getElementById("previewarea").innerHTML='<b>Image Selected (may be partially hidden):</b><p><img src="'+'file:///'+el.form.userfile.value+'"></p>'
document.getElementById("previewarea").style.display="block"
}
}

function checktypesize(el){
if (el.form.url.value!="")
return IsValidImageType(el.form.url.value)
else
return IsValidImageType(el.form.userfile.value)
}


function ShowHideDIV(el) {
		if (document.getElementById && document.all) {
		document.previewimg.src = 'file:///'+el.value; 
			if (el.value == "") {
				document.getElementById("previewdiv").style.display = "none";
			} else {
				document.getElementById("previewdiv").style.display = "block";
			}
		}
		return true;
	}


	function IsValidImageSize() {
		if ((document.previewimg.fileSize * 0) != 0) {
			// most browsers other than IE don't return a value for filesize
			// so just let them through and let PHP catch it on the other side
			return true;
		}
		if (navigator.userAgent.indexOf("Mac")!=-1)
		return true;
		if (document.previewimg.fileSize == -1) {
			// file types that the browser doesn't understand won't create a
			// valid image and therefore probably return a "-1" filesize
			return true;
		}

		if ((document.previewimg.fileSize > 0) && (document.previewimg.fileSize < rawmaxsize)) {
			return true;
		}
		alert('This image is too large! \n\nThis max file size allowed is: '+humanmaxsize);
		return false;


	}
	function IsValidImageType(filename) {
		if (filename == "") {
			alert('Please specify an image to optimize');
			return false;
		}
		var reg = /(gif|png|jpe?g?)$/i;
		if (!reg.test(filename)) {
			alert('Only JPEG, PNG, GIF, and Animated GIFs allowed');
			return false;
		}
		return IsValidImageSize();
	}