function validateform() {
	var filename = document.form.file.value.replace(/^\s+|\s+$/g,"");
	var size = document.form.size.value.replace(/^\s+|\s+$/g,"");
	if(!filename ||!size) {
		alert("Make sure you filled both fields");
		return false;
	}
	else if(!isint(size)) {
		alert("Please provide an integer for the size of the drop shadow");
		return false;
	}
	else if(size<3 || size>12) {
		alert("Please choose a size between 3 and 12 pixels");
		return false;
	}
}
function isint(num) {
	for (i = 0; i < num.length; i++){
		var c = num.charAt(i);	
		if (!((c >= "0") && (c <= "9")))
			return false;
	}
	return true;
}