function IsNumeric(sText) {
	var ValidChars = "0123456789";
	var IsNumber=true;
	var Char;
	for (i = 0; i < sText.length && IsNumber == true; i++) { 
		Char = sText.charAt(i); 
		if (ValidChars.indexOf(Char) == -1) {
			IsNumber = false;
		}
	}
	return IsNumber;
}
	   
function form1Submit() {
	//check if form is well filled
	//Minimum of two words required
	var word1 = document.getElementById('word01').value;
	var word2 = document.getElementById('word02').value;
	var width = document.getElementById('width').value;
	var height = document.getElementById('height').value;
	if (word1.length <= 0) {
		document.getElementById('status').innerHTML = 'Minimum of two words required';
		return;
	}
	if (word2.length <= 0) {
		document.getElementById('status').innerHTML = 'Minimum of two words required';
		return;
	}
	if (width.length <= 0) {
		document.getElementById('status').innerHTML = 'Value <b>width</b> required';
		return;
	}
	if (height.length <= 0) {
		document.getElementById('status').innerHTML = 'Value <b>height</b> required';
		return;
	}
	if (!IsNumeric(width)) {
		document.getElementById('status').innerHTML = 'Value <b>width</b> needs numeric input';
		return;
	}
	if (!IsNumeric(height)) {
		document.getElementById('status').innerHTML = 'Value <b>height</b> needs numeric input';
		return;
	}
	//tests ok
	document.getElementById('status').innerHTML = ' ';
	//download image visible and form invisible
	document.getElementById('loading').style.visibility = 'visible';
	document.getElementById('form1').style.visibility = 'hidden';
	//document.getElementById('inpNrs').style.visibility = 'hidden';

	//go for it!
	document.getElementById('form1').submit();
}
