function isWindowOpen(windowhandle){
	if (windowhandle && windowhandle.open && !windowhandle.closed){
		return true;
	} else {
		return false;
	}
}			


var imgWin;
function openImageWindow(w,h,s)
{
	//var newWindowURL = unescape(url);
	var maxw=0;
	var maxh=0;
	var winsize=0;
	var ratio = w/h;
	var hgt,wid;
	if(w>350 || h>350){
		if(ratio <=1) {
			h = 350;
			w = h*ratio;
		} else {
			w = 350;
			h = w*(1/ratio);
		}
	} 
	
	hgt = h;
	wid = w;
		
	
	
	var newWindowURL = "prod_image_viewer.php?h="+hgt+"&w="+wid+"&src="+s;
	if (!isWindowOpen(imgWin))		
	{
		imgWin = window.open(newWindowURL,"imgWindow","resizable=yes,address=no,scrollbars=no,height="+hgt+",width="+wid);
	}
	else
	{
		imgWin.location = newWindowURL;
		imgWin.focus();
	}	
	
}