function showMask(file)
	{
		var height = document.getElementById('footer').offsetTop;
		document.getElementById('mask').style.display = "block";
		document.getElementById('mask').style.height = (height + 100)+"px";
		
		if (navigator.appName == "Microsoft Internet Explorer")
			{
				position = document.documentElement.scrollTop;
				position = position + 100;
				document.getElementById('popup').style.top = position+"px";
			}
		else
			{
				position = window.pageYOffset;
				position = position + 100;
				document.getElementById('popup').style.top = position+"px";
			}

		document.getElementById('popup').style.display = "block";
		document.getElementById('popup').style.top = position+"px";
		document.getElementById('bigImg').src = file;
	}
function hideMask()
	{
		document.getElementById('mask').style.display = "none";
		document.getElementById('popup').style.display = "none";
	}
	
function imagePreload(folder, nbImg)
	{
		var i = 0;
		var j = 0;
		
		imageObj = new Image();
		images = new Array();
		for(i=0; i!=nbImg; i++)
			{
				images[i] = folder+i+".jpg"
			}
			
		for(j=0; j!=nbImg; j++)
			{
				imageObj.src=images[i];
			}
	}