var xPos = 300;
var yPos = 200; 
var step = 1;
var delay = 30; 
var height = 0;
var Hoffset = 0;
var Woffset = 0;
var yon = 0;
var xon = 0;
var pause = true;
var interval;
function changePos() 
{
	width = 680;
	height = 350;
	Hoffset = img1.offsetHeight;
	Woffset = img1.offsetWidth;
	img1.style.left = xPos + 230;
	img1.style.top = yPos + 140;
	if (yon) 
		{yPos = yPos + step;}
	else 
		{yPos = yPos - step;}
	if (yPos < 0) 
		{yon = 1;yPos = 0;}
	if (yPos >= (height - Hoffset)) 
		{yon = 0;yPos = (height - Hoffset);}
	if (xon) 
		{xPos = xPos + step;}
	else 
		{xPos = xPos - step;}
	if (xPos < 0) 
		{xon = 1;xPos = 0;}
	if (xPos >= (width - Woffset)) 
		{xon = 0;xPos = (width - Woffset);   }
}
	
	function start()
	{
		var itl = setInterval("changePos()", delay)
		img1.onmouseover = function() { clearInterval(itl) }
		img1.onmouseout = function() { itl = setInterval("changePos()", delay) }
	}
	
	start();