Change The Image When Mouse Out Using Onmousemove Event In JavaScript

<html>

<head>
    <script type="text/javascript">
        function mouseOver() {
            document.getElementById("b1").src = "Water lilies.jpg";
        }

        function mouseOut() {
            document.getElementById("b1").src = "Sunset.jpg";
        }
    </script>
</head>

<body>
    <a href="Onclick.html" target="_blank"> <img border="0" alt="Visit Onclick!" src="Water lilies.jpg" id="b1" width="260" height="260" onmouseover="mouseOver()" onmouseout="mouseOut()" /></a>
</body>

</html>