JavaScript DHTML/Event onMethod/onMouseWheel
"onMouseWheel" Example
<html>
<body>
<p>Move mouse in and move the mouse wheel up or down.</p>
<img id="yourimage"
src="http://www.wbex.ru/style/logo.png"
width="500"
height="500"
onmousewheel="alert("Wheel Delta: " + event.wheelDelta);">
</body>
</html>