Hola Eboy.
Lo que digo lo entenderás mejor si estudias este código:
Código PHP:
<html>
<head>
<script language="JavaScript">
var aImagen = new Array("001.jpg", "002.jpg", "003.jpg", "004.jpg", "005.jpg", "006.jpg", "007.jpg");
var aWidth = new Array(274, 269, 248, 263, 268, 258, 261);
var aHeight = new Array(204, 153, 313, 157, 141, 178, 182);
banner = 0;
function cambiaBanner(){
with (document.frm.miBanner){
src = aImagen[banner];
width = aWidth[banner];
height = aHeight[banner];
banner++;
if (banner == aImagen.length) banner = 0;
}
setTimeout("cambiaBanner()", 5000);
}
</script>
</head>
<body onload="cambiaBanner()">
<form name="frm">
<center>
<img name="miBanner" border="0"><br>
</center>
</form>
</body>
</html>
Saludos.