Compte à rebours en javascript

<script language="JavaScript">
var i;
var picfiles; var pictime;
function preload_pic(){
    picfiles=preload_pic.arguments;
    pictime=new Array();
    for (i=0; i<picfiles.length; i++) {
          pictime[i]=new Image;
          pictime[i].src=picfiles[i];}
}
--></script>
<script language="JavaScript"><!--
preload_pic("rebours/g0.png","rebours/g1.png","rebours/g2.png","rebours/g3.png","rebours/g4.png","rebours/g5.png","rebours/g6.png","rebours/g7.png","rebours/g8.png","rebours/g9.png");
--></script>           
                <script language="JavaScript">
                
                function t()
                {
            var compteur=document.getElementById('compteur');
            s=duree;
            m=0;h=0;
            if(s<0)
                        {
                                window.location.replace("index.php?id2=<?php echo $id2 ?>");
            }
                        else
                        {
                                if(s>59)
                                {
                                        m=Math.floor(s/60);
                                        s=s-m*60
                }
                                if(m>59)
                                {
                                        h=Math.floor(m/60);
                    m=m-h*60
                                }
               var mm= m;
         if (mm<10) {pmm='<img src='+picfiles[0]+' height=41px><img src='+picfiles[mm]+' height=41px>';}
         if (mm>9) {
             mm=mm.toString();
             pmm='<img src='+picfiles[(mm.substr(0,1))]+' height=41px><img src='+picfiles[(mm.substr(1))]+' height=41px>';}
   var ss= s;
         if (ss<10) {pss='<img src='+picfiles[0]+' height=41px><img src='+picfiles[ss]+' height=41px>';}
         if (ss>9) {
             ss=ss.toString();
             pss='<img src='+picfiles[(ss.substr(0,1))]+' height=41px><img src='+picfiles[(ss.substr(1))]+' height=41px>';}
	           compteur.innerHTML=pss;
            }
            duree=duree-1;
            window.setTimeout("t();",999);

        }
</script>                
                
                <script language="JavaScript">
                        duree="60";
                        t();
                </script>
				</div>
				<br/>