if (document.images) {           
img1 = new Image(); img1.src = "anm/01.jpg"; 
img2 = new Image(); img2.src = "anm/02.jpg"; 
img3 = new Image(); img3.src = "anm/03.jpg"; 
img4 = new Image(); img4.src = "anm/04.jpg"; 
img5 = new Image(); img5.src = "anm/05.jpg"; 
img6 = new Image(); img6.src = "anm/06.jpg"; 
img7 = new Image(); img7.src = "anm/07.jpg";
img8 = new Image(); img8.src = "anm/08.jpg";
img9 = new Image(); img9.src = "anm/09.jpg";
img10 = new Image(); img10.src = "anm/10.jpg";
img11 = new Image(); img11.src = "anm/11.jpg";
img12 = new Image(); img12.src = "anm/12.jpg";
img13 = new Image(); img13.src = "anm/13.jpg";
img14 = new Image(); img14.src = "anm/14.jpg";
img15 = new Image(); img15.src = "anm/15.jpg";
img16 = new Image(); img16.src = "anm/16.jpg";
img17 = new Image(); img17.src = "anm/17.jpg";
img18 = new Image(); img18.src = "anm/18.jpg";
img19 = new Image(); img19.src = "anm/19.jpg";
img20 = new Image(); img20.src = "anm/20.jpg";
img21 = new Image(); img21.src = "anm/21.jpg";
img22 = new Image(); img21.src = "anm/22.jpg";
}
var i = 0;
var ismove = 1;
 
function animation() {
	(i<21) ? ++i : i = 1;
	document.animate.src = eval("img" + i + ".src");
	move = setTimeout('animation()', 3000)
}
<!-- 1000=1 sec. Change to vary time //-->

function stop(){
if (ismove==1){
ismove=0;
clearTimeout(move);
}
else {
ismove=1;
animation()
}
}