Style

html :
<section id="anim">
   <img id="denis" src="https://www.ibisc.univ-evry.fr/~dupont/Images/denis.jpg" alt="me">

</section>

js :

let me = --?-- ;
let body = --?-- ;
let angle = 0, lastTime = null;

let bodyW = body.getBoundingClientRect().width,
    bodyMe = me.getBoundingClientRect().width;


function animate(time) {
   if (lastTime != null)
       angle+= (time - lastTime)* 0.001;
    lastTime = time;

    --?--  = (Math.cos(angle)* (bodyW-bodyMe)/2)+"px";
    --?--  = --?--

    requestAnimationFrame(animate);
}

requestAnimationFrame(animate);