var le_haut= document.getElementById('haut');
le_haut.style.backgroundImage="url('images/chambres.jpg');";
var formulaire=document.getElementById('f');
var depart=document.getElementById('champ');
var valeur_depart=depart.value;
le_haut.style.backgroundPosition= valeur_depart+"px -1px";
var i=valeur_depart;

function move()
{
    var le_haut= document.getElementById('haut');
    le_haut.style.backgroundPosition= i+"px -1px";
    depart.value= i--;
    setTimeout('move()',1);
}