var coeff=4;//Coefficient de reduction
var larg=740;//largeur maxi de l'image
var haut=555;//hauteur maxi de l'image
var coeffinit=coeff;

function changer() {
	if (document.image.width < larg) {
		coeff = coeff-0.2;
		document.image.width = Math.round(larg/coeff);
		document.image.height = Math.round(haut/coeff);
		chang=window.setTimeout('changer();',60);//vitesse de l'effet
	}
	else {window.clearTimeout(chang);}
	}
	
function initial() {
	if (document.image.width > larg/coeffinit) {
		window.clearTimeout(chang);
		coeff = coeff+0.2;
		document.image.width = Math.round(larg/coeff);
		document.image.height = Math.round(haut/coeff);

		initi=window.setTimeout('initial();',60);//vitesse de l'effet
	}
	else {window.clearTimeout(initi);}
}

function fenetreCent(url,nom,largeur,hauteur,options) {
	var haut=(screen.height-hauteur)/2;
	var Gauche=(screen.width-largeur)/2;
	fencent=window.open(url,nom,"top="+haut+",left="+Gauche+",width="+largeur+",height="+hauteur+","+options);
}