$(".imagesBaniere").click(function () {
    $('.imagePrincipaleBaniere').attr('src', $(this).attr('src'));

});

var nbPixelDecalage = 69;
var hauteurImages = $('.ligneDiaporama').length * nbPixelDecalage;
var positionDiapo = 198;

$(".css_arrow_up").click(function () {
    positionDiapo -= nbPixelDecalage;
    if (positionDiapo < 198) {
        positionDiapo = 198;
    }

    if (window.$("#blocDiapoMove").offset().top < 58) {
        window.$("#blocDiapoMove").animate({ "margin-top": "+=69px" }, "fast");
    }

});

$(".css_arrow_down").click(function () {

    positionDiapo += nbPixelDecalage;

    if (positionDiapo < hauteurImages + 1) {
        $("#blocDiapoMove").animate({ "margin-top": "-=69px" }, "fast");
    }
});