function slideSwitch() {
    var $active = $('#banner-img .active');

    if ( $active.length == 0 ) $active = $('#banner-img .img:last');

    var $next =  ($active.next().length != 0) ? $active.next() : $('#banner-img .img:first');

    $active.addClass('last-active');

    $next.css({opacity: 0.0}).addClass('active').animate({opacity: 1.0}, 1000, function() {
      $active.removeClass('active last-active');
    });
}

$(document).ready(function(){
    setInterval( "slideSwitch()", 5000 );
});