/* settings */
var showDuration = 7000;
var container = $('secondary-content').getElement('.whitedragon-content');
var images = container.getElements('img');
var currentIndex = 0;
var interval;
/* opacity and fade */
images.each(function(img,i){ 
    if(i > 0) {
        img.set('opacity',0);
    }
});

/* worker */
var show = function() {
    new Fx.Tween(images[currentIndex], {
    	duration: 1000,
    	onComplete: function() {
    	    new Fx.Tween(images[currentIndex = currentIndex < images.length - 1 ? currentIndex+1 : 0], {
    	    	duration: 1000
			}).start('opacity', 0, 1);
		}
	}).start('opacity', 1, 0.01);
};

if(images.length > 1) {
	interval = show.periodical(showDuration);
}