var currentBox = "testimonial01";

function popBox(id, opacStart, opacEnd, millisec) {

	document.getElementById(currentBox).style.display="none";
	document.getElementById(id).style.display="block";
	currentBox = id;
	
	//speed for each frame
	var speed = Math.round(millisec / 100);
	var timer = 0;

	//determine the direction for the blending, if start and end are the same nothing happens
	if(opacStart > opacEnd) {
		for(i = opacStart; i >= opacEnd; i--) {
			setTimeout("changeOpac(" + i + ",'" + id + "')",(timer * speed));
			timer++;
		}
	} else if(opacStart < opacEnd) {
		for(i = opacStart; i <= opacEnd; i++)
			{
			setTimeout("changeOpac(" + i + ",'" + id + "')",(timer * speed));
			timer++;
		}
	}
}

function changeOpac(opacity, id) {
	var object = document.getElementById(id).style; 
	object.opacity = (opacity / 100);
	object.MozOpacity = (opacity / 100);
	object.KhtmlOpacity = (opacity / 100);
	object.filter = "alpha(opacity=" + opacity + ")";
}

var imgs = [
    'testimonial01',
    'testimonial02',
    'testimonial03',
    'testimonial04'
];
var forever = function(i) {
    popBox(imgs[i], 0, 100, 1000);
    window.setTimeout('forever(' + ((i + 1) % imgs.length) + ');', 10000);
};