var divId_a;
var divId_b;
var contentHTML;
var contentNumber;
var slideTimeout;

function initSlide(div_a, div_b, contentArray, displaySecs) {
	divId_a = div_a;
	divId_b = div_b;
	contentNumber = -1;
	contentHTML = contentArray;
	runSlide(1, displaySecs);
}

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 + ")"; 
} 

function blendDiv(content, millisec) { 
	var speed = Math.round(millisec / 10); 
	
	//set the current content as underlying layer 
	document.getElementById(divId_a).innerHTML = document.getElementById(divId_b).innerHTML; 
	
	//make image transparent 
	changeOpac(0, divId_b); 
	
	//make new image 
	document.getElementById(divId_b).innerHTML = content; 
	
	//fade in image 
	for(i = 0; i <= 100; i++)
		setTimeout("changeOpac(" + i + ",'" + divId_b + "')",(i * speed)); 
} 

function runSlide(step, displaySecs) {
	contentNumber = (contentNumber + step) % contentHTML.length; 
	if (contentNumber < 0)
		contentNumber += contentHTML.length;
	changeOpac(0, divId_b); 
	blendDiv(contentHTML[contentNumber], 30); 
	
	if (displaySecs > 0 && contentHTML.length > 1)
		slideTimeout = setTimeout("runSlide("+step+","+displaySecs+")",displaySecs*1000);
}

function stopSlide() {
	if (slideTimeout)
		clearTimeout(slideTimeout);
	slideTimeout = null;
}