if (document.getElementsByTagName && document.getElementById) {

	var vw = {
		
		// reference to unordered list
		body : document.getElementsByTagName('body')[0],
		
		//timer for the slideshow
		timer : null,
		
		init : function() {
			
			vw.slideshow.setup();
		
		},
		
			
		slideshow : {
		
			setup : function(){
			
				// create object     
				var imageObj = new Image();     
				// set image list     
				vw.slideshow.images = new Array();     
					vw.slideshow.images[0]="images/swooshengage.jpg"     
					vw.slideshow.images[1]="images/swooshranked.jpg"     
					vw.slideshow.images[2]="images/swooshshow.jpg"     
				
				// start preloading  			
				for(var i=0; i<=3; i++){
					imageObj.src=vw.slideshow.images[i];     
				}
			
				vw.slideshow.ssDiv = document.getElementById('mainvid');
												
				vw.slideshow.totalSlides = vw.slideshow.images.length;
						
				vw.slideshow.slideNumber = 0;	
					
				vw.slideshow.start();	
			
			},
				
			//function that will changes the background of the MainVid slides automatically
			forwardSlide : function() {
			
		
				//Makes sure that it is not on the last slide and move forward one slide
				if (vw.slideshow.slideNumber<vw.slideshow.totalSlides-1){
				

					vw.slideshow.slideNumber = vw.slideshow.slideNumber +1;
										
				}
				
				//if on last slide, return to beginning
				else {

					vw.slideshow.slideNumber = 0;
				}
					
				//assigns the src to the iframe
				vw.slideshow.ssDiv.style.backgroundImage = 'url("' + vw.slideshow.images[vw.slideshow.slideNumber] + '")';
												
			},
			
			
			//start timer function
			start : function(){
			
				//runs slideshow every 5 seconds
				this.timer = setInterval('vw.slideshow.forwardSlide()',5000);
			
			},	
	
		},
		
	};

vw.init();

}