var ie7=false;
var opac=0;
var grupo1=true;

function inicio(){
	mensaje=navigator.appName;//+parseInt(navigator.appVersion);//+' '+navigator.appVersion.indexOf("MSIE");
	//if(navigator.appVersion.indexOf("MSIE 6")>=0) version='6';
	if(navigator.appVersion.indexOf("MSIE 7")>=0) ie7=true;
	//if(navigator.appVersion.indexOf("MSIE 8")>=0) version='8';	
	grupo1=true ;
	eliminaBaners();
	setInterval('eliminaBaners()',8000);
}


function eliminaBaners(){		
	opac=0;		
	if(grupo1==true){
		element_obj1 = document.getElementById('baner_sup1');
		element_obj2 = document.getElementById('baner_sup2');
		//element_obj3 = document.getElementById('baner_sup3');
		grupo1=false ;
	}else{
		element_obj1 = document.getElementById('baner_sup4');
		element_obj2 = document.getElementById('baner_sup5');
		//element_obj3 = document.getElementById('baner_sup6');
		grupo1=true;
	}		
	IDinterval1= setInterval('fadeOut()',4);
}

function fadeIn(){
		opac++; 
		if (opac==100){ 
			finMuestra();
		}else{ 
			if(ie7){
				element_obj1.style.filter = "alpha(opacity=" + opac + ");"; 
				element_obj2.style.filter = "alpha(opacity=" + opac + ");"; 
				//element_obj3.style.filter = "alpha(opacity=" + opac + ");"; 
			}
		}
		return;
}

function fadeOut(){
		opac++; 
		if (opac==100){ 
			finElimina();
		}else{ 
			if(ie7){
				element_obj1.style.filter = "alpha(opacity=" + (100-opac) + ");"; 
				element_obj2.style.filter = "alpha(opacity=" + (100-opac) + ");"; 
				//element_obj3.style.filter = "alpha(opacity=" + (100-opac) + ");"; 
			}
		}
		return;
}

function muestraBaners(){	
	if(grupo1==true){
		element_obj1 = document.getElementById('baner_sup1');
		element_obj2 = document.getElementById('baner_sup2');
		//element_obj3 = document.getElementById('baner_sup3');
	}else{
		element_obj1 = document.getElementById('baner_sup4');
		element_obj2 = document.getElementById('baner_sup5');
		//element_obj3 = document.getElementById('baner_sup6');
	}

	element_obj1.style.visibility = "visible"; 
	element_obj2.style.visibility = "visible"; 
	//element_obj3.style.visibility = "visible";
	if(ie7){
		element_obj1.style.filter = "alpha(opacity="+opac+")"; 
		element_obj2.style.filter = "alpha(opacity="+opac+")"; 
		//element_obj3.style.filter = "alpha(opacity="+opac+")"; 
	}
	IDinterval2= setInterval('fadeIn()',1);
}

function finElimina(){
		opac=0;
		clearInterval(IDinterval1);		
		element_obj1.style.visibility = "hidden"; 
		element_obj2.style.visibility = "hidden"; 
		//element_obj3.style.visibility = "hidden"; 
		muestraBaners();
}

function finMuestra(){
		opac=100;
		clearInterval(IDinterval2);		
		if(ie7){
			element_obj1.style.filter = "alpha(opacity="+opac+")"; 
			element_obj2.style.filter = "alpha(opacity="+opac+")"; 
			//element_obj3.style.filter = "alpha(opacity="+opac+")"; 
		}
}

setTimeout("inicio()",5000);