var aInterval;
var bInterval;
var nowimg=0;
var alpha1,alpha2;


function alphaup(id,alpha){
    clearInterval(aInterval);
    //var target=document.getElementById("id")[0];
    aInterval=setInterval("add('"+id+"',"+alpha+")",30);
}

function add(obj,alpha)
{
    var target=document.getElementById(obj);
    var step=3;
    if(target.style.opacity>=alpha/100)
    {
    clearInterval(aInterval);
    aInterval=false;
    }
    else{
        
        if("\v"=="v") target.filters.Alpha.Opacity += step;
        target.style.opacity = Number(target.style.opacity)+step/100;
        
    }
}



function alphadown(id,alpha){
    clearInterval(bInterval);
    //var target=document.getElementById("id")[0];
    bInterval=setInterval("cut('"+id+"',"+alpha+")",30);
}

function cut(obj,alpha)
{
    var target=document.getElementById(obj);
    var step=3;
    if(target.style.opacity<=alpha/100)
    {
    clearInterval(bInterval);
    bInterval=false;
    }
    else{
        
        if("\v"=="v") target.filters.Alpha.Opacity -= step; 
        target.style.opacity-=step/100;
    }
}


function nextimg()
{   
    alphadown("bannerimg"+nowimg,0);
    
    if(nowimg==4) nowimg=0;
    else nowimg++;
    alphaup("bannerimg"+nowimg,99);
}