var myBannerList = new Array();
var interval_banner_which = new Array();
var interval_banner_1;
var interval_banner_2;
var interval_banner_3;
var interval_banner_4;
var myNewBanner;

function startBannerRotation(){
    interval_banner_1 = setInterval("changeBanner(1);",20000);
    interval_banner_2 = setInterval("changeBanner(2);",20000);
    interval_banner_3 = setInterval("changeBanner(3);",20000);
    interval_banner_4 = setInterval("changeBanner(4);",20000);
}

function changeBanner(myPosition){
    if(myBannerList[myPosition].length > 1){
        interval_banner_which[myPosition] = interval_banner_which[myPosition] + 1;
        if(interval_banner_which[myPosition] >= myBannerList[myPosition].length) interval_banner_which[myPosition] = 0;
        
        myNewBanner = myBannerList[myPosition][interval_banner_which[myPosition]];
        myNewBanner = myNewBanner.replace(/_<_/g, '<');
        myNewBanner = myNewBanner.replace(/_>_/g, '>');
        
        document.getElementById('banners_image_slideshow_td_' + myPosition).innerHTML = myNewBanner;
    }
}