var arrImg = [
"/i/intl/champ.jpg",
"/i/intl/welcome01.jpg",
"/i/intl/agir.jpg",
"/i/intl/welcome02.jpg",
"/i/intl/champpak.jpg",
"/i/intl/welcome03.jpg",
"/i/intl/agirpak.jpg"];

function rotate(){
  var iCnt=arrImg.length;
  for(var i=0;i<arrImg.length;i++){
    var newImg = new Image();
    newImg.src = arrImg[i];
    var n = Math.floor(Math.random()*iCnt);
    if(n!=i){
      var xImg = arrImg[n];
      arrImg[n] = arrImg[i];
      arrImg[i] = xImg;
    }
  }
}
var nextImg = 0;
function setTabBg(){
  var theTab = document.getElementById("myTab");
  theTab.style.backgroundImage="url("+arrImg[nextImg]+")";
  nextImg++;
  if(nextImg>=arrImg.length){
    nextImg=0;
    rotate();
  }
  setTimeout(setTabBg, 1000000);
}
rotate();