window.onload = init;

function init() {
  addEventHandlers();
  preload();
}

function addEventHandlers() {    
  var imgs = document.getElementById('masthead').getElementsByTagName('img');
  for (i=0; i<imgs.length; i++) {
    imgs[i].onmouseover = addmouseover;
    imgs[i].onmouseout = addmouseout;        
  }
}      

function addmouseover() {        
  this.src = this.src.substring(0,this.src.lastIndexOf('.')) + "_over.gif";         
}

function addmouseout() {
  this.src = this.src.substring(0,this.src.lastIndexOf('_')) + ".gif";          
}

function preload() {
  var pic1 = new Image();
  var pic2 = new Image();
  var pic3 = new Image();
  var pic4 = new Image();
  pic1.src = "../media/images/farsi_over.gif";
  pic2.src = "../media/images/chinese_over.gif";
  pic3.src = "../media/images/korean_over.gif";
  pic4.src = "../media/images/english_over.gif";
}