function rollImg(img) {
  var baseSrc = img.src.replace(/_on/, "");
  img.src = (img.src.indexOf("_on") != -1) ? baseSrc : baseSrc.replace(/.gif/, "_on.gif");
}

function showTitle(img) {
  var baseSrc = (img != null) ? img.src.substring(0, img.src.lastIndexOf("/")) : null;
  document.getElementById("eyecon").style.visibility = (img != null) ? "visible" : "hidden";
  var titleImg = document.getElementById("titles").firstChild;
  while (titleImg != null) {
    if (titleImg.nodeName == "IMG") {
      titleImg.style.display = (titleImg.src.indexOf(baseSrc) != -1) ? "" : "none";
    }
    titleImg = titleImg.nextSibling;
  }
}