function showPic (whichpic) {
 if (document.getElementById) {
  document.getElementById('changeImagesContainer').style.background = "url(" + whichpic.href + ")";
  document.getElementById('changeImagesContainer').style.backgroundPosition = "center center";
  document.getElementById('changeImagesContainer').style.backgroundRepeat = "no-repeat";
  return false;
 } else {
  return true;
 }
}