function popup(url, height, width) {
  window.open(url, '', "height=" + height + ", width=" + width +", resizable=1, scrollbars=1");
}

function add_popup() {
  var links = document.getElementsByTagName('a');
  for (i = 0; i < links.length; ++i) {
    if (links[i].className == "uploadPopup") {
      links[i].href = "javascript:popup('" + links[i].href + "', '400', '480')";
    }
    if (links[i].className == "imagePopup") {
      var image = links[i].firstChild;
      links[i].href = "javascript:popup('" + links[i].href + "', '" + 1.5*image.height + "', '" + 1.5*image.width + "')";
    }
  }
}