/**
  * Loads assets from an QTI object element
  * @param QtiObject $object the object
  */
 private function loadObjectAssets(QtiObject $object)
 {
     $type = $object->attr('type');
     if (strpos($type, "image") !== false) {
         $this->addAsset('img', $object->attr('data'));
     } else {
         if (strpos($type, "video") !== false || strpos($type, "ogg") !== false) {
             $this->addAsset('video', $object->attr('data'));
         } else {
             if (strpos($type, "audio") !== false) {
                 $this->addAsset('audio', $object->attr('data'));
             } else {
                 if (strpos($type, "text/html") !== false) {
                     $this->addAsset('html', $object->attr('data'));
                 }
             }
         }
     }
 }