if (document.images) {
  var image_url = ['bar2_bg', 'bar2_pointer', 'bar2_pointer_center', 'bar2_pointer_left', 'bar2_pointer_right', 'bar_bg', 'bar_pointer', 'bg', 'border_bl', 'border_br', 'border_tl', 'border_tr', 'delete', 'delete_active', 'move_down', 'move_down_active', 'move_up', 'move_up_active', 'mute_off', 'mute_on', 'next', 'next_down', 'next_over', 'pause', 'pause_down', 'pause_over', 'play', 'play_down', 'play_over', 'previous', 'previous_down', 'previous_over', 'repeat_all', 'repeat_off', 'shuffle_off', 'shuffle_on', 'volumeDown', 'volumeDown_down', 'volumeDown_over', 'volumeUp', 'volumeUp_down', 'volumeUp_over', 'save', 'save_down', 'save_over', 'save_as', 'save_as_down', 'save_as_over', 'new', 'new_down', 'new_over', 'open', 'open_down', 'open_over'];
  var preload_image_object = new Array();
  for (var i=0; i<image_url.length; i++) {
    preload_image_object[i] = new Image();
    preload_image_object[i].src = RUTA + 'images/playlist_' + image_url[i] + '.gif';
  }
}