public function outputThumbnail($format = 'png', $quality = 75)
{
parent::setOutputFormat($format);
//parent::setCache();
/*
if ($this->cache_time === 0 || $this->cache->isPictureCached() === FALSE) {
$this->createThumbnail();
if ($this->cache_time > 0) {
$this->cache->writePictureCache($this->thumbnail, 100);
} // end if
} // end if
*/
parent::outputThumbnail($format, $quality);
}