public function getMimeTypeFromFile($file)
	{
		$extension = strtolower(pathinfo($file, PATHINFO_EXTENSION));
		if (array_key_exists($extension, $this->_alt_mime_types)) {
			return $this->_alt_mime_types[$extension];
		} else {
			return (new \Finfo(FILEINFO_MIME_TYPE))->file($file);
		}
	}