private function ffprobeFormat($format)
	{
		$this->ffprobe();

		if (count($this->formats) > 0)
		{
			$args = func_get_args();

			foreach ($args as $arg)
			{
				if (in_array($arg, $this->formats))
				{
					return true;
				}
			}

			return null;
		}

		return false;
	}