public function brightness($level = self::BRIGHTNESS_MAX)
{
// Don't continue if brightness level is invalid
if (!(self::BRIGHTNESS_MIN <= $level && $level <= self::BRIGHTNESS_MAX)) {
throw new \InvalidArgumentException("Brightness must be between " . self::BRIGHTNESS_MIN . " and " . self::BRIGHTNESS_MAX);
}
$this->params['bri'] = (int) $level;
return $this;
}