public function getImageQuery()
    {
        $command = '';

        foreach($this->effect as $effect)
        {
            if($effect instanceof PictureEffect)
            {
                $command .= $effect->__toString() . '&';
            }
        }

        $command .= 'Quality;' . $this->quality . '&';

        if($this->progressive)
        {
            $command .= 'Progressive&';
        }

        return substr($command, 0, strlen($command) - 1);
    }