private function boolParams($params)
    {
        if (isset($params['lowquality']) && $params['lowquality']===false)
            $params['lowquality'] = (int) $params['lowquality'];

        if (isset($params['images']) && $params['images']===false)
            $params['images'] = (int) $params['images'];

        if (isset($params['outline']) && $params['outline']===false)
            $params['outline'] = (int) $params['outline'];

        if (isset($params['javascript']) && $params['javascript']===false)
            $params['javascript'] = (int) $params['javascript'];

        if (isset($params['internal_links']) && $params['internal_links']===false)
            $params['internal_links'] = (int) $params['internal_links'];

        if (isset($params['external_links']) && $params['external_links']===false)
            $params['external_links'] = (int) $params['external_links'];

        if (isset($params['use_print_media']) && $params['use_print_media']===false)
            $params['use_print_media'] = (int) $params['use_print_media'];

        if (isset($params['background']) && $params['background']===false)
            $params['background'] = (int) $params['background'];

        return $params;
    }