public function getSegmentCount($pageNumber = '', $fragmentNumber = '')
    {


        if ($pageNumber == '')
            throw new Exception('page number not specified');

        if ($fragmentNumber == '')
            throw new Exception('fragment number not specified');


        $strURI = Product::$baseProductUri . '/pdf/' . $this->getFileName() . '/pages/' . $pageNumber . '/fragments/' . $fragmentNumber;

        $signedURI = Utils::sign($strURI);

        $responseStream = Utils::processCommand($signedURI, 'GET', '', '');

        $json = json_decode($responseStream);

        return count($json->TextItems->List);
    }