I am converting PDF to html using gufy/pdf-to-html package on GitHub . But it showing error that: Undefined array key "pages"

Question

the controller code is below

public function generate(Request $req)
    {
        Config::set('pdftohtml.bin', 'C:/poppler-0.37/bin/pdftohtml.exe');
        Config::set('pdfinfo.bin', 'C:/poppler-0.37/bin/pdfinfo.exe');
        $pdf = new Pdf('document.pdf');
        $pdfDom = $pdf->getDom(['ignoreImages' => true]);   
        $html = $pdf->html();
        $total_pages = $pdf->getPages();
        $html->goToPage(1);
        $paragraphs = $html->find('body > p');

}

any help would be appreciated.