MPDF Class - Base64 Images

Good afternoon, I'm using an mdpf class to generate the PDF of a file, but when I use a base64 image within a <img> model my image did not appear

Function:

    $date = date("dmYHi");
    $mpdf = new mPDF('','A4',0,'',10,5,7,7,6,6,'L');
    $mpdf->charset_in='windows-1252';
    $mpdf->WriteHTML($modelo);
    $mpdf->Output("boletos/orcamentopdf_".$date.$_GET['id'].".pdf");

Does anyone know how to fix this or write the template with the image in BD?

Note: When generated by the browser everything comes out and beauty! Only using this function that buga!