Get error when set 'isRemoteEnabled' option in dompdf - php

Question

I am working on Codeigniter3 and using dompdf to generate pdf where I want to use watermark and logo. I set all things but not able to show images on pdf. First I was using img tag in html itself but it was not working so I added the code to apply the appropriate images in Pdf.php file in libraries folder but still it doesn't show images properly.
I did some research on it and found, need to enable 'isRemoteEnabled' option but when I apply this option, it throws error.
Below is my code
Controller function code
$html = $this->load->view('book_quiz_completion_certificate', $this->data, TRUE);
$this->load->library('pdf');
$this->pdf->createPDF($html, $book_title, true);
Pdf function
function createPDF($html, $filename='', $download=TRUE, $paper='A4', $orientation='portrait')
{
// Set options to enable embedded PHP
$options = new Options();
$options->set('isPhpEnabled', 'true');
$options->set('isRemoteEnabled', 'true');
//$options->set('tempDir', __DIR__ . '/site_uploads/dompdf_temp');
//$options->set('isRemoteEnabled', TRUE);
//$options->set('debugKeepTemp', TRUE);
//$options->set('chroot', '/'); // Just for testing :)
//$options->set('isHtml5ParserEnabled', true);
//$domPdf->setOptions($options);
$dompdf = new DOMPDF($options);
$contxt = stream_context_create([
'ssl' => [
'verify_peer' => FALSE,
'verify_peer_name' => FALSE,
'allow_self_signed'=> TRUE
]
]);
//echo '<pre> $options :: '; print_r($dompdf->getOptions()); die;
$dompdf->setHttpContext($contxt);
$dompdf->load_html($html);
$dompdf->set_paper($paper, $orientation);
// Render the HTML as PDF
$dompdf->render();
// Instantiate canvas instance
$canvas = $dompdf->getCanvas();
// Get height and width of page
$w = $canvas->get_width();
$h = $canvas->get_height();
// Specify oogo image
$logo_imageURL = FCPATH.'assets/uploads/images/143b8-f0b8b-86.jpg';
$logo_imgWidth = 20;
$logo_imgHeight = 20;
// Specify logo image horizontal and vertical position
$x = (($w-$logo_imgWidth)/5);
$y = (($h-$logo_imgHeight)/7);
// Add logo image to the pdf
$canvas->image($logo_imageURL, $x, $y, $logo_imgWidth, $logo_imgHeight);
// Specify watermark image
$imageURL = URL_PUBLIC_UPLOADS.'images/143b8-f0b8b-86.jpg';
$imgWidth = 400;
$imgHeight = 400;
// Set text opacity
$canvas->set_opacity(.5);
// Specify watermark image horizontal and vertical position
$x = (($w-$imgWidth)/2);
$y = (($h-$imgHeight)/4);
// Add watermark image to the pdf
$canvas->image($imageURL, $x, $y, $imgWidth, $imgHeight);
// Specify watermark image
$signature_imageURL = URL_PUBLIC_UPLOADS.'images/download.png';
//$signature_imageURL = FCPATH.'assets/uploads/images/download.png';
$signature_imgWidth = 60;
$signature_imgHeight = 60;
//$canvas->set_opacity(.5);
// Specify signature image image horizontal and vertical position
$x = (($w-$signature_imgWidth)/3);
$y = (($h+$signature_imgHeight)/2);
// Add signature image to the pdf
$canvas->image($signature_imageURL, $x, $y, $signature_imgWidth, $signature_imgHeight);
if($download)
$dompdf->stream($filename.'.pdf', array('Attachment' => 1));
else
$dompdf->stream($filename.'.pdf', array('Attachment' => 0));
}
For html, I am using following template
body {
font-family: Roboto;
}
.certificate-container {
padding: 50px;
width: 1024px;
}
.certificate {
border: 20px solid #0C5280;
padding: 25px;
height: 600px;
position: relative;
}
.certificate:after {
content: '';
top: 0px;
left: 0px;
bottom: 0px;
right: 0px;
position: absolute;
background-image: url(https://image.ibb.co/ckrVv7/water_mark_logo.png);
background-size: 100%;
z-index: -1;
}
.certificate-header > .logo {
width: 80px;
height: 80px;
}
.certificate-title {
text-align: center;
}
.certificate-body {
text-align: center;
}
h1 {
font-weight: 400;
font-size: 48px;
color: #0C5280;
}
.student-name {
font-size: 24px;
}
.certificate-content {
margin: 0 auto;
width: 750px;
}
.about-certificate {
width: 380px;
margin: 0 auto;
}
.topic-description {
text-align: center;
}
<div class="certificate-container">
<div class="certificate">
<div class="water-mark-overlay"></div>
<div class="certificate-header">
<img src="https://rnmastersreview.com/img/logo.png" class="logo" alt="">
</div>
<div class="certificate-body">
<p class="certificate-title"><strong>RENR NCLEX AND CONTINUING EDUCATION (CME) Review Masters</strong></p>
<h1>Certificate of Completion</h1>
<p class="student-name">Matthew Taylor</p>
<div class="certificate-content">
<div class="about-certificate">
<p>
has completed [hours] hours on topic title here online on Date [Date of Completion]
</p>
</div>
<p class="topic-title">
The Topic consists of [hours] Continuity hours and includes the following:
</p>
<div class="text-center">
<p class="topic-description text-muted">Contract adminitrator - Types of claim - Claim Strategy - Delay analysis - Thepreliminaries to a claim - The essential elements to a successful claim - Responses - Claim preparation and presentation </p>
</div>
</div>
<div class="certificate-footer text-muted">
<div class="row">
<div class="col-md-6">
<p>Principal: ______________________</p>
</div>
<div class="col-md-6">
<div class="row">
<div class="col-md-6">
<p>
Accredited by
</p>
</div>
<div class="col-md-6">
<p>
Endorsed by
</p>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
Now, Both options for me is ok i.e. if it can allow img tag in html itself or it can add image from function itself.
Any help is really appreciated.
Thanks.