PDF print Logo or not

[adhi]

Hi, in the PDF.php file I’m trying to only print logo when delivery.firstname is equal to invoce.firstname
so I try code like this

$invoice_address = new Address(intval(self::$order->id_address_invoice));
$delivery_address = new Address(intval(self::$order->id_address_delivery));

if (file_exists(PS_IMG_DIR.’/logo.jpg’)) AND (($delivery_address->firstname)<>($invoice_address->firstname)) $this->Image(PS_IMG_DIR.’/logo.jpg’, 10, 8, 0, 15);

but it’s error (blank)
thank all