public function __construct(TCPDF $pdf, $imageFilename, $imagePaddingX = 0, $imagePaddingY = 0)
 {
     parent::__construct($pdf);
     $this->imageFilename = $imageFilename;
     $this->imagePaddingX = $imagePaddingX;
     $this->imagePaddingY = $imagePaddingY;
 }