/** * Draws the barcode. * * @param resource $im */ public function draw($im) { // The following code is exactly the same as EAN13. We just add a 0 in front of the code ! $this->text = '0' . $this->text; // We will remove it at the end... don't worry parent::draw($im); // We remove the 0 in front, as we said :) $this->text = substr($this->text, 1); }