使用CodeIgniter中的Zend Library在条形码上添加标题

Question

I want to add heading on the barcode like

300 W Fan Heater

on top of my barcode using Zend Library in CodeIgniter

So far I am doing

private function set_barcode($code)
{
    //load library
    $this->load->library('zend');
    //load in folder Zend
    $this->zend->load('Zend/Barcode');
    //generate barcode
    Zend_Barcode::draw('upca', 'image', array('text'=>$code), array());
}

Cant find anything, that add heading on top of barcode