How to generate barcode as image and save to my server?

Question

I’m creating a Landing page where the user registers and a barcode will be generated that is sent via email to the user on a discount coupon, I am using the library Barcode.inc.php to generate the barcode image, I need to save this image to my server to use when sending the email, as I could do this?

This is my code:

require_once('barcode.inc.php'); 
$code_number = '125689365472365458';//125689365472365458 
new barCodeGenrator($code_number,0,'hello.gif', 190, 130, true);