Here is an easy to use PHP barcode generator class for code 39 barcodes.

PHP Barcode Generator Class Code 39

This package can be installed easily using Composer. Simply add the following to the composer.json file at the root of your project:

{
  "require": {
    "fobiaweb/barcode39": "*"
  }
}

Then install your dependencies using composer.phar install.

PHP Web server and GD Library (Graphics Library).

The PHP class will create a GIF barcode image or save a GIF barcode image file, here is an example:

// include Barcode39 class 
include "Barcode39.php"; 

// set Barcode39 object 
$bc = new Barcode39("Shay Anderson"); 

// display new barcode 
$bc->draw();

This example will output this barcode:

You can also easily adjust the barcode bar sizes and text size:

// set object 
$bc = new Barcode39("123-ABC"); 

// set text size 
$bc->barcode_text_size = 5; 

// set barcode bar thickness (thick bars) 
$bc->barcode_bar_thick = 4; 

// set barcode bar thickness (thin bars) 
$bc->barcode_bar_thin = 2; 

// save barcode GIF file 
$bc->draw("barcode.gif");

This example will save this barcode as "barcode.gif":