From http://www.emoticode.net/php/generate-qr-codes-with-metadata.html

geenrate_qr_codes_with_metadata.php

 1 <?php 
 2 function qr_code($data, $type = "TXT", $size ='150', $ec='L', $margin='0') 
 3 {
 4     $types = array("URL" => "http://", "TEL" => "TEL:", "TXT"=>"", "EMAIL" => "MAILTO:");
 5     if(!in_array($type,array("URL", "TEL", "TXT", "EMAIL")))
 6     {
 7         $type = "TXT";
 8     }
 9     if (!preg_match('/^'.$types[$type].'/', $data)) 
10     {
11         $data = str_replace("\\", "", $types[$type]).$data;
12     }
13     $ch = curl_init();
14     $data = urlencode($data); 
15     curl_setopt($ch, CURLOPT_URL, 'http://chart.apis.google.com/chart');
16     curl_setopt($ch, CURLOPT_POST, true);
17     curl_setopt($ch, CURLOPT_POSTFIELDS, 'chs='.$size.'x'.$size.'&cht=qr&chld='.$ec.'|'.$margin.'&chl='.$data);
18     curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
19     curl_setopt($ch, CURLOPT_HEADER, false);
20     curl_setopt($ch, CURLOPT_TIMEOUT, 30);
21 
22     $response = curl_exec($ch);
23 
24     curl_close($ch);
25     return $response;
26 }
27 
28 header("Content-type: image/png");
29 echo qr_code("http://emoticode.net", "URL");
30 
31 ?>