PHP class library for generating QR codes (QRCode method)

include "phpqrcode/phpqrcode.php";
$value="http://bbs.it-home.org";
$errorCorrectionLevel = "L";
$matrixPointSize = "4 ";
QRcode::png($value, false, $errorCorrectionLevel, $matrixPointSize);
exit;
?>

File output QR code:

< ?php
include('phpqrcode/phpqrcode.php');
// QR code data
$data = 'http://s.bookphone.cn';
// Generated file name
$filename = '1111 .png';
// Error correction level: L, M, Q, H
$errorCorrectionLevel = 'L';
// Point size: 1 to 10
$matrixPointSize = 4;
QRcode::png($data , $filename, $errorCorrectionLevel, $matrixPointSize, 2);
?>

to generate a QR code with a logo in the middle:

//QR code with middle logo
//by bbs.it-home.org
include('phpqrcode/phpqrcode.php');
$ value='http://bbs.it-home.org';
$errorCorrectionLevel = 'L';
$matrixPointSize = 6;
QRcode::png($value, 'jbxue.png', $errorCorrectionLevel, $matrixPointSize , 2);
echo "QR code generated"."";
$logo = 'logo.png';
$QR = 'jbxue.png';

{
$QR = imagecreatefromstring(file_get_contents($QR));
$logo = imagecreatefromstring(file_get_contents($logo));
$QR_width = imagesx($QR);
$QR_height = imagesy($QR);
$logo_width = imagesx($logo);
$logo_height = imagesy($logo);
$logo_qr_width = $QR_width / 5;
$scale = $logo_width / $logo_qr_width;
$logo_qr_height = $logo_height / $scale;
$from_width = ($QR_width - $logo_qr_width) / 2;
imagecopyresampled($QR, $logo, $from_width, $from_width, 0, 0, $ logo_qr_width, $logo_qr_height, $logo_width, $logo_height);
}
imagepng($QR,'jbxue_log.png');
?>