PHP image synthesis

<?php
===================== Create a new GD image stream and output the image ========================
Header ("Content-type:image/png");
function Combine_image ($image 1, $image 2, $opt = 100) {
$wimage _data = getimagesize ($image 1);
$width _im1 = $wimage _data[0];
$height _im1 + = $wimage _data[1];

Switch ($wimage _data[2]) {
Case 1:
$im 1 = @ImageCreateFromGIF ($image 1);
Break

Case 2:
$im 1 = @ImageCreateFromJPEG ($image 1);
Break

Case 3:
$im 1 = @ImageCreateFromPNG ($image 1);
Break
}
$wimage _data = getimagesize ($image 2);
$width _im2 = $wimage _data[0];
$height _im2 + = $wimage _data[1];

$width = min ($width _im1, $width _im2);
$height = $height _im1 + $height _im2;
Switch ($wimage _data[2]) {
Case 1:
$im 2 = @ImageCreateFromGIF ($image 2);
Break

Case 2:
$im 2 = @ImageCreateFromJPEG ($image 2);
Break

Case 3:
$im 2 = @ImageCreateFromPNG ($image 2);
Break
}

$im = Imagecreatetruecolor ($width, $height);
$white = Imagecolorallocatealpha ($im, 255, 255, 255, 127);
Imagefill ($im, 0, 0, $white);

Imagecopy ($im, $im 1, 0, 0, 0, 0, $width, $height _im1);
Imagecopy ($im, $im 2, 0, $height _im1, 0, 0, $width, $height _im2);
//================================================
Header (' Content-type:image/jpeg ');
Imagejpeg ($im, "tpn.jpg");
$output _image = Str_replace ('. ', ' _email. ', $image 1);
Imagedestroy ($im);
Imagedestroy ($im 1);
Imagedestroy ($im 2);
Imagedestroy ($im 3);
Imagedestroy ($im _small);

}
Combine_image (' 11.jpg ', ' 1.jpg ');
?>

PHP image synthesis