Dynamic signature. - PHP Code Bank

                <?PHP
/*
Files should be named sig[number].png, as in sig0.png.
They should be in the same directory as this php file.
You could implement $dir varibale to fix this.
Also loop through the dir and make array of image files.
I tried didn't work immediately so naturally I gave up :D
*/
header('Content-Type: image/png');
$file = mt_rand(0,4);
$im = imagecreatefrompng("sig$file.png");
imagesavealpha( $im, true );
imagepng($im);
imagedestroy($im);
?>