<?php
//LolRotator
$images = array();
//set allowed images
$allowed = array('image/jpg', 'image/png', 'image/gif', 'image/tiff');
//choose directory. set to current.
$dirPath = '.';
if ($handle = opendir($dirPath)) {
    //read all the files
   // keep reading the directory entries 'til the end
   while (false !== ($file = readdir($handle))) {
           if ($file != "." && $file != ".." && $file != 'Thumbs.db' && $file != '.htaccess' && $file != 'image.php') {
           //make sure it's a file, not directory
            if(is_dir($file) == false) {
            //get info
            $get = getimagesize($file);
            //get mime type from above
            $mimetype = $get['mime'];
                //'tis allowed?
                if(in_array($mimetype, $allowed)) {
                    //add to array
                    $images[] = $file;
                    }
            }
        }
    }
    //close
    closedir($handle);
}
//which one?
$show = mt_rand(0, (count($images)-1));
//turn stuff into images.
header('Content-Type: image/png');
//display
$image = imagecreatefrompng($images[$show]);
imagepng($image);
imagedestroy($image);
?>

Fatal error: Call to undefined function imagecreatefrompng() on line 35