php返回文件损坏mp4 readfile访问根目录外的文件夹

Question

我试图在页面上加载mp4文件，但是我收到了损坏的文件消息。

我使用这个作为我的php文件从根目录外的私人文件夹加载并直接从浏览器打开它，看看视频是否直接播放到firefox浏览器：

if(!empty($_GET['video']))
 {
if (strpos($_GET['video'], "\0") !== FALSE) die('');

$video  = $_REQUEST['video'];
$path_parts = pathinfo($video);
$file_name  = $path_parts['basename'];

require_once("config.php");

if(isUserLoggedIn())
{ 
    //Construct an Order object
    $IsPaid = new Order($reference=$loggedInUser -> user_id,$pesapal_tracking_id=NULL,$orderstatus = NULL);

    //Check if he is paid
    if($IsPaid->isPaid())
    {

        //Private folder        
                    $file = $_SERVER['DOCUMENT_ROOT'].'/../privatelogged/'. $file_name;

        header("Expires: Mon, 26 Jul 1997 05:00:00 GMT");
        header("Cache-Control: no-store, must-revalidate");
        header("Content-Type: video/mp4");
        header('Content-Length: ' . filesize($file));

            set_time_limit(0);
            $resource = @fopen($file,"rb");
            while(!feof($resource))
            {
                print(@fread($resource, 1024*8));
                ob_flush();
                flush();
            }

        //readfile($file);


    }
}

}