无法使用phptube类下载youtube视频

我正在使用phptube类下载您的tube视频。

from this site

在代码中,我将youtube url粘贴到一个输入框上,但下面有错误。

Warning: file_get_contents(http://www.youtube.com/get_video?video_id=&t=)
[function.file-get-contents]: failed to open stream: HTTP request failed! 
HTTP/1.0 404 Not Found

和

Warning: file_put_contents(./flvs/3Hx9VsqMUug.flv) [function.file-put-contents]:
failed to open stream: No such file or directory in E:\xampp\htdocs\vdo\utube
\functions.php on line 19
path:./flvs/3Hx9VsqMUug.flv

请告诉我哪里有问题???

更新:

$url = "http://www.youtube.com/watch?v=".$video_id;
            //where $video_id=nlZJ7RsyC0g
    $this->req =& new HTTP_Request($url);
    //echo "<pre>";
    //print_r($this->req);
    //echo "</pre>";
    //die;
    $response = $this->req->sendRequest();
    //echo $response; die;
    if (PEAR::isError($response)) {
        //echo "inside if";
        $response->getMessage()."\n";
    } else {    
        //echo "inside else";
        $page = $this->req->getResponseBody();  
        //print_r($page);
        //var_dump($page);
        //die;
        preg_match("/video_id=(\w*)/",$page,$mv);

        $v_id = $mv[1]; 

        preg_match("/&t=([\w]*)&/",$page,$tickets);
        $ticket = $tickets[1];

        $curl = "";
        $curl .= $v_id;
        $curl .= "&t=";
        $curl .= $ticket;
        //echo $curl;
        $url = "http://www.youtube.com/get_video?video_id=".$curl;
        echo $url;
        die;
        if ($this->debug)
        return $url;    

输出($url)是 http://www.youtube.com/get_video?video_id=nlZJ7RsyC0g&t=

$t 为空,如何获取 $ticke 来自youtube url的t