PHP怎么获取视频总时长的函数方法

//获得视频文件的总长度时间和创建时间 根据视频长度判断是否失效
public function getTime($url)
{
  //获取视频重定向后的链接
  $location = locationUrl($url);
  //获取视频Content-Length
  $responseHead = get_data($location);
  $list1 = explode("Content-Length: ", $responseHead);
  $list2 = explode("Connection", $list1[1]);
  $list = explode("x", $list2[0]);
  return $list[0];
}
//获取视频重定向后的链接
function locationUrl($url){
  $url_parts = @parse_url($url);
  if (!$url_parts) return false;
  if (!isset($url_parts['host'])) return false;
  if (!isset($url_parts['path'])) $url_parts['path'] = '/';
  $sock = fsockopen($url_parts['host'], (isset($url_parts['port']) ? (int)$url_parts['port'] : '80'), $errno, $errstr, 30);
  if (!$sock) return false;
  $request = "HEAD " . $url_parts['path'] . (isset($url_parts['query']) ? '?'.$url_parts['query'] : '') . " HTTP/1.1rn";
  $request .= 'Host: ' . $url_parts['host'] . "rn";
  $request .= "Connection: Closernrn";
  fwrite($sock, $request);
  $response = '';
  while(!feof($sock)) {
    $response .= fread($sock, 8192);
  }
  fclose($sock);
  if (preg_match('/^Location: (.+?)$/m', $response, $matches)){
    if ( substr($matches[1], 0, 1) == "/" ){
      return $url_parts['scheme'] . "://" . $url_parts['host'] . trim($matches[1]);
    }
    else{
      return trim($matches[1]);
    }
  } else {
    return false;
  }
}
//审核视频 curl
function get_data($url){
  $oCurl = curl_init();
  //模拟浏览器
  $header[] = "www.zjkweiqi.cn";
  $user_agent = "Mozilla/4.0 (Linux; Andro 6.0; Nexus 5 Build) AppleWeb/537.36 (KHTML, like Gecko)";
  curl_setopt($oCurl, CURLOPT_URL, $url);
  curl_setopt($oCurl, CURLOPT_HTTPHEADER,$header);
  curl_setopt($oCurl, CURLOPT_HEADER, true);
  curl_setopt($oCurl, CURLOPT_NOBODY, true);
  curl_setopt($oCurl, CURLOPT_USERAGENT,$user_agent);
  curl_setopt($oCurl, CURLOPT_RETURNTRANSFER, 1 );
  // 不用 POST 方式请求, 意思就是通过 GET 请求
  curl_setopt($oCurl, CURLOPT_POST, false);
  $sContent = curl_exec($oCurl);
  // 获得响应结果里的：头大小
  $headerSize = curl_getinfo($oCurl, CURLINFO_HEADER_SIZE);
  // 根据头大小去获取头信息内容
  $header = substr($sContent, 0, $headerSize);
  curl_close($oCurl);
  return $header;
}