playing video 16:9 Aspect Ratio

my player is 16:9, so i trying to get netStream width,height after i playing video Aspect Ratio to 16:9 (like show youtube black side pillers);

but here my code playing video default size 320x240,

can you help me anyone?

My code:

var nConnection:NetConnection;
var ns:NetStream;
var video:Video = new Video();
addChild(video);
  
nConnection = new NetConnection();
nConnection.addEventListener(NetStatusEvent.NET_STATUS, netStatusHandler);
nConnection.addEventListener(SecurityErrorEvent.SECURITY_ERROR, securityErrorHandler);
nConnection.addEventListener(AsyncErrorEvent.ASYNC_ERROR, ayncErrorHandler);
nConnection.connect(serverURL);
 function netStatusHandler(event:NetStatusEvent):void
{
          switch (event.info.code)
          {
                    case "NetConnection.Connect.Success" :
                              connectStream();
                              break;
                    case "NetStream.Play.StreamNotFound" :
                              trace("Stream not found: " + videoURL);
                              break;
                    case "NetStream.Play.Start" :
                              break;
                    case "NetStream.Play.Stop" :
                              break;
                    default :
          }
}
function connectStream():void
{
          ns = new NetStream(nConnection);
          ns.addEventListener(NetStatusEvent.NET_STATUS, netStatusHandler);
          ns.addEventListener(AsyncErrorEvent.ASYNC_ERROR, ayncErrorHandler);
          ns.client = {onMetaData:ns_onMetaData};
          ns.bufferTime = 10;
          video.attachNetStream(ns);
          ns.play(videoURL);
          video.smoothing = true;
}
function ns_onMetaData(item:Object):void 
{
     video.width = item.width;
     video.height = item.height;
     trace("vid wid "+videoWidth);
     trace("vid hei "+videoHeight);
}
function securityErrorHandler(event:SecurityErrorEvent):void
{
          trace("securityErrorHandler: " + event);
}
function ayncErrorHandler(event: AsyncErrorEvent):void
{
}