Silverlight与WCF之间的通信(6)silverlight+wcf+tcp视频通信[1]单工模式

其实严格来讲，这个实现并非真正意义上的视频通信，既不是P2P的，也没有很高的性能，因为基本上是两个客户端同时往服务器上传递视频信息，然后由服务器进行中转到对方。

重点在于两点

• IIS根目录下放clientaccesspolicy.xml文件
• 注意服务中定义数据量大小2147483646，否则有可能传递不了

这边是单向的客户端定时向服务器传递带聊天标识的数据流： 

代码

[DataContract] 
     public   class  UserVideo 
    { 
        [DataMember] 
         public   string  UserName {  get ;  set ; } 
        [DataMember] 
         public   string  PartnerName {  set ;  get ; } 
        [DataMember] 
         public   byte [] VideoByte {  set ;  get ; } 
    }  

服务契约只有两个，一个是用来存储视频流，一个是用来提供视频流的 

代码

[ServiceContract] 
     public   interface  IChatService 
    { 
        [OperationContract] 
         void  SendVideo(UserVideo userVideo); 

        [OperationContract] 
        List < UserVideo >  GetVideos( string  userName, string  partnerName); 
    }

 实现也很简单就是往一个静态的List中添加对象 

代码

public   class  ChatService : IChatService 
    { 
         private   static  List < UserVideo >  listVideos  =   new  List < UserVideo > ();         

         public   void  SendVideo(UserVideo userVideo) 
        { 
            listVideos.Add(userVideo); 
        } 

         public  List < UserVideo >  GetVideos( string  userName, string  partnerName) 
        { 
            var list  =  listVideos.Where(m  =>  m.UserName  ==  userName  &&  m.PartnerName  ==  partnerName).ToList(); 
            listVideos.RemoveAll(m  =>  m.PartnerName  ==  partnerName  &&  m.UserName  ==  userName); 
             return  list; 
        } 
    }

 

接下来是host方法 

代码

public   class  MyHost 
    { 
         static  ServiceHost host  =   null ; 
         public   static   void  open() 
        { 
            host  =   new  ServiceHost( typeof (ChatService)); 
            host.open(); 
        } 
         public   static   void  Close() 
        { 
             if  (host  !=   null   &&  host.State  ==  CommunicationState.Opened) 
            { 
                host.Close(); 
            } 
            host  =   null ; 
        } 
    }

 最后是启动服务进行监听 

代码

public   class  Program 
    { 
         static   void  Main( string [] args) 
        { 
            MyHost.open(); 
            System.Console.WriteLine( " 服务已经启动...   敲任意键停止服务 " ); 
            System.Console.ReadLine(); 
            MyHost.Close(); 
        } 
    }

 
客户端方法：

开始视频播放

this .btnStartVideo.Click  +=  (o, ev)  =>  
            { 
                 if  (source  !=   null ) 
                { 
                    source.Stop(); 
                    source.VideoCaptureDevice  =  CaptureDeviceConfiguration.GetDefaultVideoCaptureDevice(); 
                    VideoBrush vBrush  =   new  VideoBrush(); 
                    vBrush.SetSource(source); 
                     this .rectangleUser.Fill  =  vBrush; 
                     if  (CaptureDeviceConfiguration.AllowedDeviceAccess  ||  CaptureDeviceConfiguration.RequestDeviceAccess()) 
                    { 
                        source.Start(); 
                    } 
                } 
            };

 

向服务器发送数据流

this .btnSendVideo.Click  +=  (o, ev)  =>  
            { 
                timerForSend  =   new  System.Windows.Threading.dispatcherTimer(); 
                timerForSend.Interval  =   new  TimeSpan( 0 ,  0 ,  150 ); 
                timerForSend.Tick  +=  (o1, e1)  =>  { 
                    proxy  =   new  ChatServiceClient(); 
                    WriteableBitmap bmp  =   new  WriteableBitmap( this .rectangleUser,  null ); 
                    MemoryStream ms  =   new  MemoryStream(); 
                    EncodeJpeg(bmp, ms); 
                    UserVideo userVideo  =   new  UserVideo(); 
                    userVideo.PartnerName  =   this .Partner; 
                    userVideo.UserName  =   this .User; 
                    userVideo.VideoByte  =  ms.GetBuffer(); 
                    proxy.SendVideoCompleted  +=  (o2, e2)  =>  { }; 
                    proxy.SendVideoAsync(userVideo); 
                }; 
                timerForSend.Start(); 
            };

 

从服务期上取得数据流 

代码

void  ReceiveVideo() 
        { 
            timerForReceive  =   new  System.Windows.Threading.dispatcherTimer(); 
            timerForReceive.Interval  =   new  TimeSpan( 0 ,  100 ); 
            timerForReceive.Tick  +=  (o, e)  =>  { 
                proxy  =   new  ChatServiceClient(); 
                proxy.GetVideosCompleted  +=  (se, ev)  =>  
                { 
                     if  (ev.Error  ==   null ) 
                    { 
                         foreach  (ChatService.UserVideo video  in  ev.Result) 
                        { 
                             this .imagePartner.dispatcher.BeginInvoke(()  =>  { 
                                MemoryStream ms  =   new  MemoryStream(video.VideoByte); 
                                BitmapImage bitmap  =   new  BitmapImage(); 
                                bitmap.SetSource(ms); 
                                imagePartner.source  =  bitmap; 
                                ms.Close(); 
                            }); 
                        } 
                    } 
                }; 
                proxy.GetVideosAsync(User, Partner); 
            }; 
            timerForReceive.Start(); 
        }          

 

  

单工模式的缺点显而易见，请求--》答复比较耗时，我们下一步将会改造成双工模式的TCP通信。