WriteMessage Method

Imports Leadtools
Imports Leadtools.Multimedia
Imports LeadtoolsMultimediaExamples.Fixtures

Public _result As Boolean = False
Public _serverAndClient As CaptureAndPlayCtrlForm = New CaptureAndPlayCtrlForm()
Private _msgSent As Boolean = False
Private _captureCtrl As CaptureCtrl
Private _playCtrl As PlayCtrl
Private _pMux As LMNetMux
Private _pDemux As LMNetDmx

Private Const _networkUrl As String = "ltsf://127.0.0.1:27015" ' network stream url
Private Const TestMessage As String = "LEAD NETWORK"

Public Sub WriteMessageExample()
   ' reference the capture control
   _captureCtrl = _serverAndClient.CaptureCtrl

   ' reference the play control
   _playCtrl = _serverAndClient.PlayCtrl

   Try
      ' try to find a video camera
      If _captureCtrl.VideoDevices("Logitech") Is Nothing Then
         Throw New Exception("No Logitech video device available")
      End If

      _captureCtrl.VideoDevices("Logitech").Selected = True

      ' select a video compressor
      _captureCtrl.VideoCompressors.Mpeg4.Selected = True

      ' set the target output file
      _captureCtrl.TargetFormat = TargetFormatType.NET
      _captureCtrl.TargetFile = _networkUrl

      If _captureCtrl.IsModeAvailable(CaptureMode.Video) Then
         ' just 10 seconds of capture time
         _captureCtrl.TimeLimit = 10
         _captureCtrl.UseTimeLimit = True

         _captureCtrl.Preview = True

         ' subscribe to the started and progress events for this example
         ' we will connect a client after the capture starts
         ' and send a test message after 5 seconds.
         AddHandler _captureCtrl.Started, AddressOf CaptureCtrl_Started
         AddHandler _captureCtrl.Progress, AddressOf CaptureCtrl_Progress

         ' ready the capture graph in order to get the LNMetMux instance
         _captureCtrl.ReadyCapture(CaptureMode.Video)

         ' get the network multiplexer reference
         _pMux = TryCast(_captureCtrl.GetSubObject(CaptureObject.TargetFilter), LMNetMux)

         If Not _pMux Is Nothing Then
            ' set some mux settings
            _pMux.LiveSource = True
         End If

         ' start capture
         _captureCtrl.StartCapture(CaptureMode.Video)

         ' we'll loop on the state and pump messages for this example.
         ' but you should not need to if running from a Windows Forms application.
         Do While _captureCtrl.State = CaptureState.Running OrElse _playCtrl.State = PlayState.Running
            Application.DoEvents()
         Loop

         ' release the mux and demux COM objects
         If Not _pMux Is Nothing Then
            Marshal.ReleaseComObject(_pMux)
         End If

         If Not _pDemux Is Nothing Then
            Marshal.ReleaseComObject(_pDemux)
         End If
      End If
   Catch e1 As Exception
      _result = False
   End Try
End Sub

Private Sub CaptureCtrl_Progress(ByVal sender As Object, ByVal e As ProgressEventArgs)
   ' for this test we will send a message after 
   ' 5 secs of capture time
   If e.time > 5000 AndAlso (Not _msgSent) Then
      _pMux.WriteMessage(TestMessage)
      Console.WriteLine("Server sent message")
      _msgSent = True
   End If
End Sub

Private Sub CaptureCtrl_Started(ByVal sender As Object, ByVal e As EventArgs)
   StartClient()
End Sub

Private Sub StartClient()
   _playCtrl.SourceFile = _networkUrl
   _pDemux = TryCast(_playCtrl.GetSubObject(PlayObject.Splitter), LMNetDmx)

   _serverAndClient.TestTimer.Interval = 100
   AddHandler _serverAndClient.TestTimer.Tick, AddressOf PlayTimer_Tick
   _serverAndClient.TestTimer.Start()
End Sub

Private Sub PlayTimer_Tick(ByVal sender As Object, ByVal e As EventArgs)
   _serverAndClient.TestTimer.Enabled = False
   If Not _pDemux Is Nothing Then
      Dim msg As String = _pDemux.ReadMessage()

      ' set the result to what we expect
      If msg = TestMessage Then
         _result = True
         Console.WriteLine("Client received message")
      End If
   End If
   _serverAndClient.TestTimer.Enabled = True
End Sub