LiveSource Property

Summary

Gets or sets a value that indicates whether the media source is treated as a live source.

Syntax
C#
VB
C++
[DispIdAttribute(3)] 
bool LiveSource {get; set;} 
  
<DispIdAttribute(3)> 
Property LiveSource As Boolean 
[DispIdAttribute(3)] 
property bool LiveSource { 
   bool get(); 
   void set (    bool ); 
} 

Property Value

true if the source is treated as a live source; otherwise it is false if the source is not live.

Remarks

If the media source is a live source, dropping samples is allowed if the output is lagging behind the source.

If the media source is NOT live, the multiplexer will buffer more samples to keep up with the source.

This uses the MaxQueueDuration value to determine when to drop samples.

In a live capture situation the multiplexer will drop samples in attempt to prevent the video stream from halting before the MaxQueueDuration is reached.

The Leadtools Multiplexer will start dropping samples at 2/3 of the MaxQueueDuration.

Example
C#
VB
using Leadtools; 
using Leadtools.Multimedia; 
using LeadtoolsMultimediaExamples.Fixtures; 
 
public bool _result = false; 
public CaptureCtrlForm _form = new CaptureCtrlForm(); 
public CaptureCtrl _captureCtrl; 
 
const int MaxBitRate = 128; 
const int TestBitRate = MaxBitRate + 1; 
 
public void NetworkMultiplexerExample() 
{ 
   // reference the capture control 
   _captureCtrl = _form.CaptureCtrl; 
 
   // output file 
   string outFile = @"ltsf://127.0.0.1:27015"; 
 
   try 
   { 
      // try to find a USB camera 
      if (_captureCtrl.VideoDevices["Logitech"] == null) 
         throw new Exception("No Logitech video device available"); 
 
      _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 = outFile; 
 
      if (_captureCtrl.IsModeAvailable(CaptureMode.Video)) 
      { 
         // just 10 seconds of capture time 
         _captureCtrl.TimeLimit = 10; 
         _captureCtrl.UseTimeLimit = true; 
 
         // ready the capture graph in order to get the LNMetMux instance 
         _captureCtrl.ReadyCapture(CaptureMode.Video); 
 
         // get the network multiplexer reference 
         LMNetMux pMux = _captureCtrl.GetSubObject(CaptureObject.TargetFilter) as LMNetMux; 
 
         if (pMux != null) 
         { 
            // set live source (dropping samples is allowed if the sink is not sending fast enough to keep up) 
            pMux.LiveSource = true; 
 
            // atleast 10 seconds for the netmux sample queue 
            if (pMux.MaxQueueDuration < 10) 
               pMux.MaxQueueDuration = 10; 
 
            // 128 kbps max 
            pMux.BitRateLimit = MaxBitRate * 1024; 
 
            // set the result to what we expect 
            _result = true; 
         } 
 
         // 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. 
         while (_captureCtrl.State == CaptureState.Running) 
         { 
            if (pMux != null) 
            { 
               // confirm that the actual bitrate does not exceed our max specified above 
               _result &= (pMux.BitRate / 1024 < TestBitRate); 
            } 
            Application.DoEvents(); 
         } 
 
         // release the mux since its a COM object 
         if (pMux != null) 
            Marshal.ReleaseComObject(pMux); 
      } 
   } 
   catch (Exception) 
   { 
      _result = false; 
   } 
} 
Imports Leadtools 
Imports Leadtools.Multimedia 
Imports LeadtoolsMultimediaExamples.Fixtures 
 
Public _result As Boolean = False 
Public _form As CaptureCtrlForm = New CaptureCtrlForm() 
Public _captureCtrl As CaptureCtrl 
 
Private Const MaxBitRate As Integer = 128 
Private Const TestBitRate As Integer = MaxBitRate + 1 
 
Public Sub NetworkMultiplexerExample() 
   ' reference the capture control 
   _captureCtrl = _form.CaptureCtrl 
 
   ' output file 
   Dim outFile As String = "ltsf://127.0.0.1:27015" 
 
   Try 
      ' try to find a USB 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 = outFile 
 
      If _captureCtrl.IsModeAvailable(CaptureMode.Video) Then 
         ' just 10 seconds of capture time 
         _captureCtrl.TimeLimit = 10 
         _captureCtrl.UseTimeLimit = True 
 
         ' ready the capture graph in order to get the LNMetMux instance 
         _captureCtrl.ReadyCapture(CaptureMode.Video) 
 
         ' get the network multiplexer reference 
         Dim pMux As LMNetMux = TryCast(_captureCtrl.GetSubObject(CaptureObject.TargetFilter), LMNetMux) 
 
         If Not pMux Is Nothing Then 
            ' set live source (dropping samples is allowed if the sink is not sending fast enough to keep up) 
            pMux.LiveSource = True 
 
            ' atleast 10 seconds for the netmux sample queue 
            If pMux.MaxQueueDuration < 10 Then 
               pMux.MaxQueueDuration = 10 
            End If 
 
            ' 128 kbps max 
            pMux.BitRateLimit = MaxBitRate * 1024 
 
            ' set the result to what we expect 
            _result = 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 
            If Not pMux Is Nothing Then 
               ' confirm that the actual bitrate does not exceed our max specified above 
               _result = _result And (pMux.BitRate / 1024 < TestBitRate) 
            End If 
            Application.DoEvents() 
         Loop 
 
         ' release the mux since its a COM object 
         If Not pMux Is Nothing Then 
            Marshal.ReleaseComObject(pMux) 
         End If 
      End If 
   Catch e1 As Exception 
      _result = False 
   End Try 
End Sub 

Requirements

Target Platforms

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