Using LEADTOOLS DVR Components to Create a DirectShow Player Application

Perform the following steps to create and run a multimedia player DVR application using the LEADTOOLS Multimedia ConvertCtrl and PlayCtrl controls and the DVR components of the LEADTOOLS MPEG-2 Transport Module.

Start Visual Studio.
Choose File->New->Project... from the menu.
In the New Project dialog box, choose either "Visual C# Projects" or "VB Projects" in the Projects Type List, and choose "Windows Forms Application " in the Templates List.
Type the project name as "Multimedia Player DVR" in the Project Name field, and then choose OK. If desired, type a new location for your project or select a directory using the Browse button, and then click OK.
To add a reference to the Leadtools.Multimedia.dll right-click the "References" folder in the Solution Explorer window. Select "Add Reference..." from the context menu. In the "Add Reference" dialog box, select the ".NET" tab and select Leadtools.Multimedia.dll and click OK.
Next, add the reference to the LEADTOOLS COM Objects. Right-click the "References" folder, and select "Add Reference..." from the context menu. In the "Add Reference" dialog box, select the "COM" tab and select the following:
- LEAD MPEG-2 Transport Multiplexer Library
- LEAD MPEG2 Transport Demultiplexer Library
- LEAD DVR Sink Library
Note: The above COM objects must be registered; in case they were not; using regsvr32. For more information, refer to DirectShow Registry-free Activation. Next click OK to add the references.

Make sure Form1 is in design view. Go to the toolbox (View->Toolbox) and drag a ConvertCtrl control and a PlayCtrl control on the form. NOTE: If you do not have ConvertCtrl or PlayCtrl controls in your toolbox, select Tools->Choose Toolbox Items from the menu. Click Browse and then select Leadtools.Multimedia.dll from "<LEADTOOLS_INSTALLDIR>\Bin\Dotnet4\Win32" and then click Open and then click OK. After adding these controls to the form, set the following properties:

Property	Value
Name	_convertctrl
Anchor	Top, Left
BackColor	Black
Name	_playctrl
Anchor	Top, Bottom, Left, Right
AutoStart	False

Go to the toolbox (View->Toolbox) and drag a Text control on the form (below the convert control) and set the following properties:

Property	Value
Name	_txtSrcFile
Anchor	Bottom, Left
Locked	True

Go to the toolbox (View->Toolbox) and drag a Button control to the right of the text control and set the following properties:

Property	Value
Name	_buttonBrowse
Text	...
Anchor	Bottom, Left

Go to the toolbox (View->Toolbox) and drag a TrackBar control on the form (below the play control) and set the following properties:

Property	Value
Name	_track
Anchor	Bottom, Left, Right
Maximum	10000

Go to the toolbox (View->Toolbox) and drag six Button controls to the bottom of the form (first one below the convert control and the others below the play control) and set the following properties:

Property	Value
Name	_buttonStartStop
Text	Start
Anchor	Bottom, Left

Property	Value
Name	_buttonStop
Text	Stop
Anchor	Bottom, Right

Property	Value
Name	_buttonPlayMPEG2StreamWithDVRBuffer
Text	Play MPEG2 Stream With DVR Buffer
Anchor	Bottom, Right

Property	Value
Name	_buttonPlayDVRBufferFile
Text	Play DVR Buffer File
Anchor	Bottom, Right

Property	Value
Name	_buttonSetDVRBufferLocations
Text	Set DVR Buffer Locations
Anchor	Bottom, Right

Property	Value
Name	_buttonCopyBufferedDVRData
Text	Copy Buffered DVR Data
Anchor	Bottom, Right

Switch Form1 to code view (right-click Form1 in the Solution Explorer then choose View Code) and add the following lines to the beginning of the file:

vb 
      Imports Leadtools.Multimedia 
      Imports System.Runtime.InteropServices 
      Imports LMMpg2MxTLib 
      Imports LMMpgDmxTLib 
      Imports LMDVRSinkLib

      using Leadtools.Multimedia; 
      using System.Runtime.InteropServices; 
      using LMMpg2MxTLib; 
      using LMMpgDmxTLib; 
      using LMDVRSinkLib;

Declare the following private variable:

vb 
      Private Const SLIDER_MAX As Integer = 10000 
      Private _streaming As Boolean = False 
      Private _firstPTS As Double 
      Private _lastPTS As Double

      Private const int SLIDER_MAX = 10000; 
      Private bool _streaming = false; 
      Private double _firstPTS; 
      Private double _lastPTS;

Add an event handler to the _convertctrl Started event and add the following code:

vb 
      Private Sub _convertCtrl_Started(ByVal sender As Object, ByVal e As EventArgs) Handles _convertCtrl.Started 
         _streaming = True 
         _buttonBrowse.Enabled = False 
         _buttonPlayMPEG2StreamWithDVRBuffer.Enabled = True 
         _buttonSetDVRBufferLocations.Enabled = True 
         _buttonCopyBufferedDVRData.Enabled = True 
      End Sub

      void _convertCtrl_Started(object sender, EventArgs e) 
      { 
         _streaming = true; 
         _buttonBrowse.Enabled = false; 
         _buttonPlayMPEG2StreamWithDVRBuffer.Enabled = True; 
         _buttonSetDVRBufferLocations.Enabled = True; 
         _buttonCopyBufferedDVRData.Enabled = True; 
      }

Add an event handler to the _convertctrl Complete event and add the following code:

vb 
      Private Sub _convertCtrl_Complete(ByVal sender As Object, ByVal e As EventArgs) Handles _convertCtrl.Complete 
         If _streaming = True Then 
            _convertCtrl.StartConvert() 
         Else 
            _buttonStartStop.Text = "Start" 
            _buttonBrowse.Enabled = True 
            _buttonPlayMPEG2StreamWithDVRBuffer.Enabled = False 
            _buttonSetDVRBufferLocations.Enabled = False 
            _buttonCopyBufferedDVRData.Enabled = False 
         End If 
      End Sub

      void _convertCtrl_Complete(object sender, EventArgs e) 
      { 
         if (_streaming == true) 
            _convertCtrl.StartConvert(); 
         else 
         { 
            _buttonStartStop.Text = "Start"; 
            _buttonBrowse.Enabled = true; 
            _buttonPlayMPEG2StreamWithDVRBuffer.Enabled = False; 
            _buttonSetDVRBufferLocations.Enabled = False; 
            _buttonCopyBufferedDVRData.Enabled = False; 
         } 
      }

Add an event handler to the _playctrl TrackingPositionChanged event and add the following code:

vb 
      Private Sub _playctrl_TrackingPositionChanged(ByVal sender As Object, ByVal e As TrackingPositionChangedEventArgs) Handles _playctrl.TrackingPositionChanged 
         Dim demux As LMMpgDmxT = TryCast(_playctrl.GetSubObject(PlayObject.Splitter), LMMpgDmxT) 
         If Not demux Is Nothing Then 
            demux.RefreshPosition(0) 
            _firstPTS = demux.FirstStreamPTS 
            _lastPTS = demux.LastStreamPTS 
            _track.Value = PTSToSliderPosition(demux.CurrentStreamPTS) 
            Marshal.ReleaseComObject(demux) 
         End If 
      End Sub

      void _playctrl_TrackingPositionChanged(object sender, TrackingPositionChangedEventArgs e) 
      { 
         LMMpgDmxT demux = _playctrl.GetSubObject(PlayObject.Splitter) as LMMpgDmxT; 
         if (demux != null) 
         { 
            demux.RefreshPosition(0); 
            _firstPTS = demux.FirstStreamPTS; 
            _lastPTS = demux.LastStreamPTS; 
            _track.Value = PTSToSliderPosition(demux.CurrentStreamPTS); 
            Marshal.ReleaseComObject(demux); 
         } 
      }

Add an event handler to the _track Scroll event and add the following code:

vb 
      Private Sub _track_Scroll(ByVal sender As Object, ByVal e As EventArgs) Handles _track.Scroll 
         Dim demux As LMMpgDmxT = TryCast(_playctrl.GetSubObject(PlayObject.Splitter), LMMpgDmxT) 
         If Not demux Is Nothing Then 
            demux.RefreshPosition(0) 
            demux.CurrentStreamPTS = SliderPositionToPTS(_track.Value) 
            Marshal.ReleaseComObject(demux) 
         End If 
      End Sub

      private void _track_Scroll(object sender, EventArgs e) 
      { 
         LMMpgDmxT demux = _playctrl.GetSubObject(PlayObject.Splitter) as LMMpgDmxT; 
         if (demux != null) 
         { 
            demux.RefreshPosition(0); 
            demux.CurrentStreamPTS = SliderPositionToPTS(_track.Value); 
            Marshal.ReleaseComObject(demux); 
         } 
      }

Add the following helper methods for use by the _track control's scroll and _playctrl track positioning handlers:

vb 
      Private Function PTSToSliderPosition(ByVal curPTS As Double) As Integer 
         Dim retVal As Integer = 0 
         If curPTS <= _firstPTS Then 
            retVal = 0 
         ElseIf curPTS >= _lastPTS Then 
            retVal = SLIDER_MAX 
         Else 
            retVal = CInt(((curPTS - _firstPTS) * SLIDER_MAX) / (_lastPTS - _firstPTS) + 0.5) 
         End If 
         Return retVal 
      End Function 
      Private Function SliderPositionToPTS(ByVal nPos As Integer) As Double 
         Return _firstPTS + CDbl(nPos) * (_lastPTS - _firstPTS) / CDbl(SLIDER_MAX) 
      End Function

      private int PTSToSliderPosition(double curPTS) 
      { 
         int retVal = 0; 
         if (curPTS <= _firstPTS) 
            retVal = 0; 
         else if (curPTS >= _lastPTS) 
            retVal = SLIDER_MAX; 
         else 
            retVal = (int)(((curPTS - _firstPTS) * SLIDER_MAX) / (_lastPTS - _firstPTS) + 0.5); 
         return retVal; 
      } 
      private double SliderPositionToPTS(int nPos) 
      { 
         return _firstPTS + (double)nPos * (_lastPTS - _firstPTS) / (double)SLIDER_MAX; 
      }

Add an event handler to the _buttonBrowse Click event and add the following code:

vb 
      Private Sub _btnBrowse_Click(ByVal sender As Object, ByVal e As EventArgs) Handles _buttonBrowse.Click 
         Dim ofn As OpenFileDialog = New OpenFileDialog() 
         ofn.FileName = _txtSrcFile.Text 
         ofn.FilterIndex = 0 
         If _txtSrcFile.Text <> String.Empty Then 
            ofn.InitialDirectory = Path.GetDirectoryName(_txtSrcFile.Text) 
         Else 
            ofn.InitialDirectory = Directory.GetCurrentDirectory() 
         End If 
         ofn.Multiselect = False 
         ofn.Title = "Select Source Video" 
         ofn.CheckFileExists = True 
         ofn.Filter = "MPEG2 Video Files (*.mpg)|*.mpg |   All files (*.*)|*.*" 
         If ofn.ShowDialog() = DialogResult.OK Then 
            _txtSrcFile.Text = ofn.FileName 
         End If 
      End Sub

      private void _btnBrowse_Click(object sender, EventArgs e) 
      { 
         OpenFileDialog ofn = new OpenFileDialog(); 
         ofn.FileName = _txtSrcFile.Text; 
         ofn.FilterIndex = 0; 
                      
         if (_txtSrcFile.Text != string.Empty) 
            ofn.InitialDirectory = Path.GetDirectoryName(_txtSrcFile.Text); 
         else 
            ofn.InitialDirectory = Directory.GetCurrentDirectory(); 
         ofn.Multiselect = false; 
         ofn.Title = "Select Source Video"; 
         ofn.CheckFileExists = true; 
         ofn.Filter = "MPEG2 Video Files (*.mpg)|*.mpg |   All files (*.*)|*.*"; 
         if (ofn.ShowDialog() == DialogResult.OK) 
         { 
            _txtSrcFile.Text = ofn.FileName; 
         } 
      }

Add an event handler to the _buttonStartStop Click event and add the following code:

vb 
      Private Sub _btnStartStop_Click(ByVal sender As Object, ByVal e As EventArgs) Handles _buttonStartStop.Click 
         Dim srcFile As String = _txtSrcFile.Text 
         If _streaming = False Then 
            If srcFile <> String.Empty AndAlso File.Exists(srcFile) Then 
               _convertCtrl.SourceFile = srcFile 
               _convertCtrl.AllowedStreams = StreamFormatType.AudioVideoCC 
               _convertCtrl.PreferredMPEG2Splitter = Leadtools.Multimedia.Constants.Filter_MPEG2_Transport_Demux 
               _convertCtrl.TargetFormat = TargetFormatType.MPEG2Transport 
               _convertCtrl.Preview = True 
               _convertCtrl.TargetFile = "udp://127.0.0.1:9005" 
               Dim mux As LMMpg2MxT = TryCast(_convertCtrl.GetSubObject(ConvertObject.TargetFilter), LMMpg2MxT) 
               If Not mux Is Nothing Then 
                  mux.OutputType = CInt(LMMpg2MxTLib.Mpg2MxT_OutputType.Mpg2MxT_OutputType_Broadcast) 
                  mux.ResyncInterval = 10 
                  Marshal.ReleaseComObject(mux) 
               End If 
               Try 
                  _convertCtrl.StartConvert() 
                  _buttonStartStop.Text = "Stop" 
                  _buttonBrowse.Enabled = False 
               Catch e1 As Exception 
               End Try 
            End If 
         Else 
            If _streaming = True Then 
               _convertCtrl.StopConvert() 
               _buttonStartStop.Text = "Start" 
               _buttonBrowse.Enabled = True 
            End If 
         End If 
      End Sub

      private void _btnStartStop_Click(object sender, EventArgs e) 
      { 
         string srcFile = _txtSrcFile.Text; 
         if (_streaming == false) 
         { 
            if (srcFile != string.Empty && File.Exists(srcFile)) 
            { 
               _convertCtrl.SourceFile = srcFile; 
               _convertCtrl.AllowedStreams = StreamFormatType.AudioVideoCC; 
               _convertCtrl.PreferredMPEG2Splitter = Constants.Filter_MPEG2_Transport_Demux; 
               _convertCtrl.TargetFormat = TargetFormatType.MPEG2Transport; 
               _convertCtrl.Preview = true; 
               _convertCtrl.TargetFile = @"udp://127.0.0.1:9005"; 
               LMMpg2MxT mux = _convertCtrl.GetSubObject(ConvertObject.TargetFilter) as LMMpg2MxT; 
               if (mux != null) 
               { 
                  mux.OutputType = (int)LMMpg2MxTLib.Mpg2MxT_OutputType.Mpg2MxT_OutputType_Broadcast; 
                  mux.ResyncInterval = 10; 
                  Marshal.ReleaseComObject(mux); 
               } 
               try 
               { 
                  _convertCtrl.StartConvert(); 
                  _buttonStartStop.Text = "Stop"; 
                  _buttonBrowse.Enabled = false; 
               } 
               catch (Exception) { } 
            } 
         } 
         else 
         { 
            if (_streaming == true) 
            { 
               _convertCtrl.StopConvert(); 
               _buttonStartStop.Text = "Start"; 
               _buttonBrowse.Enabled = true; 
            } 
         } 
      }

Add an event handler to the _buttonStop Click event and code it as follows:

vb 
      Private Sub _buttonStop_Click(ByVal sender As Object, ByVal e As EventArgs) Handles _buttonStop.Click 
         If _playctrl.State = PlayState.Running Then 
            _playctrl.Stop() 
         End If 
      End Sub

      private void _buttonStop_Click(object sender, EventArgs e) 
      { 
         if (_playctrl.State == PlayState.Running) 
         { 
            _playctrl.Stop(); 
         } 
      }

Add an event handler to the _buttonPlayMPEG2StreamWithDVRBuffer Click event to play a UDP MPEG2 Stream with DVR Buffering and add the following code:

vb 
      Private Sub _buttonPlayMPEG2StreamWithDVRBuffer_Click(ByVal sender As Object, ByVal e As EventArgs) Handles _buttonPlayMPEG2StreamWithDVRBuffer.Click 
                      
         Try 
            ' Open the UDP Stream, but don't auto start  
            _playctrl.AutoStart = False 
            _playctrl.SourceFile = "udp://127.0.0.1:9005" 
            Dim DVRSink As LMDVRSinkLib.LMDVRSink 
            DVRSink = DirectCast(_playctrl.GetSubObject(PlayObject.SourceFilter), LMDVRSinkLib.LMDVRSink) 
           ' Tell the DVR Sink that settings are about to change 
           DVRSink.StartChangingAttributes() 
           ' Set only one DVR buffer folder  
           DVRSink.FolderCount = 1 
           ' Set the buffer base file name to 'Capture.LBL'  
           DVRSink.BaseName = "Capture.LBL" 
           ' Set the buffer folder location to 'C:\Temp\DVR'  
           DVRSink.FolderName(0) = ("C:\Temp\DVR") 
           ' Set the buffer folder to have 5 buffer data files, each at 100MB max size  
            DVRSink.SetBufferSize(0, 5, 102400000) 
           ' Commit the changed settings now  
           DVRSink.StopChangingAttributes(False) 
           ' Run the stream     
           _playctrl.Run() 
        Catch ex As Exception 
           MessageBox.Show(Me, ex.Message) 
        End Try 
                      
      End Sub

      private void _buttonPlayMPEG2StreamWithDVRBuffer_Click(object sender, EventArgs e) 
      { 
         try 
           { 
              // Open the UDP Stream, but don't auto start  
              _playctrl.AutoStart = false; 
              _playctrl.SourceFile = "udp://127.0.0.1:9005"; 
              LMDVRSinkLib.LMDVRSink DVRSink; 
              DVRSink = (LMDVRSinkLib.LMDVRSink)(_playctrl.GetSubObject(PlayObject.SourceFilter)); 
              // Tell the DVR Sink that settings are about to change 
              DVRSink.StartChangingAttributes(); 
              // Set only one DVR buffer folder  
              DVRSink.FolderCount = 1; 
              // Set the buffer base file name to 'Capture.LBL'  
              DVRSink.BaseName = "Capture.LBL"; 
              // Set the buffer folder location to 'C:\Temp\DVR'  
              DVRSink.set_FolderName(0, "C:\\Temp\\DVR"); 
              // Set the buffer folder to have 5 buffer data files, each at 100MB max size  
              DVRSink.SetBufferSize(0, 5, 102400000); 
              // Commit the changed settings now  
              DVRSink.StopChangingAttributes(false); 
              // Run the stream     
              _playctrl.Run(); 
           } 
           catch (Exception ex) 
           { 
              MessageBox.Show(this, ex.Message); 
           } 
      }

Add an event handler to the _buttonPlayDVRBufferFile Click event to play a DVR buffer file and add the following code:

vb 
      Private Sub _buttonPlayDVRBufferFile_Click(ByVal sender As Object, ByVal e As EventArgs) Handles _buttonPlayDVRBufferFile.Click 
                   
        Try 
           ' Set the source file on the player  
           _playctrl.SourceFile = "C:\Temp\DVR\Capture.LBL" 
                        
           ' Run the player     
           _playctrl.Run() 
        Catch ex As Exception 
           MessageBox.Show(Me, ex.Message) 
        End Try 
                     
      End Sub

      private void _buttonPlayDVRBufferFile_Click(object sender, EventArgs e) 
      { 
           try 
           { 
              // Set the source file on the player  
              _playctrl.SourceFile = "C:\\Temp\\DVR\\Capture.LBL"; 
                           
              // Run the stream     
              _playctrl.Run(); 
           } 
           catch (Exception ex) 
           { 
              MessageBox.Show(this, ex.Message); 
           } 
      }

Add an event handler to the _buttonSetDVRBufferLocations Click event to Set DVR Buffer Locations on More Than One Physical Disk and code it as follows:

vb 
      Private Sub _buttonSetDVRBufferLocations_Click(ByVal sender As Object, ByVal e As EventArgs) Handles _buttonSetDVRBufferLocations.Click 
                   
        Try 
                     
           ' Open the UDP Stream, but don't auto start 
           _playctrl.AutoStart = false 
           _playctrl.SourceFile = "udp://127.0.0.1:9005" 
                        
           Dim DVRSink As LMDVRSinkLib.LMDVRSink 
           DVRSink = DirectCast(_playctrl.GetSubObject(PlayObject.SourceFilter), LMDVRSinkLib.LMDVRSink) 
           ' Tell sink we are starting to change settings 
           DVRSink.StartChangingAttributes() 
           ' Set Two buffer locations  
           DVRSink.FolderCount = 2 
           ' Set base file name  
           DVRSink.BaseName = "Capture.LBL" 
           ' Set buffer folder 1 location 
           DVRSink.FolderName(0) = "C:\Temp\DVR" 
           ' Set buffer folder 1 to have 2 buffer data files, each at 16MB max file size 
           DVRSink.SetBufferSize(0, 2, 16 * 1024000) 
           ' Set buffer folder 2 location 
           DVRSink.FolderName(1) = "D:\Temp\DVR" 
           ' Set buffer folder 2 to have 4 buffer data files, each at 8MB max file size 
           DVRSink.SetBufferSize(1, 4, 8192000) 
           ' Tell sink to apply the changes  
           DVRSink.StopChangingAttributes(False) 
                        
           ' Run the player     
           _playctrl.Run() 
        Catch ex As Exception 
           MessageBox.Show(Me, ex.Message) 
        End Try 
      End Sub

      private void _buttonSetDVRBufferLocations_Click(object sender, EventArgs e) 
      { 
           try 
           { 
              // Open the UDP Stream, but don't auto start 
              _playctrl.AutoStart = false; 
              _playctrl.SourceFile = "udp://127.0.0.1:9005"; 
                           
              LMDVRSinkLib.LMDVRSink DVRSink; 
              DVRSink = (LMDVRSinkLib.LMDVRSink)(_playctrl.GetSubObject(PlayObject.SourceFilter)); 
              // Tell sink we are starting to change settings 
              DVRSink.StartChangingAttributes(); 
              // Set Two buffer locations  
              DVRSink.FolderCount = 2; 
              // Set base file name  
              DVRSink.BaseName = "Capture.LBL"; 
              // Set buffer folder 1 location 
              DVRSink.set_FolderName(0, "C:\\Temp\\DVR"); 
              // Set buffer folder 1 to have 2 buffer data files, each at 16MB max file size 
              DVRSink.SetBufferSize(0, 2, 16 * 1024000); 
              // Set buffer folder 2 location 
              DVRSink.set_FolderName(1, "D:\\Temp\\DVR"); 
              // Set buffer folder 2 to have 4 buffer data files, each at 8MB max file size 
              DVRSink.SetBufferSize(1, 4, 8192000); 
              // Tell sink to apply the changes  
              DVRSink.StopChangingAttributes(false); 
                              
              // Run the player     
              _playctrl.Run(); 
           } 
           catch (Exception ex) 
           { 
              MessageBox.Show(this, ex.Message); 
           } 
      }

Add an event handler to the _buttonCopyBufferedDVRData Click event to play a DVR buffer file and add the following code:

vb 
      Private Sub _buttonCopyBufferedDVRData_Click(ByVal sender As Object, ByVal e As EventArgs) Handles _buttonCopyBufferedDVRData.Click 
                   
      Try 
           Dim first As Double 
           Dim last As Double 
           Dim total As Double 
           _playctrl.AutoStart = False 
           _playctrl.SourceFile = "udp://127.0.0.1:9005" 
           Dim DVRSink As LMDVRSinkLib.LMDVRSink 
           DVRSink = DirectCast(_playctrl.GetSubObject(PlayObject.SourceFilter), LMDVRSinkLib.LMDVRSink) 
           ' Get available range to copy  
           DVRSink.GetAvailabilityInfo(first, last, total) 
           ' Copy the data to the new file  
           DVRSink.CopyBufferToFile("C:\Temp\DVR\Copied_Capture.mpg", first, last) 
                       Catch ex As Exception 
           MessageBox.Show(Me, ex.Message) 
                       End Try 
                     
      End Sub

      private void _buttonCopyBufferedDVRData_Click(object sender, EventArgs e) 
      { 
           try 
           { 
              double first; 
              double last; 
              double total; 
              // Open the UDP Stream, but don't auto start  
              _playctrl.AutoStart = false; 
              _playctrl.SourceFile = "udp://127.0.0.1:9005"; 
              LMDVRSinkLib.LMDVRSink DVRSink; 
              DVRSink = (LMDVRSinkLib.LMDVRSink)(_playctrl.GetSubObject(PlayObject.SourceFilter)); 
              // Get available range to copy  
              DVRSink.GetAvailabilityInfo(out first, out last, out total); 
              // Copy the data to the new file  
              DVRSink.CopyBufferToFile("C:\\Temp\\DVR\\Copied_Capture.mpg", first, last); 
           } 
           catch (Exception ex) 
           { 
              MessageBox.Show(this, ex.Message); 
           } 
      }

Build, and Run the program to test it. Click the [...] browse button to locate a video file for the convert / streaming output. Then click the Start button to begin streaming. Click the Play MPEG2 Stream With DVR Buffer button to test playing a UDP MPEG2 Stream with DVR Buffering. Click the Play DVR Buffer button to test playing a DVR buffer file. Click the Set DVR Buffer Locations button to test Setting DVR Buffer Locations on More Than One Physical Disk and play a UDP MPEG2 Stream with DVR Buffering. Click the Copy Buffered DVR Data button to test copy buffered DVR data to a new file. Finally, drag the track bar control to reposition the stream playback.