Public Enum CapturePreviewTap 
   Inherits System.Enum
   Implements IComparable, IConvertible, IFormattable 

Dim instance As CapturePreviewTap

public enum CapturePreviewTap : System.Enum, IComparable, IConvertible, IFormattable  

public enum class CapturePreviewTap : public System.Enum, IComparable, IConvertible, IFormattable  

Public _result As Boolean = False
      Public _form As CaptureCtrlForm = New CaptureCtrlForm()
      Public Sub CapturePreviewExample()
         ' reference the capture control
         Dim capturectrl As CaptureCtrl = _form.CaptureCtrl

         ' output file for processor settings
         Dim outFile As String = Path.Combine(LEAD_VARS.MediaDir, "CaptureCtrl_IsModeAvailableExample.avi")

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

            capturectrl.VideoDevices("USB").Selected = True

            ' try to find a USB audio device
            If capturectrl.AudioDevices("USB") Is Nothing Then
               Throw New Exception("No USB audio device available")
            End If

            capturectrl.AudioDevices("USB").Selected = True

            ' set MPEG2 as the video compressor
            capturectrl.VideoCompressors.Mpeg2.Selected = True

            ' set AC3 as the audio compressor
            capturectrl.AudioCompressors.AC3.Selected = True

            ' set the target output file
            capturectrl.TargetFile = outFile

            ' set the target output format
            capturectrl.TargetFormat = TargetFormatType.AVI

            ' check if we have can capture video
            If capturectrl.IsModeAvailable(CaptureMode.VideoAndAudio) Then
               capturectrl.FrameRate = 5 ' 5 frames per second
               capturectrl.UseFrameRate = True
               capturectrl.TimeLimit = 10 ' just 10 seconds of capture time
               capturectrl.UseTimeLimit = True

               ' check to see if we can preview compressed output
               If capturectrl.IsPreviewTapSupported(CapturePreview.Video, CapturePreviewTap.Compressor) Then
                  ' enable preview
                  capturectrl.Preview = True

                  ' enable preview video
                  capturectrl.PreviewSource = CapturePreview.Video

                  ' set the preview tap location
                  capturectrl.PreviewTap = CapturePreviewTap.Compressor
               End If

               ' subscribte to the compete event
               AddHandler capturectrl.Complete, AddressOf CaptureCtrl_Complete

               ' start the capture process
               capturectrl.StartCapture(CaptureMode.VideoAndAudio)

               ' 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
                  Application.DoEvents()
               Loop
            End If
         Catch e1 As Exception
            _result = False
         End Try
      End Sub

      Public Sub CaptureCtrl_Complete(ByVal sender As Object, ByVal e As EventArgs)
         ' set result
         _result = True
      End Sub

Public NotInheritable Class LEAD_VARS
   Public Const MediaDir As String = "C:\Program Files (x86)\LEAD Technologies\LEADTOOLS 17\Media"
End Class

public bool _result = false;
      public CaptureCtrlForm _form = new CaptureCtrlForm();
      public void CapturePreviewExample()
      {
         // reference the capture control
         CaptureCtrl capturectrl = _form.CaptureCtrl;

         // output file for processor settings
         string outFile = Path.Combine(LEAD_VARS.MediaDir,"CaptureCtrl_IsModeAvailableExample.avi");

         try
         {
            // try to find a USB camera
            if (capturectrl.VideoDevices["USB"] == null)
               throw new Exception("No USB video device available");

            capturectrl.VideoDevices["USB"].Selected = true;

            // try to find a USB audio device
            if (capturectrl.AudioDevices["USB"] == null)
               throw new Exception("No USB audio device available");

            capturectrl.AudioDevices["USB"].Selected = true;

            // set MPEG2 as the video compressor
            capturectrl.VideoCompressors.Mpeg2.Selected = true;

            // set AC3 as the audio compressor
            capturectrl.AudioCompressors.AC3.Selected = true;

            // set the target output file
            capturectrl.TargetFile = outFile;

            // set the target output format
            capturectrl.TargetFormat = TargetFormatType.AVI;

            // check if we have can capture video
            if (capturectrl.IsModeAvailable(CaptureMode.VideoAndAudio))
            {
               capturectrl.FrameRate = 5;       // 5 frames per second 
               capturectrl.UseFrameRate = true;
               capturectrl.TimeLimit = 10;      // just 10 seconds of capture time
               capturectrl.UseTimeLimit = true;

               // check to see if we can preview compressed output
               if (capturectrl.IsPreviewTapSupported(CapturePreview.Video, CapturePreviewTap.Compressor))
               {
                  // enable preview
                  capturectrl.Preview = true;

                  // enable preview video
                  capturectrl.PreviewSource = CapturePreview.Video;

                  // set the preview tap location
                  capturectrl.PreviewTap = CapturePreviewTap.Compressor;
               }

               // subscribte to the compete event
               capturectrl.Complete += new EventHandler(CaptureCtrl_Complete);

               // start the capture process
               capturectrl.StartCapture(CaptureMode.VideoAndAudio);

               // 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)
                  Application.DoEvents();
            }
         }
         catch (Exception)
         {
            _result = false;
         }
      }

      public void CaptureCtrl_Complete(object sender, EventArgs e)
      {
         // set result
         _result = true;
      }

static class LEAD_VARS
{
   public const string MediaDir = @"C:\Program Files (x86)\LEAD Technologies\LEADTOOLS 17\Media";
}