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Channel Property
See Also 
Leadtools.Multimedia Namespace > TVTuner Class : Channel Property



Gets the current channel.

Syntax

Visual Basic (Declaration) 
Public ReadOnly Property Channel As Integer
Visual Basic (Usage)Copy Code
Dim instance As TVTuner
Dim value As Integer
 
value = instance.Channel
C# 
public int Channel {get;}
C++/CLI 
public:
property int Channel {
   int get();
}

Property Value

A value which represents the current channel

Example

Visual BasicCopy Code
Public _result As Boolean = False
      Public _form As CaptureCtrlForm = New CaptureCtrlForm()
      Public Sub AnalogTVTunerExample()
         ' reference the forms capture control and tv tuner
         Dim capturectrl As CaptureCtrl = _form.CaptureCtrl

         Dim outFile As String = Path.Combine(LEAD_VARS.MediaDir, "TVTuner_AnalogTVTunerExample.avi")
         Dim testChan As Integer = 6
         Dim channel As Integer

         Try
            ' select the first device with analog in it's name
            ' Replace "Analog" with your video capture device name
            If capturectrl.VideoDevices("Analog") Is Nothing Then
               Throw New Exception("No Analog video devices available!")
            End If

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

            ' use the video capture device's audio
            capturectrl.UseVideoDeviceAudio = True

            ' get the TV Tuner device
            Dim tvtuner As TVTuner = capturectrl.TVTuner

            ' Check if TV tuner is valid
            If Not tvtuner Is Nothing Then
               ' set the input type to cable and set the channel
               tvtuner.SetInputType(0, TunerInputType.Cable)
               tvtuner.SetChannel(testChan, -1, -1)

               ' get the Video and Audio frequency
               Dim vidFreq As Integer = tvtuner.VideoFrequency
               Dim audFreq As Integer = tvtuner.AudioFrequency
            End If

            ' set the output file
            capturectrl.TargetFile = outFile

            ' set the video and audio compressors
            capturectrl.VideoCompressors.Mpeg2.Selected = True
            capturectrl.AudioCompressors.AC3.Selected = True

            ' check if we have can capture video
            If capturectrl.IsModeAvailable(CaptureMode.VideoAndAudio) Then
               ' set the target format
               capturectrl.TargetFormat = TargetFormatType.AVI

               capturectrl.TimeLimit = 10 ' just 10 seconds of capture time
               capturectrl.UseTimeLimit = True

               ' select the video subtype
               capturectrl.VideoCaptureSubTypes(Leadtools.Multimedia.Constants.MEDIASUBTYPE_YUY2).Selected = True

               ' start the capture
               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

               ' if TV tuner is valid
               If Not tvtuner Is Nothing Then
                  ' check the channel
                  channel = tvtuner.Channel

                  ' and set the result to what we expect
                  _result = (channel = testChan)
               End If
            End If
         Catch e1 As Exception
            _result = False
         End Try
      End Sub

Public NotInheritable Class LEAD_VARS
   Public Const MediaDir As String = "C:\Program Files (x86)\LEAD Technologies\LEADTOOLS 17\Media"
End Class
C#Copy Code
public bool _result = false;
      public CaptureCtrlForm _form = new CaptureCtrlForm();
      public void AnalogTVTunerExample()
      {
         // reference the forms capture control and tv tuner
         CaptureCtrl capturectrl = _form.CaptureCtrl;

         string outFile =Path.Combine(LEAD_VARS.MediaDir,"TVTuner_AnalogTVTunerExample.avi");
         int testChan = 6;
         int channel;

         try
         {
            // select the first device with analog in it's name
            // Replace "Analog" with your video capture device name
            if (capturectrl.VideoDevices["Analog"] == null)
               throw new Exception("No Analog video devices available!");

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

            // use the video capture device's audio
            capturectrl.UseVideoDeviceAudio = true;

            // get the TV Tuner device
            TVTuner tvtuner = capturectrl.TVTuner;

            // Check if TV tuner is valid
            if (tvtuner != null)
            {
               // set the input type to cable and set the channel
               tvtuner.SetInputType(0, TunerInputType.Cable);
               tvtuner.SetChannel(testChan, -1, -1);

               // get the Video and Audio frequency
               int vidFreq = tvtuner.VideoFrequency;
               int audFreq = tvtuner.AudioFrequency;
            }

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

            // set the video and audio compressors
            capturectrl.VideoCompressors.Mpeg2.Selected = true;
            capturectrl.AudioCompressors.AC3.Selected = true;

            // check if we have can capture video
            if (capturectrl.IsModeAvailable(CaptureMode.VideoAndAudio))
            {
               // set the target format
               capturectrl.TargetFormat = TargetFormatType.AVI;

               capturectrl.TimeLimit = 10;     // just 10 seconds of capture time
               capturectrl.UseTimeLimit = true;

               // select the video subtype
               capturectrl.VideoCaptureSubTypes[Constants.MEDIASUBTYPE_YUY2].Selected = true;

               // start the capture
               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();

               // if TV tuner is valid
               if (tvtuner != null)
               {
                  // check the channel
                  channel = tvtuner.Channel;

                  // and set the result to what we expect
                  _result = (channel == testChan);
               }
            }
         }
         catch (Exception)
         {
            _result = false;
         }
      }

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

Remarks

Use the SetChannel method to set the TV channel.

For a list of frequencies for channels, see the Microsoft documentation on International Analog TV Tuning.

For more detailed information, refer to the Microsoft documentation for IAMTVTuner.get_Channel.

Requirements

Target Platforms: Microsoft .NET Framework 2.0, Windows 2000, Windows XP, Windows Server 2003 family, Windows Server 2008 family, Windows Vista, Windows 7

See Also