UseVideoDeviceAudio Property

Gets or sets the option to use the audio source in the current video device.

Syntax

Visual Basic
C#
C++/CLI

'Declaration
 
Public Overridable Property UseVideoDeviceAudio As Boolean

'Usage
 
Dim instance As CaptureCtrl
Dim value As Boolean
 
instance.UseVideoDeviceAudio = value
 
value = instance.UseVideoDeviceAudio

public virtual bool UseVideoDeviceAudio {get; set;}

public:
virtual property bool UseVideoDeviceAudio {
   bool get();
   void set (    bool value);
}

Property Value

true if the audio source in the video device is used; false, otherwise.

Remarks

The default value for this property is True. It specifies whether the CaptureCtrl object will use the audio from the video device, if no audio device has been explicitly selected. For instance, DV devices contain both audio and video. Normally, if you select a DV device with no audio device, the DV device's audio stream will be used. However, if you set this property to False, then no audio stream will be rendered. This helps build a slightly more efficient graph when processing video only from DV devices.

Example

Visual Basic
C#
WinRT C#
WinRT JavaScript
Silverlight C#
Silverlight VB

Copy Code

Imports Leadtools
Imports Leadtools.Multimedia
Imports LeadtoolsMultimediaExamples.Fixtures

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 18\Media"
End Class

using Leadtools;
using Leadtools.Multimedia;
using LeadtoolsMultimediaExamples.Fixtures;

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 whether the 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 whether we 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 18\Media";
}

Requirements

Target Platforms

Reference

CaptureCtrl Class
CaptureCtrl Members