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ClosedCaptioning Property

Summary

Gets a value that indicates whether closed captioning is enabled.

Syntax

C++

public virtual bool ClosedCaptioning { get; set; }

Public Overridable Property ClosedCaptioning As Boolean

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

Property Value

true if Closed Captioning is enabled; false, otherwise.

Remarks

Closed captioning is the text transcription of audio overlaid on the video frame. Assignment can raise an error exception. For more information, refer to the Error Codes.

Example

using Leadtools; 
using Leadtools.Multimedia; 
using LeadtoolsMultimediaExamples.Fixtures; 
 
public bool _result = false; 
public CaptureCtrlForm _form = new CaptureCtrlForm(); 
public CaptureCtrl _capturectrl; 
 
public void ClosedCaptioningExample() 
{ 
   // reference the capture control 
   _capturectrl = _form.CaptureCtrl; 
 
   // output file names 
   string outFile = Path.Combine(LEAD_VARS.MediaDir, "CaptureCtrl_ClosedCaptioningExample_DVD"); 
 
   try 
   { 
      // try to find a Digital tuner, use your device name here 
      if (_capturectrl.VideoDevices["Analog"] == null) 
         throw new Exception("No Analog video device available"); 
 
      _capturectrl.VideoDevices["Analog"].Selected = true; 
 
      // select video and audio compressors 
      _capturectrl.VideoCompressors.Mpeg2.Selected = true; 
      _capturectrl.AudioCompressors.AC3.Selected = true; 
 
      // set the target format to MPEG2 program 
      _capturectrl.TargetFormat = TargetFormatType.MPEG2Program; 
 
      if (_capturectrl.HasDialog(CaptureDlg.TargetFormat)) 
         _capturectrl.ShowDialog(CaptureDlg.TargetFormat, _form); 
 
      // tune to a channel with closed captions 
      _capturectrl.TVTuner.SetChannel(28, -1, -1); 
 
      // set the target file 
      _capturectrl.TargetFile = outFile; 
 
      // enable the preview 
      _capturectrl.Preview = true; 
 
      // check whether closed captioning is enabled 
      if (_capturectrl.ClosedCaptionAvailable 
         && _capturectrl.ClosedCaptioning == false) 
      { 
         // try to toggle closed captioning  
         _capturectrl.ToggleClosedCaptioning(); 
 
         // set the result to what we expect 
         if (_capturectrl.ClosedCaptioning) 
            _result = true; 
 
         // get the previewing cc state 
         bool _previewCC = _capturectrl.PreviewingClosedCaption; 
      } 
 
      // check whether we can capture video 
      if (_capturectrl.IsModeAvailable(CaptureMode.VideoAndAudio)) 
      { 
         _capturectrl.TimeLimit = 30;      // just 30 seconds of capture time 
         _capturectrl.UseTimeLimit = true; 
 
         // 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(); 
 
         _result = true; 
      } 
   } 
   catch (Exception) 
   { 
      _result = false; 
   } 
 
   // 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(); 
} 
 
static class LEAD_VARS 
{ 
   public const string MediaDir = @"C:\Program Files (x86)\LEAD Technologies\LEADTOOLS 20\Media"; 
}

Imports Leadtools 
Imports Leadtools.Multimedia 
Imports LeadtoolsMultimediaExamples.Fixtures 
 
Public _result As Boolean = False 
Public _form As CaptureCtrlForm = New CaptureCtrlForm() 
Public _capturectrl As CaptureCtrl 
 
Public Sub ClosedCaptioningExample() 
   ' reference the capture control 
   _capturectrl = _form.CaptureCtrl 
 
   ' output file names 
   Dim outFile As String = Path.Combine(LEAD_VARS.MediaDir, "CaptureCtrl_ClosedCaptioningExample_DVD") 
 
   Try 
      ' try to find a Digital tuner, use your device name here 
      If _capturectrl.VideoDevices("Analog") Is Nothing Then 
         Throw New Exception("No Analog video device available") 
      End If 
 
      _capturectrl.VideoDevices("Analog").Selected = True 
 
      ' select video and audio compressors 
      _capturectrl.VideoCompressors.Mpeg2.Selected = True 
      _capturectrl.AudioCompressors.AC3.Selected = True 
 
      ' set the target format to MPEG2 program 
      _capturectrl.TargetFormat = TargetFormatType.MPEG2Program 
 
      If _capturectrl.HasDialog(CaptureDlg.TargetFormat) Then 
         _capturectrl.ShowDialog(CaptureDlg.TargetFormat, _form) 
      End If 
 
      ' tune to a channel with closed captions 
      _capturectrl.TVTuner.SetChannel(28, -1, -1) 
 
      ' set the target file 
      _capturectrl.TargetFile = outFile 
 
      ' enable the preview 
      _capturectrl.Preview = True 
 
      ' check if closed captioning is enabled 
      If _capturectrl.ClosedCaptionAvailable AndAlso _capturectrl.ClosedCaptioning = False Then 
         ' try to toggle closed captioning  
         _capturectrl.ToggleClosedCaptioning() 
 
         ' set the result to what we expect 
         If _capturectrl.ClosedCaptioning Then 
            _result = True 
         End If 
 
         ' get the previewing cc state 
         Dim _previewCC As Boolean = _capturectrl.PreviewingClosedCaption 
      End If 
 
      ' check if we have can capture video 
      If _capturectrl.IsModeAvailable(CaptureMode.VideoAndAudio) Then 
         _capturectrl.TimeLimit = 30 ' just 30 seconds of capture time 
         _capturectrl.UseTimeLimit = True 
 
         ' 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 
 
         _result = True 
      End If 
   Catch e1 As Exception 
      _result = False 
   End Try 
 
   ' 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 Sub 
 
Public NotInheritable Class LEAD_VARS 
   Public Const MediaDir As String = "C:\Program Files (x86)\LEAD Technologies\LEADTOOLS 20\Media" 
End Class

Requirements

Target Platforms

Reference

CaptureCtrl Class

CaptureCtrl Members

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Help Version 20.0.2020.4.2

Leadtools.Multimedia Assembly

Introduction

Getting Started

Namespaces

Leadtools.Multimedia Namespace

Leadtools.Multimedia.Common Namespace

Assemblies