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AutoContrast Property

Summary

Gets or sets the automatic setting for the Contrast property.

Syntax

C++

public bool AutoContrast { get; set; }

Public Property AutoContrast As Boolean

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

Property Value

true if the property is controlled automatically; false if it has been set to a manual value

Remarks

If this property is true, the Contrast property is the current automatically controlled value. If this property is false, then the Contrast property returns the current manual value last set by the user.

Example

using Leadtools; 
using Leadtools.Multimedia; 
using LeadtoolsMultimediaExamples.Fixtures; 
 
public bool _result = false; 
public CaptureCtrlForm _form = new CaptureCtrlForm(); 
public string _outFile = Path.Combine(LEAD_VARS.MediaDir, "VideoProcAmp_SetAutoValueExample.avi"); 
 
// this example demonstrates how to set an auto value on the 
// video proc amp object. 
 
public void SetAutoValueExample() 
{ 
   // reference the capture control 
   CaptureCtrl capturectrl = _form.CaptureCtrl; 
 
   try 
   { 
      // select the first device with Logitech in it's name 
      // Replace "Logitech" with your video capture device name 
      if (capturectrl.VideoDevices["Logitech"] == null) 
         throw new Exception("No Logitech video devices available!"); 
 
      capturectrl.VideoDevices["Logitech"].Selected = true; 
 
      // set a video compressor 
      capturectrl.VideoCompressors.Mpeg2.Selected = true; 
 
      // set the target file 
      capturectrl.TargetFile = _outFile; 
 
      // reference the video proc amp 
      VideoProcAmp videoprocamp = capturectrl.VideoProcAmp; 
 
      // try to set the auto value 
      if (videoprocamp != null) 
         videoprocamp.AutoSaturation = true; 
 
      // check for video capture available 
      if (capturectrl.IsModeAvailable(CaptureMode.Video)) 
      { 
         // capture 15 seconds of video 
         capturectrl.UseTimeLimit = true; 
         capturectrl.TimeLimit = 15; 
 
         // subscribe to the compete event 
         capturectrl.Complete += new EventHandler(CaptureCtrl_Complete); 
         // start the capture 
         capturectrl.StartCapture(CaptureMode.Video); 
      } 
   } 
   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(); 
} 
 
void CaptureCtrl_Complete(object sender, EventArgs e) 
{ 
   // set the result to what we expect 
   _result = File.Exists(_outFile); 
} 
 
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 _outFile As String = Path.Combine(LEAD_VARS.MediaDir, "VideoProcAmp_SetAutoValueExample.avi") 
 
' this example demonstrates how to set an auto value on the 
' video proc amp object. 
 
Public Sub SetAutoValueExample() 
   ' reference the capture control 
   Dim capturectrl As CaptureCtrl = _form.CaptureCtrl 
 
   Try 
      ' select the first device with analog in it's name 
      ' Replace "Analog" with your video capture device name 
      If capturectrl.VideoDevices("Logitech") Is Nothing Then 
         Throw New Exception("No Logitech video devices available!") 
      End If 
 
      capturectrl.VideoDevices("Logitech").Selected = True 
 
      ' set a video compressor 
      capturectrl.VideoCompressors.Mpeg2.Selected = True 
 
      ' set the target file 
      capturectrl.TargetFile = _outFile 
 
      ' reference the video proc amp 
      Dim videoprocamp As VideoProcAmp = capturectrl.VideoProcAmp 
 
      ' try to set the auto value 
      If Not videoprocamp Is Nothing Then 
         videoprocamp.AutoSaturation = True 
      End If 
 
      ' check for video capture available 
      If capturectrl.IsModeAvailable(CaptureMode.Video) Then 
         ' capture 15 seconds of video 
         capturectrl.UseTimeLimit = True 
         capturectrl.TimeLimit = 15 
 
         ' subscribe to the compete event 
         AddHandler capturectrl.Complete, AddressOf CaptureCtrl_Complete 
         ' start the capture 
         capturectrl.StartCapture(CaptureMode.Video) 
      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 
 
Private Sub CaptureCtrl_Complete(ByVal sender As Object, ByVal e As EventArgs) 
   ' set the result to what we expect 
   _result = File.Exists(_outFile) 
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

VideoProcAmp Class

VideoProcAmp 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