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CaptureImage Method
See Also 
Leadtools.Multimedia Namespace > CaptureCtrl Class : CaptureImage Method



Captures a video image to a System.Drawing.Image object.

Syntax

Visual Basic (Declaration) 
Public Overridable Function CaptureImage() As Image
Visual Basic (Usage)Copy Code
Dim instance As CaptureCtrl
Dim value As Image
 
value = instance.CaptureImage()
C# 
public virtual Image CaptureImage()
C++/CLI 
public:
virtual Image^ CaptureImage(); 

Return Value

captured video image as a System.Drawing.Image.

Example

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

         Dim inFile As String = Path.Combine(LEAD_VARS.MediaDir, "CaptureCtrl_Source.avi")
         Dim outFile As String = Path.Combine(LEAD_VARS.MediaDir, "CaptureCtrl_CaptureImageExample.jpg")

         Try
            ' set the video capture device, use your capture device name here
            If capturectrl.VideoDevices("USB") Is Nothing Then
               Throw New Exception("No USB video device available")
            End If

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

            ' capture the image
            Dim image As Image = capturectrl.CaptureImage()

            If Not image Is Nothing Then
               image.Save(outFile, ImageFormat.Jpeg)
            End If

            ' stop the capture
            capturectrl.StopCapture()

            ' check for the capture file and set the result
            If File.Exists(Path.Combine(Directory.GetCurrentDirectory(), outFile)) Then
               _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 Sub CaptureImage_Helper(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
C#Copy Code
public bool _result = false;
      public CaptureCtrlForm _form = new CaptureCtrlForm();
      public void CaptureImageExample()
      {
         // reference the capture control
         CaptureCtrl capturectrl = _form.CaptureCtrl;

         string inFile = Path.Combine(LEAD_VARS.MediaDir,"CaptureCtrl_Source.avi");
         string outFile = Path.Combine(LEAD_VARS.MediaDir,"CaptureCtrl_CaptureImageExample.jpg");

         try
         {
            // set the video capture device, use your capture device name here
            if (capturectrl.VideoDevices["USB"] == null)
               throw new Exception("No USB video device available");

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

            // capture the image
            Image image = capturectrl.CaptureImage();

            if (image != null)
               image.Save(outFile, ImageFormat.Jpeg);

            // stop the capture
            capturectrl.StopCapture();

            // check for the capture file and set the result
            if (File.Exists(Path.Combine(Directory.GetCurrentDirectory(), outFile)))
               _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();
      }

      public void CaptureImage_Helper(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";
}

Remarks

This method will capture a video image to a System.Drawing.Image object.

If the method fails, an error is raised. For more information, refer to the Error Codes.

Note: Internally this method calls StartCapture with the capture mode set to CaptureMode.Still. It then waits for the current capture delay setting specified by CaptureStillDelay before capturing the still picture. Finally, it stops the graph by calling StopCapture.

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