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CaptureHDIB Method

Summary

Captures a device independent bitmap.

Syntax

C++/CLI

public virtual IntPtr CaptureHDIB()

public:  
   virtual System::IntPtr CaptureHDIB()

Return Value

System.IntPtr

Remarks

If the method succeeds, the caller must free the returned HDIB pointer by calling the Marshal.FreeHGlobal method. 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 DIB. Finally, it stops the graph by calling StopCapture.

Note: The frame data is retrieved from the underlying graph after the processing filters. If the capture needs to occur before the processing is completed use the LeadVideoCallBackFilter and place it first in the collection of processing filters.

Example

using Leadtools; 
using Leadtools.Multimedia; 
using LeadtoolsMultimediaExamples.Fixtures; 
 
 
public bool _result = false; 
public CaptureCtrlForm _form = new CaptureCtrlForm(); 
 
public void CaptureDIBExample() 
{ 
   // reference the capture control 
   CaptureCtrl capturectrl = _form.CaptureCtrl; 
 
   try 
   { 
      // set the video capture device. use your device's name here 
      if (capturectrl.VideoDevices["Logitech"] == null) 
         throw new Exception("No Logitech video device available"); 
 
      capturectrl.VideoDevices["Logitech"].Selected = true; 
 
      // set a delay of 1 second to ensure that some capture devices 
      // have time to adjust their gain 
      capturectrl.CaptureStillDelay = 1000; 
 
      // capture device independent bitmap 
      IntPtr dib = capturectrl.CaptureHDIB(); 
 
      _result = (dib != null); 
 
      //free allocated global memory 
      Marshal.FreeHGlobal(dib); 
   } 
   catch (COMException) 
   { 
      _result = false; 
   } 
   catch (Exception) 
   { 
      _result = false; 
   } 
}

Requirements

Target Platforms