Display
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Description

Enables/disables live display in the control window. When this property is enabled, each frame will be automatically displayed upon acquisition.


Syntax


[VB]
objActiveDcam.Display [= Value]


[C/C++]
HRESULT get_Display ( bool *pDisplay );
HRESULT put_Display( bool Display );



Data Type
[VB]

Boolean


Parameters
[C/C++]

pDisplay [out,retval]  
Pointer to the Boolean that is TRUE if the live display is enabled, or FALSE otherwise  
Display [in]  
Set to TRUE to enable the live display, or set to FALSE to disable it  


Return Values


S_OK  
Success  
E_FAIL  
Failure.  
 

Example


This VB example disables the live display and uses the FrameAcquired event to invert pixel value in the bottom left corner of the current frame and display the processed frame in real time.

Private Sub
 Form_Load()

ActiveDcam1.Display =
 False

ActiveDcam1.Acquire =
 True

End Sub


Private Sub ActiveDcam1_FrameAcquired()
a = ActiveDcam1.GetImageData

For
 x = 0 To 200
For
 y = 0 To 200
a(x, y) = 255 - a(x, y)

Next
Next

ActiveDcam1.Draw

End Sub

 

Remarks


When you create a new instance of the control, this property is enabled by default. You should disable the live display when you want to perform real time image processing and display the processed image in the control window. After the processing is done, the current frame should be displayed by calling the Draw method.

When using DirectShow Video Capture Filter, this property controls the internal conversion to RGB24 format which is required by image data access and image analysis methods, such as GetImageData, GetComponentData, GetImageLine, GetImageWindow, GetHistogram, GetImageStat and others. Setting Display to FALSE will disable the conversion and provide original video formats on the output pin.

Note that disabling the live display does not turn off the image conversion performed on each frame. In order to disable the image conversion pipeline and receive only raw image data, set the Magnification property to -2.