This VI determines the state of the preview window.


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Controls and Indicators


          hCamera IN is the camera handle. This value is returned by Initialize.vi and is passed between Pixelink VIs as a reference.


            uPreviewState IN is an enumerated control with the following values:

  • START_PREVIEW - opens a preview window which displays the live video stream form the camera.

  • PAUSE_PREVIEW - pauses the preview video without closing the window.


  • STOP_PREVIEW - closes the preview window.

         hCamera OUT has the same value as hCamera IN.



Details


The preview window is useful to view the video streaming from the camera.


To start the preview window, the camera defined by the camera handle hCamera IN must be streaming video.  To start the video stream, call the SetStreamState VI and set uStreamState IN to START_STREAM.


It is not necessary to use a preview window to capture images.  The callback VIs, GetClip and GetNextFrame capture images independent of the preview window state.


This function can be called without a previous call to the SetPreviewSettings VI. In this case, the default parameters in the SetPreviewSettings command are assumed.


Note: See Error Handling for error input and output information and error codes.