Use the grab functions to perform a continuous acquisition into a single buffer.
To use the grab functions, call imgGrabSetup to configure the session for grabbing and optionally start the acquisition process. If you do not start the acquisition using imgGrabSetup, you must start it by calling imgSessionStartAcquisition prior to calling the imgGrab and imgGrabArea functions.
After the acquisition has started, obtain an image by calling imgGrab and imgGrabArea. To stop the acquisition, call imgSessionStopAcquisition.