  Analysis of video images is a common way to determine the properties of an
electron or synchrotron radiation beam. At BESSY a cost-efficient frame grabber
hardware controlled by a Windows PC allows one to perform such an analysis in
real-time. Live video images on the PC monitor give operators a direct view of
the beam, optionally enhanced by artificial coloring and graphical overlays.
The application software has been integrated into the EPICS environment by
including a Channel Access (CA) server. Thus the numerical results and the
application's control commands are accessible over a network through CA Process
Variables. A newly developed C++ class library is used to provide the variables
with the usual attributes required by advanced CA clients such as graphical
display managers.
