Patent ID: 7064778

Claim:
A closed circuit video system that utilizes shared video memory, said system having: a plurality, N, of image capture devices each producing a corresponding video signal so as to define a plurality of N video signals; a circuit, responsive to said plurality of video signals, which in response to a selection control signal, routes a specific group, M, of selected ones of said video signals produced by M respective ones of the N image capture devices to associated output devices, where M and N are positive integers; and wherein said circuit comprises: a separate memory for each one of said M video signals, said separate memory implements a multi-functional shared store for its associated one of the M image capture devices, through which said separate memory supports video processing functionality associated with standard shutter imaging and slow shutter imaging as well as video processing functionality for other operations provided through said circuit such that said separate memory eliminates a need to have a separate frame store situated within or proximate to said associated one image capture device to implement slow shutter imaging, wherein, during standard shutter imaging and slow shutter imaging, the separate memory is updated at a field rate appropriate to said associated one image capture device and read out at a rate appropriate to an image store function; and said separate memory communicatively interacts with said associated one image capture device through which said associated one image capture device specifies, in response to whether said associated one image capture device is functioning in said standard or slow shutter imaging, if the separate memory should then update its video contents or not in response to a corresponding one of the video signals then being produced by said associated one image capture device.