An autometic traffic light control system in a four roaded junction point

at a four road junction points traffic light should be controlled according to traffic rush?CC camera, counter allowed. How to resolve? If CC tv camera is used of course an image anlysis that is pattern recognition system to be used here. What about keeping a LASER tracker at entry of road that will count up vehicles on each lane.. then keeping a weeks info, for next week according to time setting according to rush duration the traffic lights holding time? a week is not enough though.How to start thinking?👎