a vehicle detection system for providing data characteristic of traffic conditions includes a camera overlooking a roadway section for providing video signals representative of the field , and a digitizer for digitizing these signals and providing successive arrays of pixels characteristic of the field at successive points in space and time . a video monitor coupled to the camera provides a visual image of the field of view . through use of a terminal and in conjunction with the monitor , an operator controls a formatter so as to select a subarray of pixels corresponding to specific sections in the field of view . a microprocessor then processes the intensity values representative of the selected portion of the field of view in accordance with spatial and / or temporal processing methods to generate data characteristic of the presence and passage of vehicles . this data can be utilized for real - time traffic surveillance and control , or stored in memory for subsequent processing and evaluation of traffic flow conditions .