Vision sensors operate based on the principle of image recognition. The vision sensor is a video camera configured using special software: a virtual zone is placed on the surface of a virtual street (portion of the street’s area) whose purpose is to recognise a vehicle. As a vehicle goes through this zone, it is detected (counted). During programming, the direction of the vehicles that are to be detected (recorded) is also specified. When programming the video sensors, it is necessary to also take other factors into account such as sensor sensitivity, location, detection angle, distance to the carriageway, and the width of the detected traffic lanes. Proper maintenance of the vision sensors and software updates reduce the margin of error in the calculations of transport flows.