Person counting is one of the most everyday useful functions of the BASS system. Users draw lines anywhere on any feed and assign a positive and negative direction for crossing it. The system has an ongoing count of that line, saving both positive crosses (entries) and negative crosses (exits). The count continues until it is reset, or unless it is programmed to reset regularly, every 24 hours for instance, using state management. At any given time, the positive minus the negative crosses for all lines drawn on building entry points gives the current capacity. Lines can also be used to answer questions about traffic flow within businesses (checkout aisle usage, amenity use at hotels, etc). Outdoor cameras can also give data on foot traffic outside businesses to give data on signage and marketing efficacy.