Traffic flow / Traffic flux is a generic term used to describe vehicle movement and volume over a transportation network. Two important parameters of traffic flow are average annual daily traffic (AADT) and Vehicle miles traveled.
These are long term flow patterns. Short term pattern includes daily or hourly parameters broken down to vehicle categories are also of high interest. This data can be acquired only with limited spatial extent with traditional techniques. The use of airborne / satellite imagery, however offers an excellent temporal and spatial resolution that can easily provide for sizable area of sight coverage at fast sampling rates. This definitely makes the whole system uneconomical and complex because of satellites and allied infrastructure. Answer to this data acquisition with digital cameras and analysis through the computer/machine vision technique/algorithms.