This device includes an input unit for inputting an imaging signal sent from a camera for imaging an area around a vehicle in which the device is loaded, a coordinate area extracting unit for extracting predetermined continuous coordinate areas from the imaging signal inputted by the input unit, a feature quantity calculating unit for calculating a feature quantity of the coordinate areas extracted by the coordinate area extracting unit, a pairing unit for pairing the coordinate areas having the same or closer feature quantities, calculated by the feature quantity calculating unit, the coordinate areas being included in the coordinate areas extracted by the coordinate area extracting unit, with each other, and an output unit for outputting a signal that designates a distance between and a direction of the coordinate areas paired by the pairing unit.