A vehicle detection apparatus detects vehicles traveling on a road with
their lights turned on. The apparatus captures images of a road, detects
a light spot from captured images, and detects a first vertical
coordinate of the light spot in the images. The apparatus further
calculates a distance to the light spot based on a horizontal length of
the light spot in the images and detects a second vertical coordinate
corresponding to the calculated distance, based on correlated data in
which vertical coordinates and distances in an image are correlated in
advance. The apparatus further calculates a pitching amount that
indicates a difference between the first and second coordinates and
determines whether or not the light spot originates from a vehicle, based
on the pitching amount.