Thronging determination device and thronging determination method

A thronging determination device for determining occurrence of a thronging state in which persons are gathered locally, includes an image receiving unit that receives a moving image, an image dividing unit that divides an input image received by the image receiving unit into local regions, and a degree-of-congestion estimating unit that judges the degree of congestion in plural ones of the local regions. If the degree-of-congestion estimating unit judges that the degree of congestion in the plural ones of the local regions is lower than a prescribed value, a thronging determination is performed using local regions that are smaller in number than the local regions that have been used in estimating the degree of congestion.