Abstract: A monitoring system for monitoring a target is described. The monitoring system extracts features of a person's face from an image obtained from the face of the person and determines whether the person's face matches a person included in a list containing facial features of multiple individuals.

Abstract: A monitoring system configured to monitor a monitoring target, the monitoring system includes: a face feature quantity extraction unit configured to extract a person's face feature quantity from input images captured by first and second imaging devices; a matching unit configured to determine whether a person in the input image is a person of a face feature quantity list by comparing the face feature quantities, wherein a second face feature quantity list is a subset or an empty set of a first face feature quantity list, the matching unit matches the face feature quantity of the person in the input image captured by the first imaging device against each face feature quantity of the first face feature quantity list, and matches the face feature quantity of the person in the input image captured by the second imaging device against each face feature quantity of the second face feature quantity list.