Abnormality detection device, abnormality detection method, and abnormality detection system

Abstract

A technique is provided for detecting the presence or absence of an abnormality with respect to an object appearing in a target image with high accuracy without using AI, even in an environment in which luminance values and colors are likely to fluctuate. An abnormality detection device () includes: an image input unit () for inputting an input image indicating an abnormality detection target object; a gradient distribution generation unit () for dividing the input image into predetermined regions and generating, for each region, a gradient distribution that indicates a distribution of a luminance gradient direction of the region; and an abnormality determination unit () for determining the presence or absence of an abnormality by analyzing the gradient distribution generated for each region.