OBJECT MONITORING METHOD, OBJECT MONITORING DEVICE, AND OBJECT MONITORING PROGRAM

摘要

The present invention relates to an object monitoring method and so forth that monitors the presence or absence of a change in an object by performing a comparison between a reference image and a comparison image acquired by capturing the object. An object of the invention is to accurately capture a change between the reference image and the comparison image even when image capture conditions, such as illumination conditions, are different from one another in the events of capturing the images. The method includes a pixel-value correction step that causes an average and variance of pixel values in a second subregion inclusive of a first subregion inclusive of being formed of only one pixel in a comparison image resolved into pixels to match with an average and variance of pixel values in a subregion corresponding to the second subregion on a reference image similarly resolved into pixels, thereby to execute calculation that corrects the pixel value of each pixel in the first subregion in the comparison image by recognizing each of subregions to be the first subregion, the subregions being obtained when the comparison image is divided into the subregions respectively inclusive of being formed of only one pixel; and a change determination step that determines the presence/absence of a change in the object by comparing the reference image with a post-correction comparison image acquired through the pixel value correction step.