VEHICLE TRAJECTORY EXTRACTION METHOD, VEHICLE REGION EXTRACTION METHOD, VEHICLE SPEED ESTIMATION METHOD, VEHICLE TRAJECTORY EXTRACTION PROGRAM, VEHICLE REGION EXTRACTION PROGRAM, VEHICLE SPEED ESTIMATION PROGRAM, VEHICLE TRAJECTORY EXTRACTION SYSTEM, VEHICLE REGION EXTRACTION SYSTEM, AND VEHICLE SPEED ESTIMATION SYSTEM

摘要

PROBLEM TO BE SOLVED: To extract a trajectory of a vehicle region, and others from a traffic flow moving image without being affected by surrounding brightness.SOLUTION: A plurality of images having time differences are acquired from an imaging device photographing a prescribed place on a road, a time difference image binarized from points of a luminance change between arbitrary two images photographed in temporal succession is acquired from the plurality of images, the time difference images are accumulated, and at that time, an accumulation time difference image is acquired by removing an image portion in which the luminance change is relatively small. Furthermore, a trajectory of a vehicle region from which a shadow region is removed is extracted by imposing the accumulation time difference images in a temporal direction. Conversely from the trajectory, the vehicle region or a vehicle speed can be obtained.