FALLING OBJECT DETECTION APPARATUS, IN-VEHICLE SYSTEM, VEHICLE, AND COMPUTER READABLE MEDIUM

An acquisition unit of a falling object detection apparatus installed and used in a first vehicle acquires a depth image of a second vehicle, on which a load is mounted and which is traveling in front of the first vehicle, and of the area around the second vehicle. A determination unit of the falling object detection apparatus determines whether the load has not made a movement different from that of the second vehicle, using the depth image acquired by the acquisition unit. A detection unit of the falling object detection apparatus detects a fall of the load based on a result of determination by the determination unit.