The in-vehicle device transfers the selected image selected by the user from the photographed images stored in the storage device and the selected vehicle state, which is the vehicle state when the selected image is captured, to the portable device. The portable device executes a portable side determination process for determining whether or not the selected image is a rare image by using the selected image and the selected vehicle state, and transmits the selected image determined to be a rare image by the portable side determination process and the selected vehicle state to the image management server only when the transmission is permitted by the user. The image management server stores the selected image and the selected vehicle state transmitted from the portable device in the image storage device.