A vehicle speed acquiring unit acquires a vehicle speed. A moving range calculating unit calculates, based on the vehicle speed, a pre-stop moving range within which the vehicle may cover before coming to a stop. A sensor information acquiring unit acquires object detection information indicating a detected object, detected by a sensor, in the surroundings of the vehicle. An image superposing unit superposes the pre-stop moving range and the position of the detected object included in the object detection information on top of each other on a screen. In addition, the image superposing unit generates a superposed image that displays the position of a detected object estimated, based on position information of the detected object included in the object detection information, to have a possibility of overlapping the pre-stop moving range, more saliently than the positions of other detected objects. An image presenting unit presents the generated superposed image.