1. An image shooting device, comprising: a moving image shooting section adapted to shoot a moving image; a person detector adapted to detect a person in the moving image and set the person as a detected person; a person information storage adapted to track a movement of the detected person and store therein action of the detected person exhibited during a certain period of time in past; a person evaluator adapted to evaluate the detected person based on the action of the detected person exhibited during the certain period of time in the past and give the detected person a score; a person determiner adapted to determine that the detected person is a target person who a shooting person of the moving image intends to shoot, when the score of the detected person is higher than a predetermined value; and a shooting assist section adapted to assist action of at least one of the shooting person and the target person so that the target person is included in the moving image.