The blurring caused by a tiny tremor movement is eliminated, which almost perfectly without being affected by intentional camera movement by distinguishing the unintentional tremor movement from other movements (or disturbances). A motion detector includes: a motion detecting section for detecting a movement of an image capture device and outputting a detection signal, of which the amplitude and frequency represent the movement; a motion signal generating section for generating a motion signal representing a physical quantity corresponding to the magnitude of the movement based on the detection signal; a notification signal generating section for generating a notification signal that marks start and end of a movement of the image capture device, which is a non-tremor movement, based on the detection signal that has been output; and a control section for controlling the motion signal generating section by reference to the notification signal such that an output of the motion signal is fixed at a predetermined one from the start through the end of the non-tremor movement.