An object of the present invention is to reduce false detection of an eyelid from a face image. According to the present invention, it is determined whether the amount of the change in the position of an eyelid outline candidate line during blinking matches the normal movement of an eyelid. When it is determined that the amount of the change in the position of the eyelid outline candidate line does not match the normal movement of the eyelid during blinking, the eyelid outline candidate line is not set as an eyelid outline. Therefore, it is possible to reduce false detection of the eyelid from the face image.