Provided is a head-mounted device that includes a housing, first imaging means, and second imaging means. The housing is to be mounted on the head of a user. The first and second imaging means are mounted on the housing to capture images from different angles of view. The head-mounted device receives an image captured by the first imaging means, detects an image portion corresponding to a body portion of the user from the received image, and estimates, based on information indicative of the detected image portion, a possible existence range of a predetermined part of the body of the user within an image captured by the second imaging means.