Position
estimation device (1) with: - an
image capture unit (11) configured to capture a plurality of images from a plurality of cameras (20a to 20d) mounted on a vehicle (2) to capture images around the vehicle (2), wherein the plurality of cameras (20a to 20d) are mounted to form a plurality of overlapping areas (3, 4, 5, 6), the overlapping areas (3, 4, 5, 6) being areas in which image areas partially overlap each other; - a detection unit (11, 12, S100 to S110) configured to detect at least one feature portion, which is a portion indicating a predetermined feature in an area on each of a plurality of images each including appearances of the overlapping areas (3, 4, 5, 6), the plurality of images being detected by the
image detection unit (11) at approximately the same time; - an
estimation unit (12, 13, S112 to S118) configured to calculate, for each of the overlapping areas (3, 4, 5, 6), an amount of positional offset between the feature portions acquired from the plurality of images each including appearances of the overlapping areas (3, 4, 5, 6), and to estimate a predetermined
physical quantity associated with an attitude of the vehicle (2) based on a difference in the amount of offset calculated for each of the plurality of overlapping areas (3, 4, 5, 6); - a position information output unit (14, S130) configured to output information based on a
physical quantity estimated by the
estimation unit (12, 13, S112 to S118) as position information, which is information indicating a position of the vehicle (2); - a reliability determination unit (14, S120, S122) configured to determine a reliability of a gyro sensor (21) provided in the vehicle (2) based on a result of a comparison of a posture of the vehicle (2) indicated by a
physical quantity estimated by the estimation unit (12, 13, S112 to S118) with a measurement associated with a posture of the vehicle (2) derived from the gyro sensor (21); and - a reliability information output unit (14, S124) configured to output unreliability information, which is information indicating that the reliability of the gyro sensor (21) is determined to be unreliable when the reliability of the gyro sensor (21) is determined to be unreliable by the reliability determination unit (14, S120, S122).