INFORMATION PROCESSING DEVICE, CONTROL METHOD, PROGRAM AND STORAGE MEDIUM

A control unit of an in-vehicle device configured to acquire, from landmark data LD that is map data including position information of one or more features, plural pieces of position information of a feature which is drawn on a road surface and which exists at or around a vehicle. Then, the control unit is configured to calculate a normal vector of an approximate plane calculated based on the acquired plural pieces of the position information. Then, the control unit is configured to calculate at least one of a pitch angle or a roll angle of the vehicle based on the orientation of the vehicle and the normal vector.