A program stored on a non-transitory computer readable medium executable on a computer to perform discriminating a fiducial marker from captured images successively output from a camera, based on marker information representing associations between fiducial markers and object identifiers, identifying start points of one or more structured markers in the captured images based on the discriminated fiducial marker and position information defined in association with the fiducial marker, determining states of the one or more structured markers continuing from the start points, and outputting an operation instruction in accordance with the determined states of the one or more structured markers to an object discriminated based on the object identifier associated with the discriminated fiducial marker.