Apparatus and method for localisation and mapping

A data processing apparatus comprises receiving circuitry to receive a plurality of images of an environment captured from respective different viewpoints, detection circuitry to detect a plurality of feature points in the plurality of captured images and to associate image information with each detected feature point indicative of an image property for a detected feature point, wherein each detected feature point represents a candidate landmark point for mapping the environment, selection circuitry to select one or more of the plurality of candidate landmark points, the one or more selected landmark points corresponding to a subset of the plurality of candidate landmark points, and mapping circuitry to generate, for the environment, a map comprising one or more of the selected landmark points, wherein each landmark point included in the map is defined by a three dimensional position and the associated image information for that landmark point.