The present invention relates to generating position determination information. A corresponding system comprises an image receiving means (102) for obtaining at least one image of the environment, and a control point information obtaining means (104) for obtaining control point position information about a position of at least one control point (152) in the environment. The system also comprises an image processing means (108) for associating said control point position information about a position of the at least one control point (152) in the environment to an image of the at least one control point (152) in the at least one image of the environment and for deriving, from the at least one image of the environment, position information of at least one object (202) in the environment taking into account the associated position information of the image of the at least one control point (152). An accuracy control means allows controlling the obtained accuracy by controlling the control points used.