1. A method of detecting a position and a location of a camera with respect to a topographical map, comprising the steps: a) obtaining existing topographical map data; b) obtaining a predicted camera position and location that a camera is predicted to have during a planned trajectory; c) producing a local 3D model from the existing topographical map data, wherein the local 3D model contains only such localized map features of the existing topographical map data that would be imaged by the camera at the predicted camera position and location; d) producing a virtual image from the local 3D model; e) in an off-line process, producing a feature database from the virtual image; and f) in an online process, using the feature database to recognize actual features that have been imaged by the camera during an actual trajectory.