AUGMENTED MAPS

Cartographic visualizations are usually given as printed maps or screen maps. On the one hand the user can directly interact with a flat paper-map in a natural and familiar way like all other physical things in our environment. On the other hand there is a possibility to extend the dimensions of a map to more then two by the means of computer-vision. Three-dimensional landscapes and animation can be created and visualized. The usability depends to a great degree on the experience of the user and the possibilities of the computer program. Augmented Reality (AR) combines these characteristics, in that it places well known ways of handling and all potentialities of computer-science to the users disposal. In our approach the actual position and line of vision referring to the map is determined by the use of pattern-recognition techniques. Unambiguous tags are placed on the border of the map. These tags are captured by a small video camera. The computer determines all parameters for overlaying and combining the video-stream of reality with artificial virtual objects. As this calculation can be performed individually for different users, they can look at the same data and see the combination of reality and virtual objects. So every user can interact with the map in his own way and e.g. activate new layers or point on virtual object to get additional information. This technique enables cartographic applications to visualize and work on digital geographic data based on an analogue map. As an example the visualization of a digital terrain model in combination with the corresponding topographic map is shown.