Dynamic geospatial image mosaics using JAVA, JAI, RMI and CORBA

Abstract

Command Control, Computers, Communications, Intelligence, and Surveillance (C4ISR) systems make extensive use of geospatial and image based information. Map displays and aerial photography are often used as the backdrop for the display of other information in systems to assist in providing situation awareness. Given the desire to have high-resolution information, the volume and variety of geospatial information is increasing. Both commercial and experimental systems are being developed to manage, serve and process these large volumes of image and geospatial information. This paper describes the development of a dynamic server that communicates with an experimental CORBA based backend image repository, and to a JAVA map display client to deliver a virtual mosaic of the imagery within the displayed region. Since imagery is not always stored in georeferenced form we have had to provide a processing chain that maps the image coordinates to the map coordinates for display. This is implemented using the JAVA Advanced imaging library. To reduce the footprint of the client the dynamic server that processes the imagery from the backend repository can be distributed off of the client system via an RMI connection. To maximise the interactive performance of this application various types of caching of queries and image data have been implemented.