Toward Automatic Updating of the Israeli National Gis - Phase Ii

Spatial Information revision and updating is the main concern and production effort of maintaining the ever-growing GIS systems and spatial data bases. Developing easily effected automatic updating methods of spatial information becomes the key to the successful maintenance of the large GIS data bases established by many mapping agencies all over the world. The paper presents the second phase in a multi-year research effort for the development of capabilities of automatic updating of the Israeli National Spatial Data Base. This ongoing research is funded by the Survey of Israel within the framework of maintaining the Israeli National GIS (was reported on the ISPRS’ IC meeting in Haifa, September 1997). Discussed are the experiments and the evaluation steps to define an efficient method for detection of change. Presented are the guidelines and results of the development of an autonomous process to define change thresholds as part of an automatic change detection step. Also discussed are methods for noise removal and gaps bridging, necessary for expediting execution time and the efficiency of the overall process. Presented are experiments with filtering methods, in the raster domain, and with buffering methods, in vector domain. In addition, presented are the research efforts to develop capabilities of feature recognition and shape identification, as the basis for change identification (third phase in the research). Also discussed are the experiments and effort to develop GIS-Driven capabilities for a multi-source change detection process as part of an automatic GIS data base updating method.