Watermarking Spatial Data in Geographic Information Systems

摘要

Spatial data integration and exchange has become a very important issue with the emergence and proliferation of interoperability of Geographic Information Systems, making data sharing within the GIS user communities possible. The GIS foreground data is application specific and contains locational intelligence that may be considered confidential. Watermarking the multimedia data is a widely accepted and used method which involves introducing intentional errors into the data sets to mark its ownership. This paper looks into the issue of the protection of the spatial data ownership in such networked, multi-user operating environments, and proposes two algorithms for watermarking the GIS foreground data for this purpose. First algorithm is for watermarking the GIS foreground data which is assumed to be a set of vector data stored in a relational table. Second algorithm is for detecting the watermark to establish its ownership. These two algorithmic models can be implemented in a relevant programming language. It is suggested that relevant GIS applications should implement such algorithms as a system component to watermark the foreground data sets produced.