A clustering approach for protecting gis vector data

Abstract

The availability of Geographic Information System (GIS) data has increased in recent years, as well as the need to prevent its unauthorized use. One way of protecting this type of data is by embedding within it a digital watermark. In this paper, we build on our previous work on watermarking vector map data, to improve the robustness to (unwanted) modifications to the maps that may prevent the identification of the rightful owner of the data. More specifically, we address the simplification (removing some vertices from GIS vector data) and interpolation (adding new vertices to GIS data) modifications by exploiting a particular property of vector data called a bounding box. In addition, we experiment with bigger maps to establish the feasibility of the approach for larger maps.