Digital watermark-based security technology for geo-spatial graphics data

Abstract

The paper presents a set of techniques of digital watermarking by which copyright and user rights messages are hidden into geo-spatial graphics data, as well as techniques of compressing and encrypting the watermarked geo-spatial graphics data. The technology aims at tracing and resisting the illegal distribution and duplication of the geo-spatial graphics data product, so as to effectively protect the data producer’s rights as well as to facilitate the secure sharing of geo-spatial graphics data. So far in the GIS field throughout the world, few researches have been made on digital watermarking. The research is a novel exploration both in the field of security management of geo-spatial graphics data and in the applications of digital watermarking technique. An application software employing the proposed technology has been developed. A number of experimental tests on the 1:500,000 digital bathymetric chart of the South China Sea and 1:10,000 digital topographic map of Jiangsu Province have been conducted to verify the feasibility of the proposed technology.