Copyright protection of vector data using vector watermark

Geographical Information System (GIS) is used to collect, manipulate, analyze, and display the geospatial data. The compilation and management of this spatial data is expensive and time consuming task. Due to rapid growth of distributed networks and Internet, it becomes easy to handle data but at the same time it becomes easy to copy or distribute the spatial data. Therefore copyright protection, authenticity, and spatial data source tracing have become important issues. One of the remarkable methods to solve these issues is digital watermarking. The objective of this paper is to propose a digital watermarking scheme which can be used for copyright protection of geospatial data using vector data as a watermark. In the proposed algorithm, vector watermark is embedded in low frequency coefficients at third level of wavelet decomposition. Experimental results show that the proposed algorithm is robust against all the attacks except compression attack for using vector data as watermark. It has been observed that increase in strength of embedding increases visual degradation.