Technical Methods for Encrypting and Hiding Digital Watermark in GIS Spatial Data

This paper presents a technical method for hiding digital watermark in GIS spatial data, which can identify the data producer and legal user's identity, user's using authority and some other related information, then compresses and encrypts the GIS data in order to track and resist the illegal circulation and copy to protect the data producer's legal right effectively. All of the methods have been put into practice as a set of software and its feedback is pretty good.