Considerations on watermarking security

In this paper we address the usually implicit assumption that digital watermarking has as its main target copyright and copy protection applications. From these target applications a great many conclusions are drawn about the required security of a watermarking system, and in fact, a considerably percentage of the watermarking literature has this very topic as its main focus of attention. In this paper we take a step back, and try to do a more careful analysis of the 'watermarking-is-for-security-applications' paradigm. The intention of this paper is to discuss the meaning of the concept security in the context of watermarking, and try to show that one has to be careful in using analogies from the related field of cryptography.