FPGA Based Implementation of an Invisible-Robust Image Watermarking Encoder Saraju P. Mohanty 1 , Renuka Kumara C. 2 , and Sridhara Nayak 2 1 Dept. of Computer Science and Engineering, Univ. of North Texas, Denton, TX 76203, USA smohanty@cs.unt.edu 2 Manipal Centre For Information Science, Manipal Academy of Higher Education, Manipal – 576104, India shridhar.n@mcis.manipal.edu Abstract. Both encryption and digital watermarking techniques need to be in- corporated in a digital rights management framework to address different aspects of content management. While encryption transforms original multimedia ob- ject into another form, digital watermarking leaves the original object intact and recognizable. The objective is to develop low power, real time, reliable and se- cure watermarking systems, which can be achieved through hardware implemen- tations. In this paper, we present an FPGA based implementation of an invisi- ble spatial domain watermarking encoder. The watermarking encoder consists of a watermark generator, watermark insertion module, and a controller. Most of the invisible watermarking algorithms available in the literature and also the al- gorithm implemented in this paper insert pseudorandom numbers to host data. Therefore, we focus on the structural design aspects of watermarking generator using linear feedback shift register. We synthesized the prototype watermarking encoder chip using Xilinx FPGA. 1 Introduction Owing to the usage of Internet, concerns about protection and enforcement of intellec- tual property (IP) rights of the digital content involved in the transaction, are mounting. In addition, unauthorized replication and manipulation of digital content is relatively trivial and can be achieved using inexpensive tools. Issues related to ownership rights of digital content are addressed by digital rights management (DRM) systems [1, 2]. Various aspects of content management namely, content identification, storage, repre- sentation, and distribution and intellectual property rights management are highlighted in DRM. Besides, unauthorized access of digital content is being prevented by im- plementing encryption technologies. However, it does not prevent an authorized user from illegally replicating the decrypted content. Hence, encryption alone does not ad- dress all the IP issues related to DRM. Digital watermarking is one of the key tech- nologies that can be used for establishing ownership rights, tracking usage, ensuring authorized access, preventing illegal replication and facilitating content authentication. Therefore, a two layer protection mechanism utilizing both watermarking and encryp- tion is needed [3]. G. Das and V.P.Gulati (Eds.): CIT 2004, LNCS 3356, pp. 344–353, 2004. c  Springer-Verlag Berlin Heidelberg 2004