A novel copyright protection for digital images using extra scrambled information

Both watermarking and fingerprinting techniques can be used for protecting digital contents with different properties. A watermarking system may degrade the fidelity of the digital contents by embedding watermark messages, while a fingerprinting system may have high computational complexity to generate unique features for digital contents. In this paper, we propose a novel copyright protection technique that combines positive features of both techniques. The proposed technique can distribute digital images without embedding messages related with them, and save extra scrambled information on simple fingerprints stored in a certified database. Experimental results show that the proposed method outperforms an existing method for various signal processing attacks. The proposed technique is also flexible and fast so that it can be used for real-time applications.