Collusion Secure Convolutional Spread Spectrum Fingerprinting

摘要

Digital Fingerprinting is a technique for the merchant who can embed unique buyer identity marks into digital media copy and also makes it possible to identify 'traitors' who redistribute their illegal copies. This paper first discusses the collusion-resistant properties of spread-spectrum sequence against malicious attacks such as collusion combination, collusion average and additive noise. A novel two-layers secure fingerprinting scheme is then presented by concatenating the spread-spectrum code with a convolutional code. Moreover, Viterbi algorithm is improved by using Optional Code Set. The code length, collusion security and performance are proved and analyzed. As the results, the proposed scheme for perceptual media has shorter fingerprinting length and achieves optimal traitor searching.