Security and Robustness Constraints for Spread-Spectrum Tardos Fingerprinting

Benjamin Mathon (1, 2) , Patrick Bas (3) , François Cayre (1) , Benoît Macq (2)

1 GIPSA-CICS - GIPSA - Communication Information and Complex Systems
2 TELE - Laboratoire de Télécommunications et Télédétection [Louvain]
3 LAGIS-SI

This paper presents a practical analysis of the impact of robustness and security on Tardos' collusion-secure fingerprinting codes using spread-spectrum watermarking modulations. In this framework, we assume that the coalition has to face an embedding scheme of given security level and consequently has to suffer a probability of wrongly estimating their embedded symbols. We recall the Worst Case Attack associated to this probability, e.g. the optimal attack which minimises the mutual information between the sequence of a colluder and the pirated one. For a given achievable rate of the Tardos' fingerprinting model, we compare the Improved Spread-Spectrum embedding versus a new secure embedding (called rho-Circular Watermarking) considering the AWGN channel. We show that secure embeddings are more immune to decoding errors than non-secure ones while keeping the same fingerprinting capacity.

Domaines: Traitement du signal et de l'image [eess.SP]; Traitement du signal et de l'image [eess.SP]

Benjamin Mathon, Patrick Bas, François Cayre, Benoît Macq. Security and Robustness Constraints for Spread-Spectrum Tardos Fingerprinting. WIFS 2010 - IEEE international Workshop on Information Forensics and Security (WIFS'10), Dec 2010, Seattle, United States. pp.2010. ⟨hal-00541383⟩