Résumé
This paper presents a traitor tracing method dedicated to video content distribution. It is based on a probabilistic traitor tracing code and an orthogonal zero-bit informed watermark. We use the well-known Tardos fingerprinting tracing function to reduce the search space of suspicious users. Their guiltiness is then confirmed by detecting the presence of a personal watermark embedded with a personal key. To prevent watermarking key storage at the distributor side, we use a part of the user probabilistic fingerprinting sequence as a personal embedding key. This method ensures a global lower false alarm probability compared to original probabilistic codes. Indeed, we combine the false alarm probability of the code with the false alarm probability of the watermarking scheme. However the efficiency of this algorithm strongly depends on the number of colluders at the watermarking side. To increase the robustness, we present an additive correlation method based on successive watermarked images, we then study its limitation under different sizes of collusion.