Mixed-strategy Nash equilibrium in the camera source identification game

Although sensor pattern noise (SPN) is recognized as a reliable device fingerprint for camera source identification (CSI), this fingerprint could have been forged by anti-forensics. In order to evaluate the performance in the case of both forensic investigator and forger exist, we model this interplay as a camera source identification game. The mixed-strategy Nash equilibrium is introduced to solve this game. The Nash equilibrium receiver operating characteristic (ROC) curves are obtained experimentally. Through our analysis, we are able to determine under which case the CSI result is reliable.