Anti-Forensics of Multimedia Data and Countermeasures

This chapter focuses on the specific case of anti-forensics of image and video content. It first reviews the anti-forensic techniques proposed in the literature so far. Next, the chapter analyzes one particular example, namely, the antiforensics of JPEG compression fingerprints. It shows how this anti-forensic technique can be detected with anti-forensic countermeasures. It presents a simple and effective anti-forensic technique to eliminate statistical fingerprints of JPEG compression, which is by far the most popular coding tool for images. The chapter now focuses on the JPEG compression technique, and discusses its side effects in terms of visible noise on the tampered image. Finally, it explains how anti-forensic techniques can be evaluated with respect to forensic detectors, and illustrates how the interplay between the forger and the forensic analyst can be cast in a game-theoretical framework.