A New Inter-frame Collusion Attack and a Countermeasure

Abstract

One of the challenging issues in video watermarking is its robustness to inter-frame collusion attacks. The Inter-frame collusion attacks exploit the inherent redundancy in the video frames or in the watermark to produce an unwatermarked copy of the video. A basic inter-frame collusion attack is the frame temporal filtering(FTF) attack, where temporal low-pass filtering is applied to the watermarked frames in order to remove temporally uncorrelated watermarks. If the video frames contain moving objects or camera motion, temporal low-pass filtering introduces visually annoying ghosting artifacts in the attacked video. Thus the applicability of the FTF attack is limited only to static scenes. We propose an extended FTF attack which overcomes this limitation by exploiting the motion within the video frames. Experimental results presented in this paper confirm the effectiveness of the proposed attack over the FTF attack. A countermeasure to this extended FTF attack is also presented.