RST-resilient video watermarking using scene-based feature extraction

Watermarking for video sequences should consider additional attacks, such as frame averaging, frame-rate change, frame shuffling or collusion attacks, as well as those of still images. Also, since video is a sequence of analogous images, video watermarking is subject to interframe collusion. In order to cope with these attacks, we propose a scene-based temporal watermarking algorithm. In each scene, segmented by scene-change detection schemes, a watermark is embedded temporally to one-dimensional projection vectors of the log-polar map, which is generated from the DFT of a two-dimensional feature matrix. Here, each column vector of the feature matrix represents each frame and consists of radial projections of the DFT of the frame. Inverse mapping from the one-dimensional watermarked vector to the feature matrix has a unique optimal solution, which can be derived by a constrained least-square approach. Through intensive computer simulations, it is shown that the proposed scheme provides robustness against transcoding, including frame-rate change, frame averaging, as well as interframe collusion attacks.