Motion Compensation Techniques in Permutation-Based Video Encryption

This paper presents a motion compensation technique applied in the permutation-based digital video encryption and compression method introduced by Socek et al. The encryption method is based in permutations that can improve the spatial correlation on each video frame, making them more compressible by a spatial encoder. However, the compression performance of this method depends on the temporal correlation between consecutive frames and the algorithm does not provide a way to explore non-trivial temporal correlation properly. Consequently, the compression ratio of an encrypted video is very sensitive to the motion in the scene. Here, we propose a motion compensation method to be applied in both encryption and decryption process. Experiments using the H.264 codec show a significant improvement of the compression performance in high motion video sequences.