A scalable video scrambling method in MPEG compressed domain

This paper proposes a scalable video scrambling method in MPEG domain. Scrambling strength could be controlled to produce video with distortion level ranging from insignificant to significant. AC components in each coefficient block are first scalably transformed according to desired level of distortions. Then, all pairs of the length of zero-run and the level of non-zero component are locally shuffled in each coefficient block. Furthermore, all coefficient blocks are globally shuffled within a region to be scrambled. The scrambled video stream could be descrambled to restore the original video with a right key. The basic performance of this method is verified through computer simulations.