Flexible Macroblock Ordering Scramble Encryption Techniques for H.264/AVC Videos

In this paper, a new video encryption method through scrambling the compressed videos is presented, which is targeted for H.264/AVC video encryptionin order to provide the greatest content protection in the compressed domain.The proposed algorithm uses a macroblock switching mechanism to scramble the video contentfor the compressed video sequences. Only the instantaneous decoded reference (IDR) pictures are scrambled to take the advantage of drift error propagation from all the inter-prediction frames. The proposed encryption technique is designed to perform after the encoding process on the compressed bitstream such that bitstream is modified by the parser directly. Finally,the scrambled video is still format-compliant to a general H.264/AVC decoder and can only be recovered by the authorized user that owns private key. Based on experimental results, the scene in the scrambled video can be effectively protected by the proposed scheme with low computational complexity and negligiblebitrate overhead.