Joint Selective Encryption of CAVLC and Signs of Motion Vectors for H.264/AVC

Currently, researchers are orienting their effort to selective encryption in order to protect video sequences against attacks during their transmission over a public channel. The reasons for this trend are of great importance. To reduce video data amount, the video compression chain is essential and to ensure their security, while in transmission, an encryption algorithm is evident. Thus, inserting the encryption module in the video compression chain is better than applying compression and encryption separately in terms of computing time. This paper presents a chaos based encryption method inserted in the H.264 Advanced Video Coding (AVC) used for video conferencing applications. The selective encryption was applied on context adaptive variable length coding (CAVLC) and on the signs of motion vectors. The results were deducted according to the values of peak signal to noise ratio (PSNR), structural similarity (SSIM) and the encryption rate (ER). Combining selective encryption of CAVLC (SE-CAVLC) and motion vector sign encryption (MVSE) are interesting in terms of enhancing the encryption and to damage the visual quality of the decoded video for both Intra and Inter predicted frames.