Highly Secure and Fast Video Encryption Using Minimum Overhead in H.264/AVC Bitstream

Abstract

Abstract This paper primarily focuses on the encryption method used to design a selective video encryption scheme to meet following objectives. Encryption and decryption are able to secure in bits-level cryptographic security (after encryption), as well as in the pixel-level visual content security (after decoding for unauthorized user) to meet with sensitive video applications with minimum encryption overhead. It provides perceptual encryption with total scrambling of visual content. Besides, it also makes provision for randomness, not only in spatial but also in the temporal domain. It is presumed that an overall encryption and decryption scheme is quick enough to meet real-time applications. There is no change in the quality of video for genuine users. However, these objectives have been achieved in our proposed algorithm in expense of slight changes in compression bandwidth. The proposed algorithm encrypts residue data and motion vectors after entropy encoding to scramble spatial and temporal resolution. Encryption of motion vectors is based on Expo-Golomb entropy coding in inter-coded macroblock and DC value of residues is encrypted based on context-adaptive variable-length coding (CAVLC) in intra-coded macroblock. In addition, encryption is carried out using an advanced encryption system (AES) in a counter mode stream cipher. The paper deals with security analysis of a proposed scheme in terms of cryptography, as well as perception security.