An Efficient Commutative Encryption and Data Hiding Scheme for HEVC Video

In this paper, an improved commutative encryption and data hiding scheme for bit rate preservation of High Efficiency Video Coding (HEVC) is proposed. To achieve commutative property, one set of syntax elements within the HEVC standard is utilized for data hiding, while another set is exploited for encryption. Specifically, the syntax elements including the sign of quantized transform coefficient (QTC), the sign of motion vector difference (MVD), and the magnitude of MVD are encrypted to perceptually distort the video. On the other hand, an improved QTC modification method is employed for data hiding to increase the embedding capacity. The proposed framework produces the format compliant bitstream and allows the hidden information to be extracted regardless of the video being in the encrypted or decrypted from. Experimental results demonstrate that the proposed scheme keeps the bit rate unchanged while increasing the embedding capacity.