Commutative Encryption and Data Hiding in HEVC Video Compression

In this paper, an efficient commutative encryption and data hiding scheme for HEVC videos is proposed. The commutative property allows ciphering a steganographic video without interfering with the embedded signal or to perform steganography on an encrypted video while still allowing perfect decryption. The syntax elements in the HEVC standard, including the sign of quantized transform coefficient (QTC), the sign of motion vector difference (MVD), and the intra-prediction mode (IPM) are encrypted, which distorts video content greatly and thus keeps perception security. Data embedding employs a specific QTC modification method, which makes the visual distortion caused by data hiding very low. Furthermore, the proposed framework will produce an HEVC format compliant bitstream and permits the hidden information to be extracted either in the encrypted domain or in the decrypted domain. Several benchmark video sequences of different resolutions and diverse contents are used for experimental evaluation.