Hash key-based video encryption scheme for H.264/AVC

An improved H.264/AVC comprehensive video encryption scheme is proposed. In the proposed scheme, the intra-prediction mode, motion vector difference, and quantization coefficients are encrypted. A novel hierarchical key generation method is likewise proposed, in which the encryption keys are generated based on the cryptographic hash function. Generated frame keys are consistent with the corresponding frame serial numbers, which can ensure frame synchronization in the decrypting process when frame loss occurs. This function provides the property that our scheme is secure against some special attacks for video, such as the frame regrouping attack and frame erasure attack. Our method not only avoids the distribution of encryption keys, but also increases the security. Experimental results show that the proposed scheme is efficient in computing, the encryption process does not affect the compression ratio greatly, and the encryption/decryption process hardly affects the video quality.