Complaint Selective encryption for H.264/AVC video streams

This paper presents a novel selective encryption scheme that allows for secure transmission of video streams such as H.264/AVC ones, while keeping complete backward compatibility with the corresponding video standard. This compatibility allows consequently any standard compliant decoder to decode the ciphered stream without specific provision in terms of resynchronization procedure, albeit incorrectly from the visual point of view. The bits to be encrypted are chosen with respect to the video standard, the full compatibility being achieved by encrypting bits for which the impact of each of the encrypted configurations gives a non-desynchronized and fully standard compliant bitstream. Numerical results obtained with this partial ciphering algorithm in the context of H.264/AVC show that PSNR degradations of about 25 to 30 dB are obtained when the ciphering key is unknown