A multi-layer key stream based approach for joint encryption and compression of H.264 video

Encryption of multimedia video data has been extensively studied. However, a pipelined method of compression followed by encryption is not always feasible and springs new challenges, namely the effect of visual degradation and the computational cost of the encryption process. Recently, joint encryption and compression techniques, which aim to encrypt the video as it is being compressed by the encoder, have gained popularity. This work aims to develop a lightweight yet effective multi-layer key stream based technique to encrypt video data by performing joint encryption and compression. Our joint encryptor-encoder performs almost as fast as a normal H.264 compression-only encoder. The multi-layer key stream we use for encryption is extracted from the underlying video structure itself, thus thwarting (piracy) key generators. It also facilitates efficient handing of packet loss in real-time transmission. Results show our method produces almost complete obscuration of the video, a consistent degradation for diverse scenes, and format compliant encrypted H.264 video.