The Research On Selective Encryption Algorithms For H.264/HEVC Video

With the rapid development of network technology,video business such as online video,video conferencing and video surveillance are emerged.In order to ensure the security of video during the transmission and storage,video encryption was proposed to meet these needs.Video data has the features of huge volume,high real-time requirements and special coding structure.If the traditional complete encryption algorithm is directly used for video data,it is difficult to fulfill the requirements of real-time and operability,etc.H.264 and HEVC,as the most popular and latest video coding standards,respectively,the research of selective encryption algorithm for them has great significance and broad application prospect.In this thesis,the state-of-art of selective video encryption for H.264 and HEVC are first introduced,and then the basic framework and key technologies of H.264 and HEVC are presented.Finally,two selective encryption schemes are proposed.The main works of this paper are as follow:(1)A selective encryption scheme for H.264 is proposed based on chaos and quantization.Firstly,a novel key generation method is constructed,which the encryption key is generated based on the intertwining logistic map.After that,by analyzing the method of encrypting the sign of trailing ones and inter-macroblock nonzero coefficients,the sign of intra-macroblock nonzero coefficients is encrypted,where the encryption of the sign of trailing ones depends on a quantization parameter.Meanwhile,the intra prediction modes,reference frame indices and the sign of motion vector difference are encrypted to protect the texture and motion information of video.Experimental results and analysis show that the proposed scheme has good perceptual security,and can effectively resist different security attacks.Besides,its computational complexity is low,and it can achieve a good trade-off between security and efficiency.(2)A selective encryption scheme for HEVC based on sign data hiding is put forward.In the scheme,not only the encoded sign of intra-CU nonzero coefficients are encrypted,but also the hidden sign of the first intra-CU nonzero coefficient are encrypted.Besides,motion merge indices,motion vector prediction indices,sign of motion vector difference and reference frame indices are further encrypted bycontrolling factor in order to protect video motion information.Experimental results and analysis show that the proposed scheme has a good performance in compression efficiency,computational complexity and security,etc.(3)A selective video encryption system is designed and implemented for H.264/HEVC.It will provide a experimental test platform for the further research on video encryption algorithm.The proposed encryption methods can effectively protect the content of H.264 and HEVC video.It can be widely applied in the video conferencing and video surveillance applications and so on.