The Research And Realization Of Video Encryption Algorithm Based On H.265

With the development of multimedia and internet technology rapidly,a serious video coding standards from H.261 to H.264 are proposed,which are used in many aspects related to video,such as digital television,network VOD system,video conference,video surveillance,medical imaging and digital photography.However,there is a problem that the video contents are stolen illegally and destroyed willfully,which has a great threat to people's life and country's stabilization.Therefore,it is significant to protect video contents in many aspectsNowadays,many researchers propose encryption algorithms for protecting video contents.They make a lot of contributions to video information safety.However,there are some problems in proposed encryption algorithms.For example,encryption space of algorithms based on sign encryption in coding process is so small that encryption systems and video contents are not safe.It is difficult to keep the format compliance in entropy coding stage based on CABAC.It is not practical in this case.Encryption schemes based on syntax elements before entropy coding stage affect coding efficiency due to the property of source coding being disturbed.It cannot satisfy demands of technology for H.264 video coding standard with the development of HD(High-definition)and Ultra HD video.This paper proposes a selection encryption algorithm based on H.265/HEVC standard.The paper aims to get a balance for video safety,video coding performance and format compliance in encryption process.Related works are as follows:1)Video contents are related to coefficients level,which is the encryption object in our scheme.In order to keep coding performance,the entropy coding stage of transform coefficients is selected.In order to keep format compliance,suffix code of truncated Rice code(TR)and kth Exp-Golomb(EGk)code of syntax element coeff_abs_level_remaning in binarization process is used for encryption because bypass encoding mode is adopted and it doesn't affect the property of source entropy coding.Detailed experiment analysis is introduced in algorithm implementation.2)The algorithm above only changes coefficient levels of video contents rather than motion information of moving objects.The joint encryption scheme is proposed that motion information and coefficients levels are all encrypted based on the drawback.Merge mode,a newly motion vector prediction technology in H.265,is encrypted in proposed scheme.It reflects motion information of moving objects.Changing merge index doesn't destroy format compliance and has a less influence on coding performance.The goal is to achieve highly safety of video contents at the less costs of coding performance under format compliance.The paper focuses on the problem that format compliance is destroyed in entropy stage based on CABAC and achieves a good balance between coding performance and video protection under format compliance.