基于宏块编码信息自适应置换的H.264/AVC视频加密方法  

H.264/AVC Video Encryption Based on Adaptive Permutation of Macroblock Coding Information

作　　者：梁剑 何军辉[1] LIANG Jian;HE Jun-hui(School of Computer Science and Engineering,South China University of Technology,Guangzhou 510006,China)

机构地区：[1]华南理工大学计算机科学与工程学院,广州510006

出　　处：《计算机科学》2022年第1期314-320,共7页Computer Science

基　　金：广东省自然科学基金(2019A1515011231)。

摘　　要：云存储的发展使人们愿意将个人视频数据传输至云端,但伴随而来的数据安全问题日益突出,选择加密是对视频进行隐私保护的有效手段之一。针对目前H.264/AVC视频选择加密方法普遍存在安全性不足的问题,文中提出了一种基于宏块编码信息自适应置换的H.264/AVC视频加密方法。该方法根据宏块的编码类型逐帧自适应生成伪随机序列,利用伪随机序列将宏块编码信息中的残差编码方案(Coded Block Pattern, CBP)和残差数据(Residual)在宏块间进行随机置换,同时还对Ⅰ宏块的帧内预测模式以及P宏块与B宏块的运动向量差值的符号进行加密。实验结果表明,该方法可保证加密视频兼容H.264/AVC编码标准,并具有加密空间大、密钥敏感性好、视频码率变化小的特点。与现有的主流加密方案相比,所提方法在视觉安全性和抵抗最新提出的轮廓攻击方面表现更佳。The development of cloud storage makes people willing to upload personal video to the cloud,but the data security problems brought by it have become increasingly prominent,selective encryption is one of the effective ways to protect video privacy.Aiming at the problem of insufficient security in the current H.264/AVC video selective encryption method,a novel H.264/AVC video selective encryption method based on adaptive permutation of macroblock coding information is proposed.The method adaptively generates pseudo-random sequence frame by frame according to the macroblock types,uses the pseudo-random sequence to randomly permute the coded block pattern(CBP)and the residual data in the coding information of a macroblock between macroblocks,changes the intra prediction modes of I macroblocks,and flips the signs of motion vector differences of P macroblocks and B macroblocks.Experimental results show that the proposed method can preserve format compatibility with H.264/AVC coding standard,and has characteristics of large encryption space,good key sensitivity,and small video bitrate variation.Compared with the existing encryption schemes,the proposed method performs better in terms of visual security and resistance to state of the art of sketch attack.

关 键 词：云服务 H.264/AVC 选择加密 编码信息 自适应置换 

分 类 号：TP309[自动化与计算机技术—计算机系统结构]