论文部分内容阅读
已有的大多数H.264加密算法只考虑了视频编码的特性,而忽略了人眼才是处理视频信号的接收端.提出一种基于人眼视觉感知特性的运动注意力的视频熵编码加密算法.将所有宏块根据视觉感知注意力模型分成I帧宏块、中心区域宏块、注意力较大宏块和注意力较小宏块.采用混沌系统产生加密密钥,然后对四类宏块采用不同的加密手段,先对I帧宏块DCT系数翻转然后进行熵编码加密,然后引入标示宏块在人眼中注意力强弱的视觉注意力权重分布w:当wij=1时,宏块处于中心区域,对MV值、DCT系数的熵编码过程加密;当wij≠1时,则计算宏块运动量的加权,并与阈值T比较.注意力较大宏块进行熵编码加密,注意力较小宏块则不做加密操作.本文算法将感知模型引入加密算法中,在同一帧内实现分类的加密手段.实验表明,本算法加密后数据量仅增加了10%-15%,加密所占用额外时间较小,基本对信噪比SNR没有造成影响,从直方图和混淆后的图形分析,加密的效果显著.
Most of the existing H.264 encryption algorithms only consider the characteristics of video coding, while ignoring the human eye is the receiving end of the video signal.An eye-based visual perception of motion-aware video entropy coding encryption Algorithm.All macroblocks were divided into I-frame macroblocks, central-region macroblocks, attention-intensive macroblocks and attention-less macroblocks according to the visual perception model.An encryption key was generated by the chaotic system, and then the four types of macros Block using different encryption means, the I-frame macroblock DCT coefficients first flip and then entropy encoding and encryption, and then introduced into the macro-block in the human eye attention visual attention weight distribution w: wij = 1, macroblock In the central region, the entropy encoding process of MV value and DCT coefficient is encrypted, and when wij ≠ 1, the weight of the motion amount of the macroblock is calculated and compared with the threshold value T. The macrofocus with larger attention value is encrypted by entropy coding, Small macroblocks do not do encryption operation.In this paper, the perceptual model is introduced into the encryption algorithm to realize classification in the same frame.Experiments show that the amount of data encrypted by this algorithm only increases by 10% -15% Extra time is small, This does not affect the signal to noise ratio SNR, graphical analysis from the histogram and confusion, encryption effect is remarkable.