适用于移动通信视频点播的感知加密算法

在视频点播(VOD)应用中,为刺激用户购买高质量的视频版本,往往希望播放的加密视频仍可部分感知,这就是所谓的“感知加密”,因此,需要研究特别的加密算法对视频进行加密。针对目前适用于移动通信视频点播的H.264视频感知加密算法较为缺乏的问题,提出了一种基于祖冲之(ZUC)算法和压缩感知(CS)的视频加密算法。首先利用ZUC构建随机测量矩阵,之后利用测量矩阵对量化后的离散余弦变换(DCT)系数进行测量,并将测量值作为新的量化后的DCT系数进行编码,使新的系数与原始系数不同,从而实现加密。最后定义了良好的感知加密算法应具备的特征。实验结果表明,该算法对视频的压缩码率影响较小,具有较低的时间复杂度,并且算法对密钥变化敏感,有较好的感知安全性。

Perceptual encryption algorithm for mobile communication VOD application

In Video-On-Demand (VOD) applications, it is desired that the encrypted multimedia data are still partially perceptible after encryption in order to stimulate the purchase of the high-quality versions of the multimedia products. This perceptual encryption requires specific algorithms for encrypting the video data. Duo to lack of H.264 video perceptual encryption algorithms for mobile communication application, a video encryption algorithm based on ZU Chongzhi's (ZUC) algorithm and Compressive Sensing (CS) was proposed. First of all, ZUC algorithm was utilized to construct a random measurement matrix. Then the quantified Discrete Cosine Transformation (DCT) coefficients were measured by measurement matrix, and the measured values were regarded as new quantified DCT coefficients to encode, which realized the encryption by using the difference between original and new coefficients. Finally, the characteristics of a good perception encryption algorithm were defined. The experimental results show that the proposed algorithm has little effect on video compression bit rate with low time complexity, and it is also sensitive to key change with good perceptual security.