基于置乱和灰度扩散的图象置乱算法研究

Study on Image Hashing Based on Hashingand Grey Degree Spreading Algorithm

置乱和灰度扩散是置乱图象的两种手段,其目的都是达到图象的不可认识.作者重点研究扩散算法,提出了传递扩散与局域扩散的概念,并详细分析了传递扩散算法在受到干扰或攻击时所引起的图象失真性.在此基础上,提出了局域单点扩散概念,产生了单点扩散与置乱相结合的图象置乱算法.实验证明,该算法具有很好的置乱效果和较高的鲁棒性,可广泛应用于数字图象的置乱操作.

Hashing and spreading, which aim are to make image become unrecognizable, are two kinds of methods of hashing image. Spreading algorithm is mainly studied, and the concepts of transfer spreading and local spreading are proposed. The distortions, which are caused when transfer spreading algorithms are attacked or interfered, are analyzed in detail. On the basis of this, the concept of local single point spreading is introduced and the image hashing algorithm combining into single point spreading and hashing has been also generated. Meanwhile, the algorithm are shown by experiments that it has excellent hashing performances and robustness and can be extensively applied in hashing of digital image.