基于模糊贴近度理论的图像置乱效果评价研究

Study on image scrambling degree evaluation based on fuzzy similarity measure theory

提出了应用模糊贴近度理论来构造图像置乱效果评价的新方法。从图像中任意像素与其周围邻域像素之间存在紧密关系角度出发给出了一种模糊集的定义,给出了图像中各像素所对应模糊集及其补集之间的模糊贴近度,最后根据置乱前后图像所有像素所对应的模糊贴近度之和来构造用于图像置乱效果评价的置乱度函数。大量仿真实验及结果分析表明,提出的评价方法是可行的,反映了加密次数与置乱效果之间的关系,其客观评价结果与人的视觉感知基本一致。

The new image scrambling degree evaluation method based on fuzzy approach measure theory is proposed, The fuzzy set of two order neighbor system of image pixel is firstly constructed and its membership is def＇med, then the fuzzy entropy between the fuzzy set of two order neighbor system and its fuzzy complement set is computed, last the evaluation function of image scrambling degree is constructed by means of the fuzzy approach measure of primary image and scrambled image. Experimental results show that the proposed method is effective to describe the relation between the scrambling effect and the number of iterations in the scrambling techniques, which largely consists with human vision. For different images, when some transformation is used, this evaluation method can reflect to some extent the scrambling effects in each scrambling stage.