中文摘要：

由于图像隐写所引起的各种统计特征变化是不确定的,文中将Vague集相似度量引入隐写系统的安全性评价中.从图像的一阶统计特征和二阶统计特征两方面,定义了基于载体数据及载密数据相关Vague集相似度量的隐写系统一阶和二阶安全性测度,证明了该安全性测度的有界性,对称性和一致性.在假设图像满足独立同分布的条件下,证明了所提出的两种安全性测度是等价的.结果表明,所提出的二阶安全性比一阶安全性能更好地反映隐写引起的载体统计分布变化.与确定模式下的安全性测度相比,当嵌入率低于0.5比特/像素,新的测度可更好地度量隐写系统安全性,因此该测度对小容量的隐写及隐写分析算法设计具有更好的指导作用.

英文摘要：

Since variations of statistical features caused by image steganography are indeterministic,vague set similarity measure is introduced to steganographic system for security evaluation in this paper.The first-order and the second-order security measure based on vague set similarity measure are defined to measure the similarity between cover images and stego images in the sense of the first-order and the second-order image statistical feature,respectively.The newly defined security measures are then proved to have the properties of boundedness,symmetry and unity.Finally,under the assumption that the pixels＇ statistical distribution is identically independent distributed,the first-order and the second-order security measure are proved to be equivalent.Simulation results show that the second-order security measure can always capture more obvious statistical changes than the first-order security measure.In addition,compared with the security measure defined under a deterministic image statistical distribution model,the newly defined security measure is more sensitive when the embedding rate is lower than 0.5 bit per pixel,thus providing better guidance for the design of steganography and steganalysis with a small embedding rate.