为了使数字水印算法具有更好的鲁棒性,首先阐述了迭代函数系(iterated function system,IFS)理论,并给出了构造IFS吸引子的随机迭代算法;然后从理论分析了IFS吸引子抗几何失真的特性,并提出了一种非对称数字水印算法;接着利用三点法将数字水印信息转化为IFS码,并由重构的分形水印图像与原始图像进行相关性处理得到索引集;最后版权者和第3信任方用私钥将索引集进行数字签名和加盖时间戳。水印检测时,只需利用第3信任方和版权者的公钥,而不需要原始图像参与。实验结果表明,该算法对噪声
The Craft of System Security by Sean Smith; John Marchesini List of Figures 1.1 An access control matrix 7 1.2 Security and state spaces 10 2.1 Example clearance order 26 2.2 Example categories order 27 2.3 Example MLS lattice 28 2.4 The *-Property
Contents Preface to the Third Edition, vii Preface to the Second Edition, ix Preface to the First Edition, xi Preliminaries, 1 Part 1: Preliminaries, 1 Part 2: Algebraic Structures, 17 Part I---Basic Linear Algebra, 33 1 Vector Spaces, 35 Vector Spa
A NEW INTRODUCTION TO MODAL LOGIC Preface ix Part One: Basic Modal Propositional Logic 1 The Basic Notions 3 The language of PC C) Interpretation D) Further operators F) Interpretation of A , D and s G) Validity (8) Testing for validity: (i) the tru
we construct a discrete-domain multiresolution and multidirection expansion using nonseparable filter banks, in much the same way that wavelets were derived from filter banks. This construction results in a flexible multiresolution, local, and direc
The limitations of commonly used separable extensions of one-dimensional transforms, such as the Fourier and wavelet transforms, in capturing the geometry of image edges are well known. In this paper, we pursue a “true” twodimensional transform that