离散余弦变换域隐藏算法隐藏容量与频域系数选择研究

摘要

Hiding capacity, robustness and invisibility are some of the key parameters in information hiding system.Moreover, these parameters are seriously impacted by the difference of Discrete Cosine Transform (DCT) coefficients in DCT domain hiding algorithm.Embedded capacity, which is impacted by the mutual interference of visual perception of different DCT coefficients and the reverse DCT, was analyzed in this paper.Furthermore, the relation between hiding capacity and coefficients-chosen was given out in DCT domain hiding algorithm.A conclusion that there is no correlation between embedded position and robustness against compression of embedded information was put forward, and embedded capacity could be improved in reference to this conclusion.The experimental results show that this conclusion is correct even if the system is disturbed by noise%隐藏容量、不可感知性和鲁棒性是信息隐藏系统的几个关键性指标,选择不同的离散余弦变换(DCT)系数对DCT域隐藏算法的这些指标影响很大.分析了不同DCT系数的视觉感知特性和DCT逆变换的相互干扰性对嵌入容量的影响,并给出了DCT域隐藏算法隐藏容量与所选择的系数之间的关系.通过分析JPEG压缩不变性给出了嵌入信息抗压缩的鲁棒性与嵌入位置无关的结论,可为提高嵌入容量提供参考.仿真实验结果有效地支持了理论分析所得出的结论,实验还证明在有噪声干扰下这一结论仍然成立.