对QIM水印滤波攻击的估计  

Estimation for filtering attacks on QIM watermarks

作　　者：王津申[1] 戴跃伟[1] 王执铨[1] 

机构地区：[1]南京理工大学自动化学院,江苏南京210094

出　　处：《通信学报》2007年第6期90-95,共6页Journal on Communications

基　　金：国家自然科学基金资助项目(60374066)~~

摘　　要：提出一种基于量化水印的两频带幅值比例攻击的估计算法。基于量化的水印算法对线性时不变(LTI)滤波攻击没有顽健性。考虑一种使用滤波器组调整信号频谱的多频带幅值比例攻击。首先,给出受攻击信号的概率密度函数(PDF)模型。然后,使用这个PDF模型,给出两频带滤波攻击幅值比例因子的最大似然估计方法。最后,以合成的音频信号进行实验,结果显示出所提出的估计技术的有效性。A scheme for estimating two-band amplitude scale attack within a quantization-based watermarking context was presented. Quantization-based watermarking schemes are not robust against linear time invariant （LTI） filtering attacks, on which a multi-band amplitude scaling attack that modifies the spectrum of the signal using an analysis/synthesis filter bank was concentrated. First the probability density function （PDF） of the attacked signal was derived. Second, using a simplified approximation of the PDF model, a maximum likelihood （ML） procedure for estimating two-band amplitude scaling factor was proposed. Finally, experiments were performed with synthetic audio signals showing the good performance of the proposed estimation technique under realistic conditions.

关 键 词：水印 最大似然估计 多频带 

分 类 号：TP309[自动化与计算机技术—计算机系统结构]