Duffing振子与分数傅里叶变换的Chirp水印检测性能对比研究  

Comparison between Duffing oscillators and FRFT detector in Chirp typed watermarking detection

作　　者：李东明[1] 王广君[1] 宋麦玲[2] 

机构地区：[1]中国地质大学信息中心,武汉430074 [2]中国地质大学计算机学院,武汉430074

出　　处：《计算机应用研究》2013年第5期1520-1522,1526,共4页Application Research of Computers

基　　金：湖北省自然科学基金资助项目(2011335070);中央高校基金资助项目(CUGL120278)

摘　　要：研究Duffing振子和分数傅里叶变换在Chirp类水印检测中的性能比较。首先分析目前分数傅里叶变换检测Chirp类水印的不足,然后将嵌入在载体低频小波域的非周期Chirp信号通过分块平滑转换为单频周期信号,利用Duffing振子阵列检测器检测微弱的周期信号。实验表明,当信噪比为-41 dB时,Duffing振子仍然能有效检测到水印的存在,此时分数傅里叶变换失效;而当信噪比较高时,分数傅里叶变换计算较Duffing振子检测简单。This paper analyzed the shortcomings of the FRFT detection method, and then changed the Chirp typed watermark which was embedded into the low frequency band of the host image in the wavelet domain into weak single frequency periodic signal which was then detected by the Duffing oscillators. It utilized the model of deterministic signal detection with unknown parameters to formulate the watermark detection. Experiments show that the detector performs effectively when the signal-to- noise ratio is greater than -41 dB, and the FRFT method is simple than Duffing oscillator.

关 键 词：微弱信号检测 数字水印 小波变换 DUFFING振子 CHIRP信号 

分 类 号：TP309[自动化与计算机技术—计算机系统结构]