基于最短欧氏距离替换码元的VoIP隐写算法  

Codeword Replacement Based on Shortest Euclidean Distance for VoIP Steganography

作　　者：孙鑫昊 王开西 SUN Xinhao;WANG Kaixi(School of Computer Science and Technology,Qingdao University,Qingdao,Shandong 266071,China)

机构地区：[1]青岛大学计算机科学技术学院,山东青岛266071

出　　处：《计算机工程与应用》2022年第13期128-134,共7页Computer Engineering and Applications

基　　金：NSFC-通用技术基础研究联合基金(U1536113)。

摘　　要：信息隐藏的首要目标是不被感知,降低修改率是提高不可见性、实现不可感知的有效方法。根据对载体修改越少,隐写越不可被感知的基本原则,提出了一种基于最短欧氏距离替换码元的VoIP隐写方法,通过降低对载体的修改数量,提高隐写效率,达到了在不降低音频质量的前提下提高隐写不可见性的目的。该方法给出隐写单元的定义后,计算隐写单元中对应线性预测编码(linear predictive coding,LPC)值与秘密消息的欧氏距离,用秘密消息替换具有最短距离的LPC值,并将被替换的LPC值所在位置进行标记,使用互补邻节点方法隐写位置信息,实现秘密消息隐藏。对提出的算法进行了性能分析与对比,实验结果表明,该方法具有较高的隐写效率,隐写修改率降低至22.7%,KL散度值表明其安全性较好,PESQ值在4.0以上,表明语音质量较好。Imperceptibility is the primary goal of information hiding technology,reducing the modification rate is an effective way to improve imperceptibility.The codeword replacement based on shortest Euclidean distance for VoIP steganography is proposed based on the principle that the less modification to a cover will achieve the high imperceptibility,which decreases the modification to a cover and improves the steganography efficiency,thus the invisibility of steganography is enhanced without reducing the quality.After a steganography unit is defined,the Euclidean distance between the secret message and the linear predictive coding(LPC)parameters in the unit is calculated,and the LPC parameter with the shortest distance is selected and replaced by the secret message.The complementary neighbor vertex(CNV)method is employed to indicate which LPC parameters are modified.Compared with other methods,the experimental results show that the proposed method has higher steganography efficiency,its steganography modification rate reduce to 22.7%,its KL divergence indicates the better security,and its PESQ exceeds 4.0,which shows good speech quality.

关 键 词：欧氏距离 信息隐藏 码元替换 音频隐写 VoIP隐写 

分 类 号：TP309[自动化与计算机技术—计算机系统结构]