基于语音编码中自适应码本的隐藏信息方法  

Steganographic method in self-adaptive codebooks of speech codec

作　　者：杨婉霞[1,2] 孙东红[2] 黄永峰[2] 

机构地区：[1]甘肃农业大学工学院,甘肃兰州730070 [2]清华大学信息科学技术学院,北京100084

出　　处：《计算机工程与设计》2013年第8期2656-2661,共6页Computer Engineering and Design

基　　金：国家自然科学基金项目(61271392);国家863高技术研究发展计划基金项目(2011AA010704)

摘　　要：为了解决低速率语音编码的信息隐藏问题,选择了目前广泛使用的低速率语音编码(iLBC)为研究对象,提出了一种在语音编码过程中嵌入机密信息的方法,设计了一种基于iLBC语音编码的动态码本量化过程的信息隐藏算法。该方法利用低速率语音编码中自适应码本的动态构建特点,并结合QIM原理来实现信息隐藏,较传统基于静态码本的QIM方法具有更好的对抗统计分析检测能力,同时具有较好的隐蔽容量。实验结果表明该隐藏算法在13.3Kbps的载体速率下能获得450bpS隐藏容量,而且载密信息的语音质量的PESQ值下降不到7%,具有很好的隐蔽性能。In order to solve information hiding problem in low bit rate speech coding,taking the low bit rate speech coding as the steganographic carrier and the widely used iLBC as the research subject,a kind of information hiding method is proposed by which confidential information is embedded within the speech coding process,and then a steganographic algorithm is designed which is based on the quantization process of the dynamic codebook of iLBC speech codes.Information hiding is initiatively achieved via QIM axiom by utilizing the property of dynamic composing of the self-adaptive codebooks of the low bit rate speech coding.Tests show that the method is of higher deficiency concerning the anti-testing of statistical analysis and has a better performance in imperceptibility compared with the traditional QIM method which is based on static codebook.According to the relative experiments,up to 450 bps steganographic capacity is achieved within 13.3 Kbps carrier rate while the loss of PESQ value of speech quality with steganographic information is less than 7%,which shows a superb performance of imperceptibility.

关 键 词：语音编码 隐藏载体 信息隐藏 压缩域 隐藏容量 隐蔽性 

分 类 号：TP391.4[自动化与计算机技术—计算机应用技术]