一种挖掘低速率语音编码最低有效位的新方法  

A NEW METHOD OF MINING LEAST SIGNIFICANT BIT IN LOW BIT-RATE SPEECH CODE

作　　者：吴秋玲[1,2] 吴蒙[2] Wu Qiuling;Wu Meng(College of Zijin,Nanjing University of Science and Technology, Nanjing 2 1 0 0 4 6 , Jiangsu, China;College of Telecommunications and Information Engineering, Nanjing University of Posts and Telecommunications, Nanjing 21 00 0 3 , Jiangsu, China)

机构地区：[1]南京理工大学紫金学院,江苏南京210046 [2]南京邮电大学通信与信息工程学院,江苏南京210003

出　　处：《计算机应用与软件》2016年第8期273-276,共4页Computer Applications and Software

基　　金：江苏省普通高校研究生科研创新计划项目(KYLX_0815);江苏省高校自然科学研究重点项目(10KJA510035)

摘　　要：信息隐藏是保证信息传输安全的重要手段。针对VOIP系统中低速率语音编码在信息隐藏时最低有效位难以确定的问题,利用遗传算法GA(Genetic Algorithm)作为优化工具,以客观的语音质量评价标准和信息隐藏容量为依据构建遗传算法目标函数,提出一种能够挖掘低速率语音编码最低有效位的新方法。以G.729a语音编码为例进行实验测试,测试结果表明,该方法在给定的语音质量下,以隐藏容量最大为目标可以精确搜索到所有最低有效位。最后通过在语音帧的最低有效位上进行机密信息的隐秘传输验证信息隐藏技术的可行性。In fo rm a tio n h id in g is an im po rtan t means to ensure the secu rity o f in fo rm a tio n transm ission. In view o f the d iffic u lty o f locatin gthe least sig n ifica n t b it o f low -rate speech code in V O IP system w hen h id in g in fo rm a tio n , we use genetic a lg o rith m as the o p tim isation tool andcon struct the objective fu n c tio n o f genetic a lgo rithm according to the objective evaluation c rite rio n o f speech q u a lity and the cap acity ofin fo rm a tio n h id in g , as w e ll as propose a new m ethod w h ich can m ine the least sig n ifica n t b it o f low -rate speech code. E xperim enta l tests havebeen carried out on the exam ple o f G. 7 2 9a speech code, test results show th a t the m ethod can accu rate ly determ ine a ll the least sig n ifica n tb its w ith the ob je ct o f m a xim ising the in fo rm a tio n h id in g capacity un d e r the given voice q u a lity . F in a lly the fe a s ib ility o f in fo rm a tio n h id in gtech nique is ve rifie d b y the covert transm ission o f co n fid e n tia l in fo rm a tio n in least sig n ifica n t b it o f speech fram e.

关 键 词：信息隐藏 最低有效位 遗传算法 低速率语音编码 

分 类 号：TP391.4[自动化与计算机技术—计算机应用技术]