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265()Vol.26No.5200610JournalofNanjingUniversityofPostsandTelecommunications(NaturalScience)Oct.2006:167325439(2006)0520022205LPC,,,210003:LPC(LinearPredictionCoding)LPC,LPCLPC,ARMA,,LPC,,,:;LPC;;:TN312.3:AANewMethodforApproachingSpeechExcitingPulseBasedonLPCResidualDENGZong2yuan,GAOYin2qiu,YANGZhenInstituteofSignalandInformationProcessing,NanjingUniversityofPostsandTelecommunications,Nanjing210003,ChinaAbstract:ThispaperproposesanovelalgorithmtoovercomethedisadvantageofLPC(LinearPredictionCod2ing).Firstlyweanalyzethespeechwithreversedpolarityandpresenttheideaofpost2filteringoftheLPCresidualofthesevoicedspeechframes.TheproposedalgorithmreducescomputationalcomplexityofARMA(AutoregressiveMovingAverage)modelandtheeffectofpole2pointsinglottismodel.Experimentalresultsshowthatthisnewalgo2rithmobviouslyimprovestheperformanceofLPC.Finally,wedescribetheusageofthismethodinaudioinforma2tionhiding.Keywords:SpeechSignalProcessing;LPCresidual;First2orderFiltering;InformationHiding:2006201228;:2006205217:(BK2004150)1,,,LPC(LinearPredictionCoding),S.Sakaguchi[1],LPC:,,,,(180),,;LPC,LPC,LPC(),[2],LPC,5%LPC,,11LPC(),LPC(),LPC100%,,,(5%)LPC,LPC,ARMA(AutoregressiveMovingAverageModel),,LPC,22.1LPCLPCs(n)=pi=1ais(n-i)+Gu(n)(1),s(n),u(n),ai,G;p^s(n)=pi=1ais(n-i)(2)e(n)=s(n)-^s(n)=s(n)-pi=1ais(n-i)(3)(1),e(n)=Gu(n),p,e(n),e(n)[3](2),,G(z)u(n),,(),LPCu(n),S.Sakaguchi[2],5%(1)LPC()22.2LPCLPC,,,,,LPC,(3),LPC,,325:LPC3()()LPC,2.3LPC[2],p,LPC,4412,16,20LPC,H(z)=S(z)U(z)=G1-pi=1aiz-1(G)(4):H(z)=S(z)U(z)=G1-pi=1aiz-i1(1-e-CTz-1)2=H1(z)H2(z)(5),H1(z)=G1-pi=1aiz-i,H2(z)=1(1-e-CTz-1)2,C,T,G,H1(z),H2(z),MSE(MeanSquareError)H1(z),LPCH2(z)Rosenberg[3]:h2(n)=0.5[1-cos(n/N1)]0nN1cos[(n-N1)/2N2]N1nN1+N20other(6),N1,50%,N2,35%,LPCe(n)=s(n)-pi=1ais(n-i)(7)[3]:R(z)=R0(1-z-1)(8),R0(8),((5)),,(7),,LPCe(n),4,ZE(z)=R(z)H2(z)U(z)=1-z-1(1-e-CTz-1)2U(z)(9),C,T,e(n)u(n),ARMA,,,[4]e(n),(9)e(n)u(n)42()2006e(n)=e(n)-ae(n-1)(10)E(z)=(1-z-1)(1-az-1)(1-e-CTz-1)2U(z)(11)a,e(n)u(n),a0.94LPC,,,,LPC,,H1(z),H2(z),LPCH1(z)H2(z),H2(z)H1(z),,,H1(z)=H1(z)H2(z)=H2(z),(),;,H2(z)=H2(z)=1-0195z-1,H1(z)H1(z),H1(z)H1(z)MSE,MSE,LPCH1(z)H1(z),,LPC,LPC(5),,,,,,,53,8kHz,40dB4P=12LPC,(9),a=0.94()6,,,,,,,[5]6LPC,LPC(5%),,,,7LPC(7),,(7)LPC(7),[1]7LPC525:LPC4,5%LPCARMA,,LPC,LPCLPC,LPC,,:[1]SAKAGUCHIS,ARAIT,MURAHARAY.TheEffectOfPolarityInversionofSpeechonHumanPerceptionandDataHidingAsanApplication[C]//Proceedingsof2000IEEEInternationalConfer2enceonAcoustics,Speech,andSignalProcessing.2000,2(5-9):917-920.[2].[D].:,2005.[3].[M].:,2002.[4],.[M].:,1995.[5]ALEXANDERST.Asimplenoniterativespeechexcitationalgo2rithmusingtheLPCresidual[J].IEEETransonAcoustics,SpeechandSigalProcessing,1985,33(2):432-434.[6].[M].:,2000.:(1983-),,,(1982-),,(1961-),,,,1988,1999,19921993Bremen62()2006