資源描述:
《基于波原子變換的語音信號去噪畢業(yè)論文》由會員上傳分享,免費在線閱讀,更多相關(guān)內(nèi)容在學(xué)術(shù)論文-天天文庫。
1、Contents1.INTRODUCTION12.WAVEATOMTRANSFORM42.1DefinitionofWaveAtomTransform42.21-DCharacteristicsinWaveAtomTransform62.3TheStructureof1-Dfilter-bankinWaveAtom……………………………….…103.THRESHOLDINGMETHODFORNOISEREDUCTION173.1HardandSoftThresholdings173.2DeterminationofThreshold204.
2、EXPERIMENTSANDDISCUSSIONS……………………………………………..274.1ExperimentalConditions…………………………………………………………..274.2ResultsandDiscussions285.CONCLUSION37REFERENCE38ABSTRACT(INKOREAN)40i401.INTRODUCTIONSpeechisoneofthemostnaturalandconvenientwaysofintercommunication.Thus,speechsignalproces
3、singtechniquesforaman-machineinterfacelikespeechrecognition,speechsynthesisandspeechcodinghavedrawnmuchattention.Asspeechprocessingmovedfromthelaboratorytothefield,ithasbecomeincreasinglyimportanttodealwiththeambientnoise.Sincethequalityandintelligibilityaredegradedbytheam
4、bientnoise,theproblemofreducingnoisecomponentsofthenoisyspeechisstillregardedasanimportantissueinthefieldofspeechresearch[1-3].Mostclassicalmethodsforhandlingambientwidebandnoisewerevariantsofanapproachbasedonsubtractinganestimateofthespectrumofthenoisefromthatofthenoisysp
5、eech[4-7].AndthenanovelapproachfornoisereductionusingthewavelettransformhasbeenproposedbyD.L.Donoho[8].ItemploysthethresholdingtechniqueinthewaveletdomainandhasshowntohavegoodpropertiesforawideclassofsignalscorruptedbyadditivewhiteGaussiannoise.Overthepasttwodecades,numero
6、ussignalprocessingtechniqueswiththewavelettransformhavebeendevelopedtomakeuseofitssuperioritytotheconventionalFouriertransform.Recently,waveatomtransformhasbeenproposed,andhasshownits40potentialindenoisingexperimentsonbothseismicandfingerprintimages[1].Waveatomwasintroduce
7、dasavariantof2Dwaveletpacketsobeyingtheparabolicscaling.Inanutshell,waveatomsinterpolateexactlybetweendirectionalwaveletsandGabor,inthesensethattheperiodofoscillationsofeachwavepacket(wavelength)islinkedtothesizeoftheessentialsupport(diameter)bytheparabolicscaling,i.e.,wav
8、elength~(diameter)2[1,2].Inthisthesis,weapplythe1Dwaveatomtransformtonoisyspeechsignalsfo