1.2ks語音編碼技術的研究

1、北京郵電大學碩士學位論文1.2ks語音編碼技術的研究姓名：胡安勇申請學位級別：碩士專業(yè)：信號與信息處理指導教師：趙振綱20040222些室塑塾苧蘭堡主莖壘墮圭————————————笪RESEARCHON12K蟊恁SPEECHCODINGABS薯RACTSpeechisanimportantwayinnormalcommunicationandisoneofthemostsignificantinformafionmediaSpeech

2、compressionisbecomingincreasinglyimportantnotonlyintheaspectofspeechstoragebutalsointheeraofdigitalcommunicationsItisimportantintheefforttomakemoreemcientuseofthechannelandteduce拯ememoryrequirements。Duetobandlimit、lowbit

3、—ratecoderhasawideapplicationinmilitarycommunicationInordertoreducetherateofthespeechcodingandimprovethequalityofsynthesizedspeech。severalcarefulresearchandmanyexperimentsontheaspectso’speechanalysis，parametercode，decode

4、andspeechsynthesishavebeencarriedoutbasedOilMBE(MultiBandExcitation)algorithmafterbrieflyreviewingseveralkindsofexistingmethodsofspeechcodingandtlleirlimitatiOnSA12kb／sMBELPCfMultiBandExcitationLinearPredictionCoding)spe

5、echcodingalgorithmwithClanguageemulatorhasbeenobtained。FundamentalfrequencyiSthemostimportantparameterinMBELPCspeechmedelToobtainaccuratepitchestimateandguaranteethecontinuityofpitchtrackerandpreventsmoothingouttheabrupt

6、pitchchanges，anovelpitchtrackingalgorithmusingdynamicprogrammingaccordingtothefirst5localminimalpeaksoferrorfunctionisproposedinthisthesisThemaindi蕊cultyofreducingbitrateofMBELPCalgorithmiiesine硒cientquantizationofthespe

7、ctralamplitudevectorThebitrateCanbereducedgreatlybyusingLPCtechniqueLinearinterpolationinthelogspectralaccordingtotheharmonicmagnitudesandtheLinearSpectralPairsubstitutesfortheLPCparametersisusedtOcompensatetheLPCmodelin