MATLABFunctionalityforDigitalSpeechProcessing

MATLABSpeechProcessingCodeMATLABGUIImplementations

1Lecture_3_2012

BasicFunctionality readaspeechfile(i.e.,opena.wavspeechfileandreadthespeechsampleintoa

MATLABarray) writeaspeechfile(i.e.,writeaMATLABarrayofspeechsamplesintoa.wav

speechfile) playaMATLABarrayofspeechsamplesasanaudiofile playasequenceofMATLABarraysofspeechsamplesasasequenceofaudiofiles recordaspeechfileintoaMATLABarray plotaspeechfile(MATLABarray)asawaveformusingastripsplotformat plotaspeechfile(MATLABarray)asoneormore4lineplot(s) convertthesamplingrateassociatedwithaspeechfile(MATLABarray)toa

differentsamplingrate highpass filteraspeechfile(MATLABarray)toeliminatehumandlowfrequency

noise plotaframeofspeechanditsassociatedspectrallogmagnitude plotaspectrogramofaspeechfile(MATLABarray) plotmultiplespectrogramsofoneormorespeechfiles(MATLABarrays)

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ReadaSpeechFileintoaMATLABArray

[xin,fs,nbits]=wavread(filename); [xin,fs]=loadwav(filename);

filenameisascii textfora.wavencodedfilewhichcontainsaspeechsignalencodedusinga16bitintegerformat

xin istheMATLABarrayinwhichthespeechsamplesarestored(indoubleprecisionformat)

fs isthesamplingrateoftheinputspeechsignal nbits isthenumberofbitsinwhicheachspeechsampleisencoded

(16inmostcases) programwavread scalesthespeecharray,xin,torange1xin1,

whereasloadwav preservessamplevaluesofthespeechfileandhencearrayxin isscaledtorange32768xin32767

[xin1,fs,nbits]=wavread(s5.wav); [xin2,fs]=loadwav(s5.wav);

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ReadaSpeechFileintoaMATLABArray %test_wavread.m %testwaveread function % %readspeechsamplesfromfile'test_16k.wav'intoarrayx1usingwavread %routine filein='test_16k.wav'; [x1,fs1,nbits]=wavread(filein); %printoutvaluesoffs1,nbits,wavmin1,wavmax1 wavmin1=min(x1); wavmax1=max(x1); fprintf('file:%s,wavmin/wavmax:%6.2f%6.2f,fs1:%d,nbits:%d\n, filein,wavmin1,wavmax1,fs1,nbits); %readspeechsamplesfromsamefileintoarrayx2usingloadwav routine [x2,fs2]=loadwav(filein); %printoutvaluesoffs2,nbits,wavmin2,wavmax2 wavmin2=min(x2); wavmax2=max(x2); fprintf('file:%s,wavmin/wavmax:%d%d,fs2:%d\n',... filein,wavmin2,wavmax2,fs2);TerminalDisplay:file:test_16k.wav,wavmin/wavmax:1.001.00,fs1:16000,nbits:16file:test_16k.wav,wavmin/wavmax:3276832767,fs2:16000 4

HelloWorld GUI25

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GUI25InitialScreen

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GUI25EditScreen

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Play/PlotExistingSpeechFile Play_Plot_Speech_GUI25.m

MATLABGUIforbasicoperationsofreadinginafile,playingthespeecharray,andplottingthespeechwaveform

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WriteaSpeechArrayintoaSpeechFile

wavwrite(xout,fs,nbits,filename); savewav(xout,filename,fs);

xout istheMATLABarrayinwhichthespeechsamplesarestored fs isthesamplingrateoftheoutputspeechsignal nbits isthenumberofbitsinwhicheachspeechsampleisencoded filenameistheascii textforthe.wavencodedfileinwhichthe

MATLABsignalarrayistobestored forwavwrite theMATLABarrayxout needstobescaledtotherange

1xin1whereasforsavewav theMATLABarrayxout needstobescaledtotherange32768xout32767

wavwrite(xin1,fs,s5out.1.wav); savewav(xin2,s5out.2.wav,fs);

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WriteaSpeechArrayintoaSpeechFile

%writeoutarrayx1intospeechfileusingwavwrite routine wavwrite(x1,fs1,nbits,'file1out.wav');

%writeoutarrayx2intospeechfileusingsavewav routine savewav(x2,'file2out.wav',fs2);

file1out.wav

file2out.wav

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PlayaSpeechFile sound(x,fs); soundsc(x,fs);

forsoundthespeecharray,x,mustbescaledtotherange1x1

forsoundsc anyscalingofthespeecharraycanbeused fs isthesamplingratefthespeechsignal

[xin,fs]=loadwav(s5.wav);%loadspeechfroms5.wav; xinn =xin/abs(max(xin));%normalizetorangeof1to1; sound(xinn,fs);%playoutnormalizedspeechfile; soundsc(xin,fs);%playoutunnormalized speechfile;

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PlayMultipleSpeechFiles play_multiple_files.m;

sequenceoffilenamesreadinviafilelist,keyboardorfilesearch

Exampleofusagetoplayout3speechfilesinsequence: kbe=filenameentryviafilelist(2),keyboard(1),orfilesearch(0):1;%keyboardchosen

N=numberoffilestobeplayedinagroup:3;%playout3files

i=1;filename:s1.wav; i=2;filename:s2.wav; i=3;filename:s3.wav

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PlayMultipleSpeechFiles

test_play_files.m playthefollowingsequenceoffiles:

Maple_short.wavs1.wavbeep.wavtest_16k.wavbeep.wavs2.wav

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RecordSpeechintoMATLABArray

record_speech.m (callsMATLABfunctionwavrecord.m)

functiony=record_speech(fs,nsec); fs:samplingfrequency nsec:numberofsecondsofrecording y:speechsamplesarraynormalizedtopeakof32767

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RecordSpeechintoMATLABArray record_display_speech_GUI25.m

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PlotSpeechUsingStripsPlot

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PlotSpeechUsingStripsPlot strips_plot_GUI25.m

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PlotSpeechUsing4LinePlot

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SampleRateConversion

y=srconv(x,fsin,fsout); x:inputspeecharray; fsin:inputspeechsamplingrate; fsout:desiredspeechsamplingrate;

Example: [xin,fsin]=loadwav(s5.wav);%fsin=8000; fsout =10000;%desiredsamplingrate; y=srconv(xin,fsin,fsout);

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SampleRateConversion SRC_GUI25.m

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FilterSpeechWaveform

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FilterSpeechWaveform filter_GUI25.m

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PlotSignalandSTFTLogMagnitude

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MultipleSpectraGUI multiple_spectra_GUI25.m

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PlotSpectrogram

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PlotSpectrogram spectrogram_GUI25.m

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PlotMultipleSpectrograms

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