DSP语音信号处理论文

DSP语音信号处理课程设计论文

function f=enframe(x,win,inc) nx=length(x(:));nwin=length(win); if (nwin == 1)len = win; else len = nwin; end

if (nargin < 3) inc = len; end

nf = fix((nx-len+inc)/inc);f=zeros(nf,len); indf= inc*(0:(nf-1)).';inds = (1:len);

f(:) = x(indf(:,ones(1,len))+inds(ones(nf,1),:));if (nwin > 1) w = win(:)';f = f .* w(ones(nf,1),:); end

% hObject handle to pushbutton1 (see GCBO)

% eventdata reserved - to be defined in a future version of MATLAB % handles structure with handles and user data (see GUIDATA) % --- Executes on button press in pushbutton2.

function pushbutton2_Callback(hObject, eventdata, handles) [our]=wavread('3.wav');

specgram_hw3p20(our,128,64,10000); specgram_hw3p20(our,256,512,10000);

function [spec] = specgram_hw3p20(x, winlgh, frmlgh, sampling_rate); % specgram_hw3p20(x, winlgh, frmlgh, sampling_rate) %

% function to compute a spectrogram %

% x = input waveform

% winlgh = window length in samples % frmlgh = frame length in samples % sampling_rate = samples/sec % PARAMETERS

%sampling_rate = 10000; % sampling rate lfft = 1024; % FFT length lfft2 = lfft/2;

%winlgh = 200; % (128) window length (in samples) %frmlgh = 10; % frame interval (in samples) noverlap = winlgh - frmlgh; % x = x(1:4500); x = 2.0*x/max(abs(x));

etime = length(x)/sampling_rate;

%--------------------------------------------------------------------%

spec = abs(specgram(x, lfft, sampling_rate, winlgh, noverlap));

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DSP语音信号处理课程设计论文

subplot(211);

plot((1:length(x))/sampling_rate,x)

xlabel('Time (s)');title('SPEECH');axis([0 etime -2.5 2.5]);grid; subplot(212)imagesc(0:.010:etime,

0:1000:(sampling_rate/2),log10(abs(spec)));axis('xy') xlabel('Time (ms)'),ylabel('Frequency (Hz)'); title('SPECTROGRAM');

% hObject handle to pushbutton2 (see GCBO)

% eventdata reserved - to be defined in a future version of MATLAB % handles structure with handles and user data (see GUIDATA) % --- Executes on button press in pushbutton3.

function pushbutton3_Callback(hObject, eventdata, handles) clc; clear;tic,

[y,fs]=wavread('3.wav');L=length(y); fw=y.*hamming(L);r=real(log(fft(fw,L))) pfw=cceps(fw);rpfw=rceps(fw);z=rpfw(1:30); p=pfw(31:L)logz=real(exp(fft(z,L))); logp=real(fft(p));

% hObject handle to pushbutton3 (see GCBO)

% eventdata reserved - to be defined in a future version of MATLAB % handles structure with handles and user data (see GUIDATA) % --- Executes on button press in pushbutton4.

function pushbutton4_Callback(hObject, eventdata, handles)

speech1_10k=wavread('3.wav',[1024 1273]);sw=speech1_10k.*hamming(250); Rsw=xcorr(sw');t=0.1:0.1:25;subplot(1,2,1);plot(t,sw);xlabel('ms'); Rsw4=[Rsw(250:253);Rsw(249:252);Rsw(248:251);Rsw(247:250)];Rsw6=[Rsw(250:255);Rsw(249:254);Rsw(248:253);Rsw(247:252);Rsw(246:251);Rsw(245:250)]; rea4=inv(Rsw4)*Rsw(251:254)'

rea6=inv(Rsw6)*Rsw(251:256)'; A4=sqrt(Rsw(250)-Rsw(251:254)*rea4); A6=sqrt(Rsw(250)-Rsw(251:256)*rea6); w=pi/512:pi/512:pi; j=sqrt(-1); FW4=rea4'*[exp(-j*w);exp(-j*w*2);exp(-j*w*3);exp(-j*w*4)];FW6=rea6'*[exp(-j*w);exp(-j*w*2);exp(-j*w*3);exp(-j*w*4);exp(-j*w*5);exp(-j*w*6)]; HW4=A4./(1-FW4); HW6=A6./(1-FW6);FW2=fft(sw,1024); FW3=FW2(1:512);

% hObject handle to pushbutton4 (see GCBO)

% eventdata reserved - to be defined in a future version of MATLAB % handles structure with handles and user data (see GUIDATA)

% --- Executes on button press in pushbutton5.

function pushbutton5_Callback(hObject, eventdata, handles) clear

Y=wavread('3.wav',[1 1800]);

x1=Y(271:510);x2=Y(271:510);x3=Y(271:510);

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DSP语音信号处理课程设计论文

%×??à1?·¨ r=zeros(1,240); for k=1:240 for n=1:240-k

r(k)=r(k)+x1(n)*x1(n+k); end end

for k1=1:1:240 if x2(k1)>0 x2(k1)=1; else if x2(k1)==0 x2(k1)=0; else if x2(k1)<0 x2(k1)=-1; end end end end j=1:240; for k1=1:1:240 ma=abs(max(x3)); tc=0.6*ma; if x3(k1)>tc

x3(k1)=x3(k1)-tc; else if x3(k1)<-tc x3(k1)=x3(k1)+tc; else

x3(k1)=0; end end end j=1:240;

% hObject handle to pushbutton5 (see GCBO)

% eventdata reserved - to be defined in a future version of MATLAB % handles structure with handles and user data (see GUIDATA) % --- Executes on button press in pushbutton6.

function pushbutton6_Callback(hObject, eventdata, handles) clear clc

winsize=256; % ′°3¤ winsize=256; % ′°3¤

[speech,fs,nbits]=wavread('3.wav'); size=length(speech); numofwin=floor(size/winsize);

ham=hamming(winsize)';hamwin=zeros(1,size); enhanced=zeros(1,size);

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DSP语音信号处理课程设计论文

x=speech'+ n*randn(1,size);

noisy=n*randn(1,winsize); N = fft(noisy); nmag= abs(N); for q=1:2*numofwin-1

frame=x(1+(q-1)*winsize/2:winsize+(q-1)*winsize/2);hamwin(1+(q-1)*winsize/2:winsize+(q-1)*winsize/2)=hamwin(1+(q-1)*winsize/2:winsize+(q-1)*winsize/2)+ham; y=fft(frame.*ham); mag = abs(y);

phase = angle(y);for i=1:winsize if mag(i)-nmag(i)>0 clean(i)= mag(i)-nmag(i); else;clean(i)=0; end end

fff=exp(j*phase); spectral=clean.*fff;

enhanced(1+(q-1)*winsize/2:winsize+(q-1)*winsize/2)=enhanced(1+(q-1)*winsize/2:winsize+(q-1)*winsize/2)+real(ifft(spectral)); end

for i=1:size if hamwin(i)==0 enhanced(i)=0; else

enhanced(i)=enhanced(i)/hamwin(i); end end

SNR1 = 10*log10(var(speech')/var(noisy));SNR2 =

10*log10(var(speech')/var(enhanced-speech'));wavwrite(x,fs,nbits,'noisy.wav');wavwrite(enhanced,fs,nbits,'enhanced.wav'); subplot(3,1,1);plot(speech');title(['Original Voice (n=',num2str(n),')' ]);

specgram(speech'); title(['Original Voice (n=',num2str(n),')' ]); subplot(3,1,2); plot(x);

title(['Noise Added (SNR=',num2str(SNR1),'dB)']);

specgram(x);title(['Noise Added (SNR=',num2str(SNR1),'dB)']); subplot(3,1,3);plot(enhanced);

title(['Improved Voice (SNR=',num2str(SNR2),'dB SNR=',num2str(SNR2-SNR1),'dB)']); specgram(enhanced);

title(['Improved Voice (SNR=',num2str(SNR2),'dB SNR=',num2str(SNR2-SNR1),'dB)']); pause; sound(speech);pause; sound(x);pause; sound(enhanced);

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DSP语音信号处理课程设计论文

参考文献

【1】 楼顺天，李博菡. 基于MATLAB的系统分析与设计－信号处理[M]. 西安：

西安电子科技大学出版社，1998.

【2】程佩青．数字信号处理教程［M］．北京：清华大学出版社，2002．

【3】刘庆华,陈紫强,基于MATLAB和DSP的语音信号处理课程的建设,电气电子教学学报,Vol.28,No.4,26-28,2006.

【4】 张力,MATLAB在语音信号处理辅助教学中的应用,电气电子教学学报,2005年27卷2 期,96-99.

【5】 胡航,语音信号处理,哈尔滨工业大学出版社,2005年2月.

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