yuying.m

利用MATLAB实现语音去噪

%在噪声环境下语音信号的增强 

%语音信号为读入的声音文件 

%噪声为正态随机噪声 

sound=wavread('voice.wav'); 

count1=length(sound); 

noise=0.05*randn(1,count1); 

for i=1:count1 

signal(i)=sound(i)

end 

for i=1:count1 

y(i)=signal(i)+noise(i)

end 

%在小波基'db3'下进行一维离散小波变换 

[coefs1,coefs2]=dwt(y,'db3'); %[低频 高频] 

count2=length(coefs1); 

count3=length(coefs2); 

energy1=sum((abs(coefs1)).^2); 

energy2=sum((abs(coefs2)).^2); 

energy3=energy1+energy2; 

for i=1:count2 

recoefs1(i)=coefs1(i)/energy3

end 

for i=1:count3 

recoefs2(i)=coefs2(i)/energy3

end 

%低频系数进行语音信号清浊音的判别 

zhen=160; 

count4=fix(count2/zhen); 

for i=1:count4 

n=160*(i-1)+1:160+160*(i-1) 

s=sound(n); 

w=hamming(160); 

sw=s.*w; 

a=aryule(sw,10); 

sw=filter(a,1,sw); 

sw=sw/sum(sw); 

r=xcorr(sw,'biased'); 

corr=max(r); 

%为清音（unvoice）时，输出为1；为浊音（voice）时，输出为0 

if corr>=0.8 

output1(i)=0; 

elseif corr<=0.1 

output1(i)=1; 

end 

end 

for i=1:count4 

n=160*(i-1)+1:160+160*(i-1); 

if output1(i)==1 

switch abs(recoefs1(i)) 

case abs(recoefs1(i))<=0.002 

recoefs1(i)=0; 

case abs(recoefs1(i))>0.002 & abs(recoefs1(i))<=0.003 

recoefs1(i)=sgn(recoefs1(i))*(0.003*abs(recoefs1(i))-0.000003)/0.002; 

otherwise recoefs1(i)=recoefs1(i); 

end 

elseif output1(i)==0 

recoefs1(i)=recoefs1(i); 

end 

end 

%对高频系数进行语音信号清浊音的判别 

count5=fix(count3/zhen); 

for i=1:count5 

n=160*(i-1)+1:160+160*(i-1); 

s=sound(n); 

w=hamming(160); 

sw=s.*w; 

a=aryule(sw,10); 

sw=filter(a,1,sw); 

sw=sw/sum(sw); 

r=xcorr(sw,'biased'); 

corr=max(r); 

%为清音（unvoice）时，输出为1；为浊音（voice）时，输出为0 

if corr>=0.8 

output2(i)=0; 

elseif corr<=0.1 

output2(i)=1; 

end 

end 

for i=1:count5 

n=160*(i-1)+1:160+160*(i-1); 

if output2(i)==1 

switch abs(recoefs2(i)) 

case abs(recoefs2(i))<=0.002 

recoefs2(i)=0; 

case abs(recoefs2(i))>0.002 & abs(recoefs2(i))<=0.003 

recoefs2(i)=sgn(recoefs2(i))*(0.003*abs(recoefs2(i))-0.000003)/0.002; 

otherwise recoefs2(i)=recoefs2(i); 

end 

elseif output2(i)==0 

recoefs2(i)=recoefs2(i); 

end 

end 

%在小波基'db3'下进行一维离散小波反变换 

output3=idwt(recoefs1, recoefs2,'db3'); 

%对输出信号抽样点值进行归一化处理 

maxdata=max(output3); 

output4=output3/maxdata; 

%读出带噪语音信号，存为'101.wav' 

wavwrite(y,5500,16,'C:\101.wav'); 

%读出处理后语音信号，存为'102.wav' 

wavwrite(output4,5500,16,'C:\102.wav');