MATLAB处理语音信号滤波程序 精品资料.doc

MATLAB处理语音信号滤波程序巴特沃思滤波器滤波%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%参数初始化%%%%%%%%%%%%%%%%clearall;%关闭以往仿真的数据栈A=5;%噪声的振幅u1=0.01;%噪声振幅的衰减系数u2=0.02;u3=0.03;f1=50;%多频噪声频率f2=200;f3=800;[Y,fs,bits]=wavread('0601331007.wav')%读出信号1，采样率和采样位数%sound(Y,fs);%[X,Fs,bits]=wavread('0601331007.wav');%读出信号2，采样率和采样位数n=length(Y);%求采样信号1的长度%m=length(X);%求采样信号2的长度t=0:1/fs:(n-1)/fs;%求采样信号1时域上的采样点数%t1=0:1/Fs:(m-1)/fs;%求采样信号2时域上的采样点数%%%%%%t=(0:n-1)/fs;%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%构造噪声%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%y1=u1*A*sin(2*pi*f1*t)+u1*A*sin(2*pi*f2*t)%两两噪声相加y2=u1*A*sin(2*pi*f3*t)y=y1+y2%%%%%%Z1=u1*A*sin(2*pi*f1*t1)+u1*A*sin(2*pi*f2*t1)%两两噪声相加%%%%%%Z2=u1*A*sin(2*pi*f3*t1)%%%%%%Z=Z1+Z2%figure(1)%画出噪声的时域图，取200个点%%%%%%%%%%plot(t,y);gridon;%plot(t(1:200),y(1:200));gridon;%%xlabel('时间(t)');%ylabel('幅度（y)');%title('噪声的时域图');%%Fy=fft(y,n);%对噪声进行傅立叶变换%Fy1=abs(Fy);%n1=floor(n/2);%对zhang求采样点数的一半%n2=floor(m/2);%对zhanglow求采样点数的一半%f=(0:n1)*fs/n;%时域上的采样点数%f1=(0:n2)*Fs/m;%时域上的采样点数%%figure(2)%画出噪声的频谱图%plot(f,Fy1(1:n1+1));gridon;%xlabel('频率（f）');%ylabel('幅度（Fy1）');%title('噪声的频谱图');%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%加噪声前后的时域图比较%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%Y=Y(:,1);%此处假设声音是双声道的，只取单声道作分析%X=X(:,1);%此处假设声音是双声道的，只取单声道作分析Y1=y+Y';%对采样信号进行转置再加上噪声%pause(10);%暂停10ssound(Y1,fs);%读出加噪声后的采样信号%figure(3)%画出加噪声前后的时域比较图%subplot(2,1,1);plot(t,Y);gridon;%plot(t(1:1000),Y(1:1000));gridon;%xlabel('时间(t)');%ylabel('幅度（Y)');%title('加噪声前的时域图');%%subplot(2,1,2);plot(t,Y1);gridon;%%%%%%%%%%plot(t(1:1000),Y1(1:1000));gridon;%xlabel('时间(t)');%ylabel('幅度（Y1)');%title('加噪声后的时域图');%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%加噪声前后的频域图比较%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%FY=fft(Y1,n);%对加噪声后的采样信号1进行傅立叶变换%FY1=abs(FY);%FY2=fft(Y,n);%对加噪声前的采样信号1进行傅立叶变换%FY3=abs(FY2);%FX=fft(X,m);%对加噪声前的采样信号2进行傅立叶变换%FX4=abs(FX);%%figure(4)%画出加噪声前后的频域比较图%subplot(2,1,1);%plot(f,FY3(1:n1+1));gridon;%xlabel('频率（f）');%ylabel('幅度（FY3）');%title('加噪声前的频谱图');%%subplot