语音信号处理实验matlab程序

function[rea4]=lpc46(x,first,winlgh,sampling_rate); sw=x(first:(first+winlgh-1))'.*hamming(winlgh); Rsw=xcorr(sw'); t=(first:(first+winlgh-1))*1000/sampling_rate; subplot(1,2,1);plot(t,sw);xlabel('ms');title('加窗后时域波形'); subplot(1,2,2);t=(1:length(Rsw))*1000/sampling_rate;plot(t,Rsw);xlabel('ms');title('加窗后自关波形'); mid=round(length(Rsw)/2); Rsw4=[Rsw(mid:(mid+3));Rsw((mid-1):(mid+2));Rsw((mid-2):(mid+1));Rsw((mid-3):(mid))]; Rsw6=[Rsw(mid:(mid+5));Rsw((mid-1):(mid+4));Rsw((mid-2):(mid+3));Rsw((mid-3):(mid+2));Rsw((mid-4):(mid+1));Rsw((mid-5):(mid))]; rea4=inv(Rsw4)*Rsw((mid+1):(mid+4))'; rea6=inv(Rsw6)*Rsw((mid+1):(mid+6))'; A4=sqrt(Rsw(1)-Rsw((mid+1):(mid+4))*rea4); A6=sqrt(Rsw(250)-Rsw((mid+1):(mid+6))*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); w=(1/1024:1/1024:0.5)*sampling_rate; figure; subplot(2,2,1);plot(w,log(abs(FW3)));xlabel('频率hz');title('加窗后信号频率'); subplot(2,2,2);plot(w,log(abs(HW4)),'g');xlabel('频率hz');title('4极点模型频率响应'); subplot(2,2,3);plot(w,log(abs(HW6)),'r');xlabel('频率hz');title('6极点模型频率响应'); subplot(2,2,4);plot(w,log(abs(FW3)),w,log(abs(HW4)),w,log(abs(HW6)));xlabel('频率hz');title('三者比较');