firlfilt.m

使用Matlab实现了FIR与IIR滤波器

function [ output_args ] = Untitled1( input_args )
%UNTITLED1 Summary of this function goes here
%  Detailed explanation goes here
[y,ft,bits]=wavread('hello.wav');
subplot(2,2,1);
plot(y);
xlabel('Time Index t');
ylabel('Amplitude');
title('原始时域图象');grid;
subplot(2,2,2);
plot(abs(fft(y)));
xlabel('Frequence Index w');
ylabel('Amplitude');
title('原始频域图象');grid;
fcutsl=[1000 1200];
magsl = [1 0];
devsl = [(1-10^(-1/20)),10^(-100/20)];
[Nl,Wnl,betal,ftypel] = kaiserord(fcutsl,magsl,devsl,ft);
kaiser(Nl+1,betal);
bl = fir1(Nl,Wnl, kaiser(Nl+1,betal));
vl=fftfilt(bl,y);
subplot(2,2,3);
plot(vl);
xlabel('Time Index t');
ylabel('Amplitude');
title('FIR低通滤波时域图象');grid;
subplot(2,2,4);
plot(abs(fft(vl)));
xlabel('Frequence Index w');
ylabel('Amplitude');
title('低通滤波后频域图象');grid;
sound(vl,ft,bits);