butterbfilt.m

使用Matlab实现了FIR与IIR滤波器

function [ output_args ] = Untitled4( input_args )
%UNTITLED4 Summary of this function goes here
%  Detailed explanation goes here
[y,ft,bits]=wavread('hello.wav');
subplot(2,1,1);
plot(y);
xlabel('Time Index t');
ylabel('Amplitude');
title('原始时域图象');
Wp1 =2*1200/ft;
Wp2 =2*3000/ft;
Ws1 =2*1000/ft;
Ws2 =2*3200/ft;
Wp=[Wp1,Wp2];
Ws=[Ws1,Ws2];
Rp = 1;
Rs = 100;
[N,Wn] = buttord(Wp,Ws,Rp,Rs);
[b,a] = butter(N,Wn);
v=filter(b,a,y);
subplot(2,1,2);
plot(v);
xlabel('Time Index t');
ylabel('Amplitude');
title('BUTTER带通滤波时域图象');
sound(v,ft,bits);