exmp2_4.m

用dsp解压mp3程序的算法

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% exmp2_4.m - Moving-average filter
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L = 4;              % moving-average filter of order 4
load -ascii xn.dat; % load noisy sinewave into xn
N = length(xn);     % length of xn vector
n = [0:N-1];        % time index
b = ones(L,1)/L;    % initialize coefficient vector
yn = filter(b,1,xn);% FIR filtering
plot(n,xn,'--b',n,yn,'-r') % plot both input & output
title('Input & output of moving-average filter');
xlabel('Time index, n'); ylabel('Amplitude');
axis([0 N-1 -inf inf])