sine3.m

用dsp解压mp3程序的算法

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% sine3.m - This program generates 3 sinewaves and mixes them
%
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clear all; close all;
F1 = 1000; F2 = 1200; F3 = 1400; % sinewave frequencies
Fs = 10000;                      % sampling frequency
T = 0:1:499;                     % time index
x1 = sin(2*pi*T*F1/Fs) + 0.5*sin(2*pi*T*F2/Fs) + 0.25*sin(2*pi*T*F3/Fs);
figure(1);plot(x1); title('Sine waves');
save in.dat x1 -ascii ;          % save in ASCII file in.dat

x1_int = round(32768*x1./max(abs(x1))); % convert to integer format
i = find(x1_int == 32768);       % find 32768
x1_int(i) = 32767;               % set is to 32767
fid = fopen('in_int.dat','w');   % save signal to file in_int.dat
fprintf(fid,'%4.0f\n',x1_int);   % in integer (Q15) format
fclose(fid);