performing a deconvolution on signals

Question

Joseph Tabbah 2022-11-23

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1860958-performing-a-deconvolution-on-signals

回答： Sai Kiran 2022-12-23

i took 2 signals and convolved them to encrypt the signal, how can i separate the 2 audios using a known audio?

% this project is a door locking and unlocking mechanism using an audio
% file , by taking an input form a user we store the file in the memory
% then we encrypt it with another audio file using convolution, the user
% enters the audio file 2 , in this case the chicken sound into the door
% and using deconcolution we decrypt the signal once again
% first we record an audio to store in matlab
recObj = audiorecorder
recDuration = 5;
disp("Begin speaking.")
recordblocking(recObj,recDuration);
disp("End of recording.")
play(recObj);
y = getaudiodata(recObj);
plot(y);
% we read the audio file 2 that we have stored on our device
[audio2,fs] = audioread('chicken-2.wav');
% we take the audio from file transform it to the frequency domain
W=length(audio2);
b=(1/W)*ones(1,W);
F= fft(audio2);
H1= fftshift(F);
S1 = log(1+abs(H1));
figure(1);plot(S1);
title('Fourrier transform of audio 1')
% we filter and fourier transform the audio we recorded
W2=length(y);
b2=(1/W2)*ones(1,W2);
a2=1;
audiohe1=filter(b2,a2,audio2);
F2= fft(audio2);
H2= fftshift(F2);
S2 = log(1+abs(H2));
figure(2);
plot(S2);
title('Fourrier transform of audio 2')
%bow we have to make them the same lengh
% this is useful to encrypt the signal and to compare the signals later
%make both signals same size
if W>W2
    S1=resample(S1,W,W2);
end
if W<W2
    S2=resample(S2,W,W2);
end
figure
aud_pad =  cat(1,y(:,1),zeros(7890000,1));  %we pad the audios with zeros
aud_pad2 =  cat(1,audio2(:,1),zeros(458383,1));  
aconv=conv(y(:,1),audio2(:,1));
sound(aconv)
plot(aconv);
title('Convolutions');
s5 = ifft(aconv);
plot(s5);
title('signal in time domain')
%now the sound is ecrypted all what we have left to do is deconvolve