Integral Of Audio Signal

Hello everyone, I take my sound from microphone and my main purpose is calculating the Fourier Coefficients of it and coverge it.

But I need to calculate the integral of my audio signal because I need to calculate the coefficients. I tried xtrapz(x,y) and int functions but they don't meet my requirements. How can I calculate the integral of my sound? Thanks.

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Error using trapz (line 15)

LENGTH(X) must equal the length of Y in dim 1.

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Undefined function 'int' for input arguments of type 'double'.

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Also I need some suggestions about the calculating coefficients, thanks.

My code:

recorder= audiorecorder(16000,8,2);

disp('please record your voice');

drawnow();

pause(1);

recordblocking(recorder, 5);

play(recorder);

data=getaudiodata(recorder);

x=0.2:pi/1000:2.2;

trapz(x,data)

Answer 1

[Walter Roberson]

Fs =  16000;
trapz(data)/Fs

But if you need the fourier coefficients then just fft(data)

[enrique128]

sir when i apply trapz it gives me two values, what does it mean and which is true value they are nearly the same also what is the meaning of 16000 sir? thanks.

[Walter Roberson]

On my phone, semi-colon is long-press n and I did not hold the n long enough.

fft(data) should be returning a complex array that is approximately 80000 x 2 (sampling frequency times duration). Some of the entries might be 0.

[Walter Roberson]

audiorecoder(16000,8,2) means to record with a sampling frequency of 16000 Hz, 8 bits per channel, 2 channels. You are getting two results because you are getting a result for each channel.

If you are calculating the coefficients for discrete fourier transform (fft) then you should not be integrating the signal, and you should be summing the signal instead, sum(data)

[enrique128]

sir im not calculating dft i will converge it with fourier series so i will not use fft. Is it possible?