filename = "test.wav";
[y,fs] = audioread(filename);
L = size(y,1);
t = linspace(0, L-1, L)/fs; % Time Vector
fs_new = 8000;
[yr,tr] = resample(y, t(:), fs_new); % Resample To New Sampling Frequency
There are several compatible resample syntaxes that will do what you want. I prefer the one I posted here.
Alternatively, the interp1 funciton can be uesd, however resample includes an anti-aliasing filter, so it is best for any sort of signal processing.
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