Can anyone explain me this code of mel spaced filter banks? i have to use this in my speaker recognition project.

function m = melfb(p, n, fs)

% MELFB Determine matrix for a mel-spaced filterbank %

% Inputs: p number of filters in filterbank

% n length of fft

% fs sample rate in Hz %

% Outputs: x a (sparse) matrix containing the filterbank amplitudes

% size(x) = [p, 1+floor(n/2)] %

f0 = 700 / fs;

fn2 = floor(n/2);

lr = log(1 + 0.5/f0) / (p+1);

% convert to fft bin numbers with 0 for DC term

bl = n * (f0 * (exp([0 1 p p+1] * lr) - 1));

b1 = floor(bl(1)) + 1;

b2 = ceil(bl(2));

b3 = floor(bl(3));

b4 = min(fn2, ceil(bl(4))) - 1;

pf = log(1 + (b1:b4)/n/f0) / lr;

fp = floor(pf);

pm = pf - fp;

r = [fp(b2:b4) 1+fp(1:b3)];

c = [b2:b4 1:b3] + 1;

v = 2 * [1-pm(b2:b4) pm(1:b3)];

m = sparse(r, c, v, p, 1+fn2);