LPC Analysis in Matlab

Matlab for generating original, lpc, and residual spectra.

%lpc
order = fs/1000 + 5; % order
xlpc = lpc(xw, order)'; % coefficients

%windowed speech frequency response
zpf = 3; Nfft = 2^nextpow2(N*zpf);
XW = fft(xw, Nfft);

% lpc spectrum
[H,w] = freqz(1, xlpc, Nfft, 'whole'); 

%inverse filter to obtain residual
E = XW./H;
e = real(ifft(E));

Figure 3: LPC Analysis Results for vowel 'a'.