There is a speech signal, $y[n]$, in the time-domain.
To take it to the frequency-domain, DCT has been got from $y[n]$ (
w = dct(y) in MATLAB).
After it, I applied LPC on this signal ($w[k]$) in the frequency-domain to find the coefficients. Tthe following process was used:
yfft = fft(w); yidft = ifft(yfft.*conj(yfft)); a = levinson(yidft,p);
My question is: what domain does the signal resulting from applying FFT to a DCT (i.e. $w$) belong to? Also, taking the FFT from a signal leads to the frequency-domain, right?