All-pole group delay features (alternative to MFCCs for feature extraction from speech signals)
featureVectors = extract_lpGdelayVec_diff(speechFrames, LP_ORDER, NFFT);
The featureVectors matrix has one row per frame of speech. featureVectors is a MxNFFT matrix.
speechFrames is a MxN matrix with M frames, each of N samples.
To obtain "usual" features, take a DCT of size P on the featureVectors matrix. P can be, for instance 18, resulting in an 18-dimensional feature vector per frame.
LP_ORDER is the order of the all-pole model, we have usually used 20 for NIST speaker id data.
NFFT is FFT order.