Speech and EGG polarity detection using Hilbert Envelope

This work proposes two different methods for polarity detection in speech and Electroglottograph (EGG) signals using Hilbert Envelope (HE). HE is defined as the magnitude of complex time function and hence an unipolar signal. The zero frequency filtering (ZFF) obtained from HE of LP residual is of same phase for both polarity. Alternatively, the ZFF of speech and EGG, integrated linear prediction residual (ILPR) of speech and Difference EGG (DEGG) are out of phase for opposite polarities. These observations are exploited to develop two methods for polarity detection. The methods are evaluated using CMU-Arctic and PTDB-TUG databases and compared with other state-of-the-art methods under clean and noisy conditions. It is found that the performance of the proposed methods are comparable in clean condition and robust under noisy condition to other existing methods.