Robust Voice Activity Detection using Group Delay Functions
Sree Hari Krishnan P, R. Padmanabhan, Hema A. Murthy · 2006
In this paper, we present an algorithm for Voice Activity Detection (VAD) in speech signals with very low SNR. In the proposed algorithm, the short-term energy of the speech signal is viewed as the positive frequency part of the magnitude spectrum of a minimum phase signal. The group delay of this signal is then computed. The speech regions of the signal are characterized by well-defined peaks in the group delay spectrum, while the non-speech regions are identified by well-defined valleys. The proposed method is compared experimentally with G.729 Annex B in very low SNR conditions with different types of noises and is found to perform significantly better.