A low-complexity voice activity detector for smart hearing protection of hyperacusic persons
Narimene Lezzoum, Ghyslain Gagnon, Jérémie Voix · 2013
In this paper, a Voice Activity Detector (VAD) is proposed for smart hearing protection applications where speech is to get through the hearing protector while ambient noise is to be blocked out.The VAD calculates a short-term statistical assessment of the temporal envelopes within different frequency bands.This assessment uses the Inter-Quartile Range (IQR) and reflects the dispersion of the envelopes' magnitudes.The VAD's decision is made using two threshold comparison rules and a hangover scheme triggered after a given number of observations.These four parameters have been optimized off-line using a genetic algorithm approach.The performance of the proposed VAD is compared to Sohn's VAD using a database of 90 speech signals corrupted by five real-world noise environments at Signal-to-Noise ratios (SNR) varying from 0 to +10 dB.Results show that the proposed VAD performs better than Sohn's VAD with an 85.9% (compared to 77.5%) F1 score averaged across all SNRs and also minimizes by a factor of three the mid-speech clipping rate.In addition, the evaluation of the proposed VAD's computational cost shows that its implementation on-board a low-power low-consumption DSP is very feasible and would enable smart hearing protection for hypersensitive persons.