Subband analysis of linear prediction residual for the estimation of glottal closure instants

Many state-of-the-art techniques for estimating glottal closure instants (GCIs) use linear prediction residual (LPR) in one way or another. In this paper, subband analysis of LPR is proposed to estimate the GCIs. A composite signal is derived as the sum of the envelopes of the subband components of the LPR signal. Appropriately chosen peaks of the composite signal are the GCI candidates. The temporal locations of the candidates are refined using the LPR to obtain the GCIs, which are validated against the GCIs obtained from the electroglot-tograph signal, recorded simultaneously. The robustness is studied using additive white, babble and vehicle noises for different signal to noise ratios. The proposed method is evaluated using six different databases and compared with three state-of-the-art LPR based methods. The results show that the performance of the proposed method is comparable to the best of the LPR based techniques for clean as well as noisy speech.