This paper deals with an HMM-based automatic phonetic segmentation (APS) system and proposes to increase its performance by employing a pitch-synchronous (PS) coding scheme. Such a coding scheme uses different frames of speech throughout voiced and unvoiced speech regions and enables thus better modelling of each individual phone. The PS coding scheme is shown to outperform the traditionally utilised pitch-asynchronous (PA) coding scheme for two corpora of Czech speech (one female and one male) both in the case of a base (not-refined) APS and in the case of a CART-refined APS. Better results were observed for each of the voicing-dependent boundary types (unvoiced-unvoiced, unvoiced-voiced, voiced-unvoiced and voiced-voiced).
Bibliographic reference. Matoušek, Jindřich / Romportl, Jan (2008): "Automatic pitch-synchronous phonetic segmentation", In INTERSPEECH-2008, 1626-1629.