In previous study we proposed algorithms to select representative frames from a segment for phoneme likelihood evaluation. In this paper we show that this frame selection behavior is phoneme dependent. We observe that some phonemes benefit from frame selection while others do not, and that this separation matches the phonetic categories. For those phonemes sensitive to frame selection, we find that selecting frames at some pre-defined positions in the segment enhances the discrimination between phonemes. These phoneme-dependent positions are explicitly retrieved and used in a phoneme classification task. Experimental results on the TIMIT phonetic database show that the frame selection method significantly outperforms decoding by the classical Viterbi decoder.
Bibliographic reference. Wu, Tingyao / Duchateau, Jacques / Compernolle, Dirk Van (2007): "Phoneme dependent frame selection preference", In INTERSPEECH-2007, 50-53.