英语声学和语音学英文版.ppt

July 1st, 2002 Speech acoustics and phonetics, Il Ciocco Speech acoustics and phonetics Louis C.W. Pols Institute of Phonetic Sciences (IFA) Amsterdam Center for Language and Communication (ACLC) Overview Dynamics in speech acoustics Contour modeling (mainly formants) Aspects of spectral undershoot Modeling V and C reduction Phonetic knowledge from speech corpora IFA, CGN, TIMIT, found speech Conclusions Dynamics in speech acoustics Dynamics is the norm, not stationarity articulatory efficiency Dynamics is everywhere generally no word boundaries in speech deletion of words, syllables, phonemes; insertion within/between word coarticulation/assimilation vowel and consonant reduction Acoustic manifestations segment duration, F0, loudness, spectral quality Dynamics is the norm The speaker speaks as sloppily as the listeners allow him to do in communication communicative efficiency Articulatory vs. perceptual efficiency do spectral transitions facilitate or hamper perception? — see other presentation Speaker flexibility; speaking style (clear vs. sloppy); speaking rate Dynamics is everywhere Deletion ‘bread and butter’ /brEmbY3/ ‘Amsterdam’ (Du) /Amst@rdAm/ —/Ams@dAm/ ‘koninklijke’ (Du) /konI?kl@k@/ —/kol@k@/ Insertion homorganic glide insertion: ‘die een’ (Du) /dij@n/ Degemination ‘is zichtbaar’ (Du) /Is zIxtbar/ —/IsIxbar/ Reduction, coarticulation, assimilation Acoustic manifestations pitch, loudness, formant, component contours contour stylization (e.g., pitch in praat) contour modeling n-th degree curve fitting (D.van Bergem) Legendre polynomials ) (R.van Son) 16 points per segment ) (phoneme) segmentation by hand (time consuming; non-consistent) automatically (via forced phoneme recognition and a pronunciation lexicon with alternatives; systematic errors) Contour modeling allows modeling of specific phenomena pitch accentuation (vs. vowel onset) reduction, centralization, undershoot allows generation of stimuli for perc. expts. phoneme identification in extendin