英语声学和语音学英文版讲义

1、July 1st, 2002Speech acoustics and phonetics, Il Ciocco1OverviewnDynamics in speech acousticsnContour modeling (mainly formants)nAspects of spectral undershootnModeling V and C reductionnPhonetic knowledge from speech corporanIFA, CGN, TIMIT, found speechnConclusionsJuly 1st, 2002Speech acoustics an

2、d phonetics, Il Ciocco3Dynamics in speech acousticsnDynamics is the norm, not stationaritynarticulatory efficiencynDynamics is everywherengenerally no word boundaries in speechndeletion of words, syllables, phonemes; insertionnwithin/between word coarticulation/assimilationnvowel and consonant reduc

3、tionnAcoustic manifestationsnsegment duration, F0, loudness, spectral qualityJuly 1st, 2002Speech acoustics and phonetics, Il Ciocco4Dynamics is the normnThe speaker speaks as sloppily as the listeners allow him to do in communicationncommunicative efficiencynArticulatory vs. perceptual efficiencynd

4、o spectral transitions facilitate or hamper perception? see other presentationnSpeaker flexibility; speaking style (clear vs. sloppy); speaking rateJuly 1st, 2002Speech acoustics and phonetics, Il Ciocco5Dynamics is everywherenDeletionnbread and butter /brEmbY3/nAmsterdam (Du) /AmstrdAm/ /AmsdAm/nko

5、ninklijke (Du) /konIklk/ /kolk/nInsertionnhomorganic glide insertion: die een (Du) /dijn/nDegeminationnis zichtbaar (Du) /Is zIxtbar/ /IsIxbar/nReduction, coarticulation, assimilationJuly 1st, 2002Speech acoustics and phonetics, Il Ciocco6Acoustic manifestationsnpitch, loudness, formant, component c

6、ontoursncontour stylization (e.g., pitch in praat)ncontour modelingnn-th degree curve fitting(D.van Bergem)nLegendre polynomials)(R.van Son)n16 points per segment)n(phoneme) segmentationnby hand (time consuming; non-consistent)nautomatically (via forced phoneme recognition and a pronunciation lexico

7、n with alternatives; systematic errors)July 1st, 2002Speech acoustics and phonetics, Il Ciocco7Contour modelingnallows modeling of specific phenomenanpitch accentuation (vs. vowel onset)nreduction, centralization, undershootnallows generation of stimuli for perc. expts.nphoneme identification in ext

8、ending contextn2-alternatives forced choice identif. of continuandiscrimination, RTnallows statistics on large speech corporanTIMIT, CGN, IFA-corpus, SwitchboardJuly 1st, 2002Speech acoustics and phonetics, Il Ciocco8Static vs. dynamic V recogn.nsee Weenink (2001)n“Vowel normalizations with the TIMI

9、T acoustic phonetic speech corpus”, IFA Proc. 24, 117-123n438 males, both train & test sent. of TIMITn35,385 vowel segments, hand segmentedn13 monophthongeal vowel categoriesn1-Bark bandfilter anal. (18), intensity. normal.n3 frames per segment: central and 25 ms L/RJuly 1st, 2002Speech acoustic

10、s and phonetics, Il Ciocco9Some resultsnVowel classif. (%) with discriminant functionsCondition# ItemsStatic 1 frameDynamic 3 framesOriginal35,385438x13x(125)59.366.9speaker normalized35,38562.269.2V centers per speaker5,374438x1378.990.1speaker normalized5,37487.994.5July 1st, 2002Speech acoustics

11、and phonetics, Il Ciocco10Formant tracks / speaking ratenPh.D. thesis Rob van Son (1993)n“Spectro-temporal features of vowel segments”nsee also Speech Comm. 13, 135-148 (Pols & vSon)n850-words text, read at normal and fast ratenhand segmentation of 7 most freq. V + schwanformant tracksnvia 16 po

12、ints per segm. or 5 Legendre polynomialsninfluence of rate, V-dur., context, sent. acc.nevidence for duration-controlled undershoot?July 1st, 2002Speech acoustics and phonetics, Il Ciocco11Some resultsnno differences for F1/F2 in vowel center for normal- or fast-rate speech; only some over- all rise

13、 in F1 for fast rate (irrespective of V)nsame formant track shape (normalized to 16 points) for normal- or fast-rate speechnsame results when using the more elaborate Legendre polynomialsnConcl.: changes in V-duration do not change the amount of undershoot active control of articulation speedJuly 1s

14、t, 2002Speech acoustics and phonetics, Il Ciocco12Formant representations800100012001400160018002000300400500600yoauiNormal rate Fast rateF -1F -2-250-200-150-100-50050100150200250-150-100-50050ayouiNormal rate Fast rateF -2F -1zeroth order Legendre Legendre polynomial coefficients (mean Fi in vowel

15、 segment)second order polynomials (axes reversed)eeJuly 1st, 2002Speech acoustics and phonetics, Il Ciocco13Modeling vowel reductionnPh.D. thesis Dick van Bergem (1995)n“Acoustic and lexical vowel reduction”nsee also Speech Communication 16, 329-358nlexical V reduction Fr /bet/ vs. Du /btOn/nacousti

16、c V reduction /banan, bAnan, bnan/ nf(sent. acc., w. str., w. class): can-candy-canteenncoarticulatory effects on the schwanC1C2V- and VC1C2-type nonsense wordsnperceptual effects (full V or schwa, f.i. ananas)July 1st, 2002Speech acoustics and phonetics, Il Ciocco14Some resultsThe schwa is not just

17、 a centralized vowel but somethingthat is completely assimilated with its phonemic contextt-nw-lJuly 1st, 2002Speech acoustics and phonetics, Il Ciocco15Modeling consonant reductionnSp. Comm. (1999) 28, 125-140 (vSon & Pols)n20 min. speech, both spontaneous and readn2 x 791 similar VCV; hand seg

18、mentedn5 aspects of V and C reductionnrelated to coarticulation: F2 slope differences at CV- vs. VC-boundaries; F2 locus equations (F2 onset vs. F2 target)nrelated to speaking effort: duration; spectral COG (mean freq.); V-C sound energy differencesJuly 1st, 2002Speech acoustics and phonetics, Il Ci

19、occo16Some resultsnV markedly reduced in spontaneous speechnlower F2-slope diff. in spontaneous speech decrease in articulation speednno systematic effect on F2 locus equation; V onsets and targets change in concert any V reduction mirrored by comparable change in Cnspont. sp.: V and C shorter; lowe

20、r COG decrease in vocal and articulatory effortJuly 1st, 2002Speech acoustics and phonetics, Il Ciocco17Access to large corporanmore, and more realistic, datanphonetic knowledge via statistical analysesnf.i. highly accessible IFA-corpus (free, SQL)nsee “Structure and access of the open source IFA-co

21、rpus”, IFA Proc. 24, 15-26 (vSon & Pols)n4 M/4F speakers, 5.5 hrs of speechnfrom informal to read + sent., words, syllablesn 50Kwords segm. and labeled at phoneme levelJuly 1st, 2002Speech acoustics and phonetics, Il Ciocco18Some resultsnspeech + annot. + meta data: relational DBnrealization of

22、final n, f.i. Du geven /xev(n)/Style#wrds/n/All% /n/Informal5,2501304305 0.3Retelling6,22913236249 5.2 LFHFNarr. story14,453180372552334230Sentences14,97020334054337Pseudo-sent2,55462198177All43,4564591,2711,73036ReadJuly 1st, 2002Speech acoustics and phonetics, Il Ciocco19Spoken Dutch Corpus (CGN)n

23、10 M words, 1,000 hrs of speechnvariety of styles, incl. telephone speechnadult Dutch and Flemish speakersnfor linguistic and technological researchnsee various LREC and ICSLP papers (2002)nfully transcribed: orthogr., POS, lemmasnpartly transcr.: phonemic, prosodic, syntacticJuly 1st, 2002Speech ac

24、oustics and phonetics, Il Ciocco20TIMITnpopular DB in acoustic phonetics and ASRnalso telephone version (NTIMIT)nhand segmented & labeled at phoneme leveln438 males, 192 females (8 dialect regions)n10 sent./sp. (2 fixed, 1 phon. compact, 7 diverse)sa1: “She had her dark suit in greasy wash water

25、 all year”nincludes separate test data (112 M, 56 F) ne.g. Ph.D thesis X. Wang (1997)“Incorporating knowledge on segmental duration in HMM-based continuous speech recognition”July 1st, 2002Speech acoustics and phonetics, Il Ciocco21RSRoot /iy/LwLucountmeans.d.factorlevel46269539154483311588953614941

26、094679678257118936379125816872973510440379834719983372911954461044291805299111775798052947013618010143310114832210719952945012612186812113498461113749637156229001201201201201230123012001202012263022252750254224360274652232524375827Useful info: durational variabilityAdopted from Wang (1998)normal rat

27、e=95 primary stress=104word final=136utterance final=186overall average=95 ms(fast rate slow rate)histogram count (number of utterances)020406080100120140-0.76-0.53-0.3-0.070.160.390.620.851.081.311.54020406080100120140160180utterance-averaged phone duration (ms)histogramphone durd,normalized phone

28、durationspeaking raterNiiN11,all 3,696 training sent. (sx + si) of TIMIT training set0July 1st, 2002Speech acoustics and phonetics, Il Ciocco23found speechnDARPA-LVSR community rather ambitiousnBroadcast News (BN), Sp.Comm. 37 (2002) 95WSJ NAB read sp.1995Market place1996F0-F5, FX partitioned19973 hrs test unpartit.1998+ non Engl. speech also 900 Mbest % WERon test set27.0 %27.1 %1:4