730 likes | 1.34k Views
Phonetics. Janice Fon Graduate Institute of Linguistics National Taiwan University. Overview. Speech sounds and phonetic transcription Articulatory phonetics Phonological categories and pronunciation variation Acoustic phonetics and signals Phonetic resources
E N D
Phonetics Janice Fon Graduate Institute of Linguistics National Taiwan University
Overview • Speech sounds and phonetic transcription • Articulatory phonetics • Phonological categories and pronunciation variation • Acoustic phonetics and signals • Phonetic resources • Advanced: articulatory and gestural phonology
Speech sounds and phonetic transcription (1) • Phonetics • The study of speech sounds used in the languages of the world • Phone • A speech sound • Represented with phonetic symbols • Two types: • Consonants • Vowels
Speech sounds and phonetic transcription (2) • Phonetic alphabets • IPA • Standard developed by International Phonetic Association • Alphabet + principles of transcription • ARPAbet • Designed for American English in ASCII symbols • Computer-friendly
Articulatory phonetics (1) • Definition: • The study of how phones are produced • The vocal organ
Articulatory phonetics (2) • Sounds are formed by the motion of air through the mouth • Consonants: • Made by restricting or blocking the airflow in some way • May be voiced or voiceless • Vowels: • Made with less obstruction • Usually voiced • Generally louder and longer than consonants
Articulatory phonetics (3) • Consonants are defined by • Place of articulation • The point of maximum constriction • Manner of articulation • How the restriction of airflow is made • Voicing • State of the glottis
Articulatory phonetics (4) • Place of articulation coronal
Articulatory phonetics (5) • Labial • Sounds whose main restriction is formed at the lips • Two subtypes: • Bilabial: two lips • Labiodental: upper teeth + lower lip • Examples • [國]: [p] 爸, [pʰ] 怕, [m] 媽, [f] 法 • [閩]: [b] 肉, [p] 爸, [pʰ] 打, [m] 媽 • [E]: [p] spy, [pʰ] pie, [m] my, [f] four, [v] very
Articulatory phonetics (6) • Dental • Sounds made by placing the tongue against the teeth • Two subtypes: • Dental: behind the teeth • Interdental: between the teeth • Examples • [國]: [t̪] 大, [t̪ʰ] 踏, [s̪] 撒, [t̪s̪] 資, [t̪s̪ʰ]刺, [n̪] 那, [l̪] 辣 • [閩]: [t̪] 大, [t̪ʰ] 拖, [s̪] 沙, [z̪] 熱, [t̪s̪] 十, [t̪s̪ʰ]柴, [n̪] 藍, [l̪] 賴, [ɾ̪]賊仔 • [E]: [θ] thing, [ð] the
Articulatory phonetics (7) • Alveolar • Sounds made by placing the tongue against the alveolar ridge • Two subtypes: • Alveolar: b/t teeth and alveolar ridge • Postalveolar/palato-alveolar: after the alveolar ridge • Examples • [E]: [t] ten, [d] duck, [n] new, [s] sing, [z] zoo, [l] love, [ɹ] red, [ɾ] butter, [ʃ] she,[ʒ] garage, [tʃ] China, [dʒ] joy
Articulatory phonetics (9) • Palatal • Sounds made by placing the tongue against the (hard) palate • Two subtypes: • Prepalatal/alveolopalatal: the arc towards the roof of the mouth • Palatal: the roof of the mouth • Examples • [國]: [ɕ] 削, [tɕ] 交, [tɕʰ] 敲, [j] 妖 • [閩]: [ɕ] 是, [tɕ] 摺, [tɕʰ] 試, [ʑ] 皺, [j] 妖 • [E]: [j] yes
Articulatory phonetics (10) • Velar • Sounds made by placing the tongue against the velum/soft palate • Examples • [國]: [k] 該, [kʰ] 開, [x] 害, [ŋ] 忙 • [閩]: [k] 該, [kʰ] 開, [g] 牛, [ŋ] 黃 • [E]: [k] ski, [kʰ] key, [g] good, [ŋ] sing
Articulatory phonetics (11) • Glottal • Sounds made at the glottis • Examples • [國]: [ʔ] 唉 • [閩]: [h] 海, [ʔ] 食 • [E]: [h] high, [ʔ] uh-oh
Articulatory phonetics (12) • Retroflex • Sounds made with the tongue tip curled back • Examples • [國]: [ʂ] 扇, [tʂ] 詹, [tʂʰ] 蟬, [ʐ]然
Articulatory phonetics (13) • Manner of articulation • Stop • Nasal • Fricative • Affricates • Approximant • Flap/tap
Articulatory phonetics (14) • Stop • = plosive • Two phases: • Closure: airflow is completely blocked for a short time • Release: an explosive sound as the air is released • Three types: • Aspirated: closure + release + big puff of air • Unaspirated: closure + release + small puff of air • Unreleased stops: closure • Examples • [國]: [p] 爸, [pʰ] 怕, [t̪] 打, [t̪ʰ] 踏, [k] 乾, [kʰ]看 • [閩]: [p] 爸, [pʰ] 打, [b] 肉, [t̪] 踏, [t̪ʰ] 桃, [k] 菇, [kʰ] 苦, [g] 牛, [p ̚] 十, [t ̚] 結, [k ̚] 角 • [E]: [p] spy, [pʰ] pie, [b] buy, [t] story, [tʰ] tie, [d] die, [k] sky,[kʰ] key, [g] guy
Articulatory phonetics (15) narrow glottal opening wide glottal opening voiceless spy pie 鼻 皮 voiced buy to buy 抹
Articulatory phonetics (16) • Nasal • Made by lowering the velum and allowing air to pass into the nasal cavity • Examples • [國]: [m] 媽, [n̪] 拿, [ŋ] 紅 • [閩]: [m] 媽, [n̪] 貓, [ŋ] 紅 • [E]: [m] my, [n] new, [ŋ] sing
Articulatory phonetics (17) • Fricatives • Process • Airflow is constricted but not cutoff completely • Turbulence is created • Two types • Sibilants: fricatives with high-pitched hissing noise • Nonsibilants: fricatives without high-pitched hissing noise • Examples • [國]: [f] 法, [s̪] 素, [ʂ] 刪, [ʐ] 然, [ɕ] 先, [x] 何 • [閩]: [s̪] 素, [z̪] 熱, [ɕ] 先, [ʑ] 任, [h] 何 • [E]: [f] few, [v] view, [θ] they, [ð] the, [s] sing,[z] zoo, [ʃ] she, [ʒ] garage, [h] high
Articulatory phonetics (18) • Affricates • Homorganic stop + fricative • Examples • [國]: [t̪s̪] 租, [t̪s̪ʰ]粗, [tʂ] 朱, [tʂʰ] 出, [tɕ] 家, [tɕʰ] 恰 • [閩]: [t̪s̪] 租, [t̪s̪ʰ]粗, [tɕ] 一, [tɕʰ] 七 • [E]: [f] few, [v] view, [θ] they, [ð] the, [s] sing,[z] zoo, [tʃ] choice, [dʒ] job
Articulatory phonetics (19) • Approximant • Two articulators are close together but not close enough to cause turbulent airflow • Two types: • Approximant: air flows from the center of the tongue outward • Lateral approximant: air flows from the side(s) of the tongue outward • Examples • [國]: [j] 牙, [w]娃, [ɥ] 圓, [l̪] 來 • [閩]: [j] 厭, [w]歪, [l̪] 來 • [E]: [j] yes, [w] we, [l] like, [ɹ] read
Articulatory phonetics (20) • Tap/flap • A quick motion of the tongue against a hard surface • Examples • [閩]: [ɾ̪]賊仔 • [E]: [ɾ] butter
Articulatory phonetics (22) • Vowels are defined by • Tongue height • Tongue frontness/backness • Roundedness
Articulatory phonetics (23) 意 欲 思 屋 it 矮 黑 可 about bet but bought bat 辦 棒
Articulatory phonetics (24) • Three types of vowels • Monophthongs • A vowel in which the tongue position does not change • Diphthongs • A vowel in which the tongue position changes once • = VG/GV • (ex) [國]: [aɪ] 埃, [eɪ] 黑, [aʊ]好, [oʊ] 候, [ja] 牙,[wa] 娃, [ɥɛ] 約 • (ex) [閩]: [ju] 油 • (ex) [E]: [ɔɪ] boy • Triphthongs • A vowel in which the tongue position changes twice • = GVG • (ex) [國]: [jaʊ] 妖,[jaɪ] 崖, [waɪ] 歪
Articulatory phonetics (25) • Syllable • Consonants and vowels combine to make a syllable
Articulatory phonetics (26) • Phonotactics • Constraints on which phones can follow each other in a language • [國] CCVC: 片 • [閩] CCVC: 接 • [E] CCCVCCC: strengths • [E] CCVCCCC: twelfths
Articulatory phonetics (27) • Lexical stress • A prominent syllable in a word that is determined by the lexicon • (ex) [國] 東西 [ˈtoŋɕi] vs. [ˈtoŋˈɕi] • Three levels • Primary stress: dictionary • Secondary stress: dictionary • Unstressed: dictionary • In unstressed syllables, vowels can be • Reduced: about [ə] • Unreduced: carry
Articulatory phonetics (28) • Sentence stress • = pitch accent • A prominent syllable in an utterance that is determined by pragmatics • (ex) 連站都站不好! • 連戰都站不好!
Phonological categories and pronunciation variation (1) • Pronunciations vary!
Phonological categories and pronunciation variation (2) • Phoneme allophone • /t/ [t, tʰ, ʔ, ʔt, ɾ, t ̚, t̪]
(assimilation) Phonological categories and pronunciation variation (3) • The degree of variation increases with more natural and colloquial speech
Phonological categories and pronunciation variation (4) • Coarticulation • The movement of articulators to anticipate the next sound or persevering movement from the last sound • (ex) nasalization, palatalization, voicing, etc.
Phonological categories and pronunciation variation (5) • Distinctive features • Binary variables which express some generalizations about groups of phonemes • Used to represent each phoneme as a matrix of feature values • Place features • [labial], [coronal], [dorsal] • Manner features • [consonantal], [vocalic], [continuant], [sonorant] • Voicing features • [voice] • Vowel features • [high], [low], [back], [round]
Phonological categories and pronunciation variation (6) • Main use of features • Capture natural articulatory classes of phones • Build articulatory feature detectors and use them to help phone detection
Phonological categories and pronunciation variation (7) • Predicting phonetic variation • Phonological rule • Caveat: • Variation is a stochastic process • Many non-phonetic factors are important to this prediction task
Phonological categories and pronunciation variation (8) • Factors influencing phonetic variation • Non-phonetic • Speech rate • Word frequency • Speaker’s state of mind • Morphological boundaries • Sociolinguistic factors • Phonetic • Intrinsic sound quality • Prosodic boundaries • Coarticulation
Acoustic phonetics and signals (3) • For computers to record and manipulate speech, it is necessary to perform analog-to-digital conversion • A two-step process • Sampling—limit the number of places after the decimal point on the time axis • Quantization—limit the number of places after the decimal point on the amplitude axis
Acoustic phonetics and signals (4) • Sampling rate • Number of sample taken per second • At least two samples per cycle • Nyquist frequency • the highest frequency component that can be captured with a given sampling rate • = ½ sampling rate
Acoustic phonetics and signals (5) Frequency = 100 Hz Sampling rate = 200 Hz Nyquist frequency = 100 Hz
signal not in the original signal aliasing Acoustic phonetics and signals (6)
Acoustic phonetics and signals (7) • Quantization • Analogous to measuring the amplitudes in the waveform with a ruler • The main issue is the accuracy of the amplitude measurements • The most popular choices for the number of bits used to encode speech samples are 8, 12, and 16 bits