Phonetics%20

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Phonetics Phonology

• William Barry

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What is phonetics

• The observation of how people say things.
• The description of spoken language atthe level
  of "pronunciation"
• The measurement of pronunciation events
• The modeling of pronunciation behaviour
• The explanation of the communicative contribution
  of pronunciation patterns.

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Areas of phonetics

• Speech production(what do the speech organs do?)
• Speech acoustics(what does the resulting speech
  signal look like?)
• Speech perception(What are the acoustic
  properties that cause us to hear what we hear?)

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Speech production levels

• Respiration (sub-glottal activity)How do we
  control our breathing to help our speech
  communication?
• Phonation (glottal/laryngeal activity)How do we
  control our vocal-folds to help our speech
  communication?
• Articulation (supra-glottal activity)How do we
  control our articulators to help our speech
  communication?

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Speech production analysis

• We make recordings (of course ? )- we choose the
  type of speech- we choose the type of speaker-
  we choose the type of signal
• These choices determine our analysis- speech
  type (basic sound types, precise vs. casual
  speech monologue vs. dialogue behaviour)-
  speaker type (e.g., regional vs."standard"
  speakers ) - signal type (acoustic
  microphone physiological electro-myographic
  neurological .......)
• Signal type dictates the experimental set-up-
  Only the acoustic signal allows natural"
  recordings

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A standard text .....

• The North Wind and the Sun
• The North Wind and the Sun were disputing which
  was the stronger, when a traveler came along
  wrapped in a warm cloak.They agreed that the one
  who first succeeded in making the traveler take
  his cloak off should be considered stronger than
  the other.Then the North Wind blew as hard as he
  could, but the more he blew the more closely did
  the traveler fold his cloak around him and at
  last the North Wind gave up the attempt. Then the
  Sun shined out warmly, and immediately the
  traveler took off his cloak. And so the North
  Wind was obliged to confess that the Sun was the
  stronger of the two.
• (see www.coli.uni-saarland.de/elaut for other
  languages)

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For signal analysis

• Popular analysis packages
• Praat (www.praat.org) (by Paul Boersma David
  Weenink, Phonetics Amsterdam)
• Wavesurfer (www.speech.kth.se/wavesurfer/)(by
  scientists at Stokholm Technical University -
  KTH)
• Goldwave (www.goldwave.de)(commercial program,
  but available free for trial use)

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Speech production Speech Sounds

• E.g. What are the vowels of English and German
  like?
• The cat sat on the matSBE ?? US ??
  German ??
• The computer is broken. SBE ?? US ??
  German ??
• Can you hear the differences?
• Can you describe the differences?
• Can you say why there are differences?

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Vowel quality and symbols
German
English
?i?
I
?e
(E?)
??
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Speech production Speech Sounds

• E.g. What are the consonants of English and
  German like?
• The cat sat on the matSBE ?? US ??
  German ??
• The computer is broken. SBE ?? US ??
  German ??
• Can you hear the differences?
• Can you describe the differences?
• Can you say why there are differences?

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Speech production symbols sounds
Consonant articulation

• Place
• lips (labial)
• teeth (dental)
• alveolar ridge (alveolar)
• hard palate (palatal)
• soft palate (velar)
• uvula (uvular)
• pharynx (pharyngeal)
• larynx/glottis (glottal)

• Manner
• stop/plosive
• fricative
• nasal
• lateral
• glide/approximant
• trill
• tap/flap

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Speech production symbols again

• IPA table

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Speech production Intonation

• (Intonation can have a syntactic or pragmatic
  function)
• Statement Question (sentence modality)
• Scotland beat France at rugby.
• Scotland beats France at rugby?
• Request Command (pragmatic function)
• Could you come to my office?
• Could you come to my office?

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So whats "Phonology?

• The systematic use of sound segments and prosody
  in a specific language
• Examples
• German has vowels a, b, c, d, f ..... English
  has a, c, e, .....
• German has final devoicing of obstruents
• The 'voicing' of English plural genitive s
  and past tense d follows the preceding sound
• Stress falls on the first element in compound
  words in German (in English the second element is
  often stressed) Compare English vs.
  German(Eng.) ?Buckingham ?Palace, ?Albert
  ?Hall, ?National ?Gallery

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and Perception?

• Interesting facts We dont identify the
  individual sounds as they reach our ears.The
  syllable (cons) vowel (cons) is probably the
  smallest unit of perception.
• The consonants by themselves contribute less
  than the vowels by themselves to our
  understanding of a spoken utterance (because they
  dont form syllables!).(but they contribute more
  to the understanding of an utterance if there is
  one unchanging vowel than the vowels do with one
  unchanging consonant!)
• And what about written consonants and vowels?

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Consonants vs. vowels 1

• __e _ea_e_ _o_e_a__ _o_ _o_o__o_
  _a__e_ __ou_y i_ __e _o__i__ _i__
  a _e_ _u__y __e___ i_ __e
  a__e__oo_.

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Consonants vs. vowels 2

• Th_ w _th_r f_r_c_st f_r t_m_rr_w
  r_th_r cl __d_ _n th_ m_rn_ng w_th _
  f_w s_nn_ sp_lls _n th_ _ft_rn__n.

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Consonants vs. vowels 3

• The weather forecast for tommorow rather cloudy
  in the morning with a few sunny spells in the
  afternoon.

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Consonants vs. vowels 4

• The weather forecast for tommorow rather cloudy
  in the morning with a few sunny spells in the
  afternoon.
• speech versions
• only consonants
• only vowels
• original

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Consonants vs. vowels 5

• The vowel information is greater, but we need the
  temporal pattern (the rhythm) of the utterance
  (a product of the syllable structure (cons
  vowels)and the duration/weight/prominance of the
  vowels.
• only vowels without silences
• only vowels with silences
• only vowels monotonous

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So we perceive in chunks

• The syllables are the (more prominent) vowels
  with the (less prominent) consonants around them
• The sentences are the chains of syllables,with
  the more prominent words (the lexical or content
  words) giving the content and the less prominent
  words (grammatical or function words) grouped
  around them, showing the relation between them
• The melody (intonation pattern) helps to make the
  important words more prominent.

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Connected speech

• "The president will be elected for a period of
  four years."
• Natural connected speech
• as chain of isolated words (no reductions)
• Natural with silences between words
• as chain of isolated without silences
• Comparison of isolated vs. connectedfunction
  words

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Connected speech (summary)

• "The president will be elected for a period of
  four years."
• The content words are longer, louder,unreduced,
  comprehensible when excised.
• The grammatical words are shorter, lessloud,
  strongly reduced, incomprehensiblewhen excised.
• The production effort we invest reflects the
  importance of the words (longer louder
  unreduced more care and effort).
• Our perception strategies follow this unequal
  distribution of effort. We concentrate on the
  prominent words.(BUT Careful! This is a
  strategy associated with certaintypes of
  languages stress-timed languages.Not all
  languages do this. So-called syllable-timed
  languages are less stress oriented.)

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So, what applications are there?

• We dont normally think about pronunciation. So
  understanding the mechanisms of speech is
  invaluable in
• foreign language teaching/learning
• pronunciation dictionaries
• speech pathology
• forensic phonetics
• speech technology

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Lets look briefly at speech synthesis

• Commercial systems use "concatenative"
  methods(they stick recorded bits of speech
  together)
• They dont need very much phonetic knowledge
  (but they need to have good selection
  strategies) and the same approach can be applied
  to many different languages.
• The systems are good in limited domains, and
  using a neutral speaking style. They are bad
  on wide-ranging topics and more expressive
  speech.
• Research systems, such as "articulatory
  synthesis" require a lot of knowledge, and are
  used to find out more about speech production.
• They are potentially very flexible (so the
  developer has to know how to constrain the
  system just to produce what is natural)
• They are much more complex, and have to be
  programmed for each new language on the basis
  of knowledge acquired about that language.

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Speech synthesis

• A locally developed product (and research
  platform)
• "Mary" http//mary.dfki.de
• Now a (staged) example of how unexpressive
  synthesis in an inflexible dialogue system can go
  wrong (German railway timetable inquiry system)
• Synthesis Recognition Dialogue?
• (or chaos?)