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:

. .

info.kutub.www

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,

... ,

.....

XP

.....

:

(Computer Science -1 CS)

(Information System -2 IS)

: ((CS

( (Image Processing

( (Speech Processing

((Speech Processing

) ( ((speech recognition

: ((Speech

: ((voice.

1000

.

.

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( )

.

((speech recognition .

((speech recognition system :

3 :

1- Pre-processing

2- Recognition

3-Communication

Pre-processing

((Recognizer

(( s/w & h/w ((Recognizer

h/w s/w

. Pre-processing

Analog signal

-: Continuous Signal

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.

discrete signal :

binarydigital signal discrete signal form

Quantization

((threshold ((2level :

(Discrete Signal ((Analog Signal )

((Quantization ( (Processing

.

....

, Amplitude : amplitude amplitude .....

....

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level threshold * threshold

.... thresholdimage threshold

(Speech Recognition System )

: pre-processing - recognition - communication

((analog signal pre-processing 0 , 1 (digital signal) ...............

recognition:

:

(identification & verification)

verificationidentification

: identification

,x x x

x

x Distance measurement x

.. x

Distance measurement identification

x .. x verification

verification x ( x

recognition Communication

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Communication:

H/WS/W :

Security ,

" " " "

!! security

white noise

. noise

:: noise

education speech ..

control ..

Diagnosis ..

Bio informatics

speech processing ,,,

.... image processing

pre-processing , recognition , communication :

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..

..

.pre-processing :

((Data collection & acquisition /1

..

((voiced & unvoiced detection 2/

...

amplitude ),,(

),(

noise

Unvoiced Voiced Zero Crossing

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voiced

amplitude

" horizontal access "

zero crossing , zero

voiced speech Zero Crossing

unvoiced

, amplitude

...... zero crossing

end -point-detection /3

Processing noisesignal

noise filter noise ...

4/WrappingTime

( ) :

............ algorithm

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Framming /5

. 20

, ) )20 speech )20 frame frames speech

frame ((sampleframe ) frame

.processing

frames .... ..........

Windwing/6 .....frames

frame frame window

50% frame 50% 50%windows --:

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7/Modeling

Analog Signal Speech Signal features modeling .....

Feature extraction 8/

modeling ...

..........

:

isolated word recognition I W R co-articulation

..

connected word recognition C W R .. Stops

continuous speech recognition C S R

..

Speech understanding S U ..

speaker identification ,speaker verification S I, S V .

word spotting w s key word

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...................

neural signal Waveform gestures

.. .utterance

Waveform(speech).., Waveform

Energy time Waveform.Amplitude

spectrum Amplitude frequencies :

. processing

time:3 Spectrogram frequencyamplitude wave.

utterance

vocal folds or vocal cords vocaltract

oral cavity

-

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nasal cavity .Acoustic wave form

Waveform acoustic

.

.

3 vocal apparatus Throat mouthnose

. vocal cords throat

:

velumTongueteeth: Hard palate: roof of the mouth alveolar

lips

.

periodic voiced

.

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quasi periodic voiced

like periodic: noise

randomnoise

:

.

:

3 .

voiced sound 1

frequency

:

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: frequency

:

.. :

.. :

400 - 60 .100 180

unvoiced sound 2

voiceless sound noise

.

3 ....

:

Glottis ....

:

phoneme .

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linguistics ... phoneme

.....

phonetics ...

voiced

.unvoiced

.

consonantvowel

vowela, e ,u , o , aa ,ee , au ,uh

consonant .

consonant

place of articulation 1

..

articulationmanner of 2

:

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plosive G bid B

gate :

Fricatives

:

v , th , z, f, s, sh

Nasals m, n, ng nasal cavity.

Affricates Judge J

Approximant :

semivowels W, Y

Liquids R, L