In The Name of God The Compassionate

The Merciful

Wavelet applications for

Larynx Disorders Diagnosis

IntroductionWhat is Larynx?

Speech

How do we speak?

Speaking is made up of two mechanical actions called Phonation and Articulation

Common Larynx Disorders Muscle Tension Dysphonia

(MTD)

Vocal Tremor

Vocal Fold Paralysis

Other Common Disorders Laryngeal Cancer

Edema Nodules Polyp

Voice Characteristics

Amplitude Frequency Energy Entropy Fractal Dimension

Amplitude

Maximum amplitude to Minimum amplitude ratio

Energy

Total Energy

Energy in Frames

2)(

1 n

nxN

energy

NwN

Nnw

i

i

nxN

ienergy2

)(1

)(

Energy Application

Total Energy Noise Test Signal to Noise Ratio( Future Use)

Energy in Frames Recording Environment Characteristics

Entropy

Shannon Entropy

p-Norm Entropy

log-Energy Entropy ✓

n

pnxxentropy )()(

n

nxxentropy 2)(log)(

22 )(log)()( nxnxxentropyn

Fractal Dimension

N∆ is the number of times the signal sign is changed.

)4.0

(log)(log

)(log

1010

10

Nnn

n

nD

Signal

The main signal is a 3-second .wav file in which the user simply says “a”

Basic Process

1- Chopping the Signal between two points

2- Segmenting the Chopped Signal

FIR Filters

x(n)

y(n)

Z-1 Z-1 Z-1

gain

x(n-1) x(n-k)x(n-(N-1))

a0 aka1 aN-1

++ +

1

0

)()()(N

k

kaknxgainny

Filters CoefficientsMATLAB Coefficients for db4 Simply Type:

fname=‘db4’;

LP=dbwavf(fname)

HP(k)=(-1)k×LP(K-1-k)

WLP(k)=LP(K-1-k)

WHP(k)=HP(K-1-k)

Wavelets

What are Wavelets?

Wavelets are mathematical functions that

cut up data into different frequency components,

and then study each component with a resolution matched to its scale.

Wavelet Packets

Wavelet packets are particular linear combinations of wavelets.

Applied Wavelet Packet

Input Signal

DownSample

DownSample

DownSample

DownSample

DownSample

DownSample

LPF

HPF LPF

HPF

HPF

LPF

Feature Extraction

EnergyEntropyFractal Dimension

Applied Wavelet Packet

Input Signal

DownSample

DownSample

DownSample

DownSample

DownSample

DownSample

LPF

HPF

LPF

LPF

HPF

HPF

Best Features Vectors

0 to 31 32 to 47 48 49 50Members

0 to 31

Band 6

Entropy

Members

16 to 31

Band 5

Entropy

Total Fractal Dimension

First Band,

Branch 0

Fractal Dimension

First Band,

Branch 1

Fractal Dimension

Diagnosis Block

W and B are generated from Genetic Algorithm methods

BXWY

1

Y

Y

e

eP

Test Program (Normal)

Test Program (Pathologic)