heart sound segmentation: a stationary wavelet transform...
TRANSCRIPT
![Page 1: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/1.jpg)
Heart Sound Segmentation: A
Stationary Wavelet Transform
Based Approach
Author:
Nuno Marques
Advisors:
Rute Almeida
Miguel Coimbra
![Page 2: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/2.jpg)
Classifying Heart Sounds PASCAL
Challenge
The challenge had 2 tasks:
Segmentation and Classification
and Anomaly Detection
This work describes
what i did in the first
task: Segmentation
and Classification
![Page 3: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/3.jpg)
Datasets
iStethoscope Digiscope
Non-controlled
environment
No expert!
Who was
auscultated ?
Controlled
environement
Done by expert!
Auscultation were
performed on
infants exclusively!
44100 Hz
20 auscultations
4000 Hz
80 auscultations
![Page 4: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/4.jpg)
Heart Sounds We want to detect and
distinguish these two
peaks ! (which are the
heart sounds!)
![Page 5: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/5.jpg)
How do you detect and distinguish
heart sounds ?
![Page 6: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/6.jpg)
Heart Sound Segmentation
Cardiac Segmentation algorithms
can be successfully divided
in 4 phases:
Pre-
processing
Representation Classification
Segmentation
![Page 7: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/7.jpg)
Pre-
processing
P
![Page 8: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/8.jpg)
Pre-
processing
P
![Page 9: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/9.jpg)
Pré-
processamento Representation
R
![Page 10: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/10.jpg)
Pré-
processamento Segmentação Representation
R
![Page 11: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/11.jpg)
Pré-
processamento Segmentação Segmentation
S
![Page 12: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/12.jpg)
Pré-
processamento Segmentação Segmentation
S
![Page 13: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/13.jpg)
Pré-
processamento Segmentation
S
![Page 14: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/14.jpg)
Pré-
processamento Segmentation
S
![Page 15: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/15.jpg)
Pré-
processamento Segmentação Classification
S1/S2/sistole/diastole?!
C
![Page 16: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/16.jpg)
Pré-
processamento Segmentação Classification
S1 diastole S2 sistole S1
C
![Page 17: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/17.jpg)
Manual Annotation
P
![Page 18: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/18.jpg)
Manual Annotation
P
![Page 19: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/19.jpg)
Fourier Transform
Mediana1 Mediana2 ... P
![Page 20: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/20.jpg)
Spectral Analysis
P
![Page 21: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/21.jpg)
Pre-Processing
P
Just downsampled iStethoscope!
![Page 22: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/22.jpg)
Representation
R
A good cardiac signal representation
should have 2 characteristics g1 e g2
![Page 23: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/23.jpg)
g1. Accentuate the difference between
S1/S2 and sistole/diastole
R
S2 S1
sistole diastole
![Page 24: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/24.jpg)
g2. Accentuate the difference between
S1 and S2
R
S2 S1
![Page 25: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/25.jpg)
Representation
R
• Shannon Energy Envelope
• Shannon Entropy Envelope
Domínio do
tempo
![Page 26: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/26.jpg)
Shannon Energy Envelope
R
![Page 27: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/27.jpg)
Shannon Energy/Entropy
R
![Page 28: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/28.jpg)
Representations
R
• Continuous Wavelet Transform
• Discrete Wavelet Transform
• Stationary Wavelet Transform
• S-Transform
• Empirical Mode Decomposition
• Hilbert-Huang Transform
Time-Frequency
Domain
![Page 29: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/29.jpg)
Digiscope Results
R
![Page 30: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/30.jpg)
iStethoscope Results
R
![Page 31: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/31.jpg)
Segmentation
S
We can divide the Segmentation phase
into 2 sub-phases:
• Peak Detection
• Boundary Detection
![Page 32: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/32.jpg)
Peak Detection
S
![Page 33: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/33.jpg)
Boundary Detection
S
![Page 34: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/34.jpg)
Convolution
S
![Page 35: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/35.jpg)
Idea!
S
Use a filter in the SWT that looks
like the S1/S2 in order to
determine their boundaries!
![Page 36: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/36.jpg)
Stationary Wavelet Transform
x[n] h1 [n]
g1[n] h2 [n]
g2 [n]
g3 [n]
h3 [n]
Scale 1 Coeffs
Scale 2 Coeffs
Scale 3 Coeffs
gj[n] gj+1[n] 2
hj[n] hj+1[n] 2
Daubechies 38
S
![Page 37: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/37.jpg)
Problem
S
x[n] h1 [n]
g1[n] h2 [n]
g2 [n]
g3 [n]
h3 [n]
Scale 1 Coeffs
Scale 2 Coeffs
Scale 3 Coeffs
Stationary
Wavelet
Transform gj[n] gj+1[n] 2
hj[n] hj+1[n] 2
![Page 38: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/38.jpg)
Problema
S
h10 [n] x[n] g1[n] g9[n] ... ( ) Signal becomes completely deformed!
![Page 39: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/39.jpg)
Solution
S
x[n] g1[n] g9[n] h10 [n] ...
Lets use the Convolution‘s Associative property!
( )
x[n] g1[n] g9[n] h10 [n] ... ( ) =
![Page 40: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/40.jpg)
Solution
S
g1[n] g9[n] h10 [n] ... ( ) x[n]
![Page 41: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/41.jpg)
Signal Transformation: Digiscope
S
x[n] Shannonenergy(x[n])
![Page 42: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/42.jpg)
Signal Transformation: iStethoscope
S
x[n] Shannonentropy(x[n])
![Page 43: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/43.jpg)
Shannon Energy
S
![Page 44: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/44.jpg)
Wavelet Coefficients
S
![Page 45: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/45.jpg)
Inflection Points
S
![Page 46: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/46.jpg)
Segment Descriptors
S
- Maximum
![Page 47: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/47.jpg)
Segment Descriptors
S
- S1/S2 - Sistole/Diastole
![Page 48: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/48.jpg)
S
![Page 49: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/49.jpg)
PASCAL Challenge Results
S
![Page 50: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/50.jpg)
Determining Boundaries
S
![Page 51: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/51.jpg)
Determining Boundaries
• Variation between Segments
• Longest Increasing/Decreasing
Sub-sequence
S
![Page 52: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/52.jpg)
Variation Between Segments(a1)
Maximum length of segment
Minimum length
Of segment
S
![Page 53: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/53.jpg)
Longest Increasing/Decreasing
Sub-sequence(a2)
S
Longest
Increasing
Sub-Sequence
Longest
Decreasing
Sub-Sequence
![Page 54: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/54.jpg)
Baseline Method(a3)
S
Maior
sub-sequência
crescente
Maior
sub-sequência
decrescente
![Page 55: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/55.jpg)
Results
Média +- desvio padrão (ms)
S
![Page 56: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/56.jpg)
Classification
![Page 57: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/57.jpg)
Pré-
processamento Segmentação Classification
S1/S2/sistole/diastole?!
![Page 58: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/58.jpg)
Individual descriptor
C
This segment’s descriptor - Máximo
![Page 59: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/59.jpg)
Expanded Descriptor
C
This segment’s descriptor - Máximo
![Page 60: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/60.jpg)
Combination of descriptors:
Individual
C
This segment’s descriptor - Máximo
![Page 61: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/61.jpg)
Combination of descriptors:
Expanded
C
This segment’s descriptor - Máximo
![Page 62: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/62.jpg)
Results: Combination of
Descriptors
C
![Page 63: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/63.jpg)
Conclusion
![Page 64: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/64.jpg)
Conclusion
• Spectral Analysis
• Evaluation of different types of
Representations
• New peak detection algorithm
• 2 new boundary detection algorithms
• Article publication in Computing in
Cardiology 2013
![Page 65: Heart Sound Segmentation: A Stationary Wavelet Transform ...mcoimbra/lectures/PSI_1314/PSI_1314_NMarques.pdf · Heart Sound Segmentation: A Stationary Wavelet Transform Based Approach](https://reader035.vdocument.in/reader035/viewer/2022062912/5d1cbc0888c993d66e8d7ad5/html5/thumbnails/65.jpg)
Thank you!