2010 IEEE EMBS Conference on Biomedical Engineering & Sciences (IECBES 2010), Kuala Lumpur, Malaysia, 30th November - 2nd December 2010.
Detection of Asphyxiated Infant Cry using Support
Vector Machine Integrated with Principal
Component Analysis
R. Sahak
i
, Y. K. Lee
2
, W. Mansor, A. 1. M. Yassin, A. Zabidi
Facult of Electrical Engineering
Universiti Teknologi Mara, 40450 Shah Alam, Selangor, Malaysia
'rohilahsahak@yahoo.com
'leeyootkhuan@salam.uitm.edu.my
Abstract-Asphyxia refers to respiratory failure in infants, a
condition caused by inadequate intake of oxygen. It is important
to diagnose asphyxia in infants as early as possible, as it could
lead to infant morbidity. PCA has the capability to reduce the
dimension of input feature vector to SVM. Previous attempts
with PCA and SVM to detect asphyxia from baby cries found
their principal components in a random manner, which
consumes tremendous computation effort and time. Our work
here investigates the improvement in performance to detect
asphyxia from infant cries by integrating PCA and SVM with a
polynomial kernel, with principal components being ranked by
EOC, CPV and SCREE methods. Extracted features from the
analysis of MFC coefcients are first ranked with the three
feature selection algorithms of PCA, before being submitted to
SVM for classifcation. Classifcation accuracy and support
vector are employed to gauge the performance. It is found that
the highest classification accuracy and support vector number
from classifcation with support vector machine alone are
93.836% and 335.1, with a second order polynomial kernel and a
regularization parameter of 1 E-04, while those from CPV and
SVM outperformed with CA of 94.172%, a low SV of 254.3, a
third order polynomial and regularization parameter of 1 E-05.
Keywords- Asphyxia, infant cry, principal component analysis,
support vector machine, polynomial kernel
I. [NTRODUCTION
Asphyxia refers to respiratory failure in infants, a condition
caused by inadequate intake of oxygen [I]. [t is important to
diagnose asphyxia in infants at early birth since it is one of the
causes of infant morbidity. [f improper treatment is given to
the infant, hypoxia can happen due to insufcient supply of
oxygen to the brain, organ and tissues. This will lead to
further complications that would result in death.
Previous studies found relationship between infant cry and
asphyxiated infants [2-3]. A classifcation accuracy of 86% in
the detection of asphyxia and deafess was attained with feed
forward input delay neural network [4]. The classifcation
accuracy is found to have improved to 97.4% with the
addition of principal component analysis (PCA) to reduce the
dimension of feature vector [5]. Then, support vector machine
(SYM) and fuzzy support vector machine (FSYM) were
applied to the same classifcation problem, with PCA for
preliminary feature extraction. It is found that FSYM with 10
principal components outperformed SYM to reach a
classifcation accuracy of 94.982% [6]. All the studies above
made use of the transformed coeffcients of infant cry signals
from mel fequency ceptrm (MFC) analysis. However, the
number of principal components for use by the PCA is
selected randomly and hence higher classifcation accuracy is
possible. Besides, this process consumes tremendous
computation time and effort.
Our work introduces and compares three mathematical
approaches to selection of principal components of
signifcance, i.e. eigenvalue-one-criterion (EOC), cumulative
percent variance (CPY) and scree test (SCREE), to make
selection of principal components in a more mathematic and
systematic way, to allow more convincing performance
evaluation at lesser computation time. SYM with polynomial
kernel is used in the fnal stage to classif the cry patterns.
Classifcation accuracy and number of support vector are
adopted as the comparison platform. It is hope that automated
detection of asphyxiated infants fom their cries, once
validated, could help to provide relief to nursing staff in
screening, more timely treatment to needy infants that would
lessen casualties, less calculated risk with more true positives
and true negatives due to fatigue of medical staff.
II. FEATURE SELECTION AND PATTERN CLASSIFICATION
Support vector machine is used to classif normal infants
fom the asphyxiated ones, tracing their cries while principal
component analysis is applied to select feature of signifcance
from the transformed coeffcients. The uniqueness of the
integration of these two techniques to our work being
optimisation of principal components to reduce the dimension
of input feature vector, which comes with the advantage faster
solution at lesser computation effort and time. The following
gives a summarised background theory on the two techniques.
A. Principal Component Analysis(PCA)
Redundant parameter is a common phenomenon of feature
extraction, which results in the presence of features with
minimal signifcance and unnecessary large dimension. PCA
has the advantage of fi ltering for the signifcant features while
fltering off the redundant features. It entails a mathematic
procedure that transforms variables into employment variables
known as principal components (PC). The transform carries
three obvious effects; it orthogonalizes the components of the
978-1-4244-7600-8/10/$26.00 ©2010 IEEE 485