Eigenphases for Corrupted Face Images
Naser Zaeri
Electrical Engineering Dept., Kuwait University, P.O. Box 5969, Safat 13060, Kuwait
zaery@eng.kuniv.edu.kw
Abstract—Corrupted face image is one of the important
obstacles that machine vision systems encounter when
trying to recognize faces. In this paper, we propose a new
face recognition system that can deal with the problem of
corrupted images more efficiently. The new technique
applies the principal component analysis to the phase
spectrum of the Fourier transform of the covariance
matrix constructed from the MPEG-7 Fourier Feature
Descriptor vectors of the images. It will be shown that the
proposed technique increases the face recognition rate
when applied to images of low resolution and corrupted
by noise, compared to other known methods.
I. INTRODUCTION
In the last few years, researchers in the area of face
recognition have proposed many numerous techniques that
achieve high recognition rate [1, 2, 3]. Despite the significant
advances in face recognition approaches, it has yet to achieve
levels of practicality required for many commercial and
industrial applications. With the increased commercial
interest in portable devices and with the advanced real-time
face recognition systems, the need for more practical and cost
effective systems has increased. For example, in surveillance
systems face recognition plays an important role for reliable
security issues. In such systems, the acquired images may be
challenging as they suffer from noise and being of bad
quality. Further, most of these images look corrupted and not
in an acceptable shape for most of the existing machine vision
systems. In this paper, we describe a new approach for face
recognition system that can be implemented on such bad
quality and destroyed images. It will be shown that the new
technique provides improvements of the performance of the
face recognition rates when compared to other approaches
such as the fisherface LDA method, the direct eigenphase
implementation method to the face space [4], and the PCA
method. This work is organized as follows. Principal
component analysis is described in brief in section 2, as it is
used as part of our scheme. Another brief description of
MPEG-7 Fourier Feature descriptor is given in Section 3. The
formulation of the proposed technique is presented and
discussed in Section 4. In Section 5, results of testing and
implementing the new technique on the xm2vts database
are presented. Concluding remarks are given in Section 6.
II. PRINCIPAL COMPONENT ANALYSIS
The PCA technique, proposed by Turk and Pentland
[1], extracts the relevant information in a face image,
encodes it as efficiently as possible, captures the
variation in a collection of face images, and compares
one face encoding with a database of models encoded
similarly. The images of faces, being similar in overall
configuration, will not be randomly distributed in the
huge image space and, consequently, they can be
described by a relatively low dimensional subspace.
This process is achieved by finding the principal
components of the distribution of faces, or the
eigenvectors of the covariance matrix of the set of face
images. The eigenvectors are ordered, each one
accounting for a different amount of the variation among
the face images. These eigenvectors can be thought of as
a set of features that together characterize the variation
between face images. Each image contributes more or
less to each eigenvector, so that the eigenvector is
displayed as a sort of ghostly face which is called an
eigenface. Example of some of the images used from the
xm2vts database and some of the resultant eigenfaces
using the PCA is shown in Figures 1 and 2, respectively.
Fig. 1. Examples from the xm2vts database.
ACTEA 2009 July 15-17, 2009 Zouk Mosbeh, Lebanon
978-1-4244-3834-1/09/$25.00 © 2009 IEEE 537