Soft Biometrics in Face Recognition


30 Νοε 2013 (πριν από 4 χρόνια και 5 μήνες)

64 εμφανίσεις




Soft Biometrics in Face Recognition

Zhi Zhang

1. Project Description

This project is designed to apply “soft” biometrics in the field of face recognition. The
basic idea is to extract some “soft” biometric traits from the given images to build and

the performance of the face recognition system. Also these “soft” biometric
traits can also be applied to other fields like management of the facial image database,
gender classification system, ethnic classification system or age estimation system.

ft” biometric traits including gender, ethnic, color information of the features like
eyes, hair, facial skin, etc. In the processing of a given image, we first collect these traits
as a guidance. For the identification system, this process could greatly r
educe the amount
of computation needed. Extraction and comparison of these traits could also simplify the
processing of the verification system.

Due to the intrinsic features of these “soft” biometric traits, color information is definitely
necessary for

this project. We could use color facial image databases from other institutes
or build our own database. But for the current phase, only a small image database is
enough, which could be facial images from the internet and most of them are color
images. .

Another important part of this project is to propose a new approach of face recognition
based on the concept of “soft” biometric traits.

2. Divisions of the Project

Based on the description of the project, we could divide the project into several sub

Key Feature Points Extraction

Feature Selections

“Soft“ Biometric Traits Extraction

“Soft” Biometric Traits Classification

Face Recognition

I am working on the background research on the subject of soft biometrics in face
recognition in the las
t week. Although “soft” biometrics is a new concept in the field of
pattern recognition, especially in the field of face recognition, there had been a lot of
work on parts of the subject. For example, there has been some research on gender
ethnic classification and even age estimation. But still, most of these works
had been on the grey scale images. The similar work on color images is still on demand.

The other part of my work is on the eigenfaces. Eigenfaces were first proposed by
w Turk and Alex Pentland in the Media Laboratory in MIT in 1991. I have studied
their very first paper on eigenfaces, named “Eigenfaces for Recognition” on the Journal




of Cognitive Neuroscience. The principle of this approach is not hard to understand. It
“treats the face recognition problem as an intrinsically two
dimensional (2
D) recognition
problem rather than requiring recovery of three dimensional geometry”. Based on
principal component analysis, this approach projects face images into a much smaller
feature space. The feature space is the composed by eigenvectors of the set of face
images. The amount of computation needed to find those eigenvectors are reduced by a
method proposed in that paper. Those extracted features(eigenvectors or eigenfaces)
ld be used to classify a face image and also could be used to locate and detect faces in
given images. The paper indicates that systems based on that approach could be running
in “near
real time in a reasonable unstructured environment”. Because of the int
algorithm of this approach, there are for sure to be some defects. Because it processes the
whole image, including the facial part and also the background part, this algorithm is
sensitive to the variations of the background, the scale of the facial

part and also the
luminance variance. And also, it is sensitive to the head orientation because this
algorithm only works for the front view of faces, more specifically front up
straight view
of faces. When the volume of the image database increases, the
performance of the
system would decreases. Anyway, eigenfaces is a milestone in the field of face
recognition, a lot of work has been done to improve its performance since 1991. It is still
a feasible approach and one of the most used approach in this fiel
d. Studying this method
is a good starting to my project.

3. Innovations

Most of the current face recognition systems work on the gray scale images.
is still the most used approach in the field of 2
D face recognition. Robust and efficient
proaches in face recognition are still not available.
Although quite some work has been
done on the fields like gender classification, ethnic classification, age estimation,
researches on these fields are still on demand. The proposal of applying “soft” bi
traits into the field of face recognition is still a
novel concept.
A lot of work could be
done on this exciting field.

I am thinking of working on both color images and grey
scale images. For some parts of
the problem, like extracting the color
of the eyes, color of the hair and color of the skin,
we should work on the color images. But for other part of the work, especially for the
most of the preprocessing work, like the face extraction and tracking, the key points
extraction and the geometric
features extractions, it would be more efficient if working
on the grey scale images. But also, I find that color information could be helpful in these
preprocessing works. There could be a trade
off of the efficiency and the accuracy of the
system. And al
so color information is vulnerable to the variations of luminance. Under
different lamination, the same object could be in different colors.