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Archives of Business Research – Vol. 9, No.1

Publication Date: January 25, 2021

DOI: 10.14738/abr.91.9612.

Lu, C., Ren, Y., & Han, L. (2021). Face and Ethnical Group Recognition with Images of Different Resolutions. Archives of Business

Research, 9(1). 140-147.

Face and Ethnical Group Recognition with Images of Different

Resolutions

Chong Lu

School of information management,

Xinjiang University of Finance and Economics, Urumqi 830012, China

Yan Ren

School of information management,

Xinjiang University of Finance and Economics, Urumqi 830012, China

Liying Han

School of information management,

Xinjiang University of Finance and Economics, Urumqi 830012, China

ABSTRACT

In this paper, a dataset for Xinjiang minority ethnical groups is

introduced, and implementation of two dimensional Linear

Discriminant Analysis (2DLDA) and two-dimensional Partial Least

Squares (2DPLS) is investigated. Two important topics for face

recognition and the ethnicity recognition are investigated for

database with different image resolutions. Experiments show that

2DLDA performances better than 2DPLS on our face database.

Key Words: face recognition, ethnical group recognition, different

resolution image

INTRODUCTION

Face recognition has been a very popular research topic in computer vision community. A

complete face recognition system includes six steps, data capture [1,2], Image preprocessing [3],

face detection [4], face feature extraction [5], face database comparison [6] and face recognition

[7,8]. The existing facial features include three categories, holistic feature description such as

PCA, LDA, ICA[9,10,11],etc. local feature description such as Gabor, LBP[12,13],etc. and some

fusion features which are obtained by combining holistic feature and local feature Holistic

features[14]. The criterion function of two-dimension LDA (2DLDA) and two-dimension PLS

(2DPLS) have many advantages that can be established with original image covariance matrix

directly instead of undergoing reshaping them to vector, and due to the importance of face

recognition, ethnicity recognition is attracting more attention with broad applications [15,16,17].

In this paper, we will consider both problems with our new dataset created in our lab.

The remainder of this paper is organized as follows: after reviewing existing techniques 2DPLA

and 2DPLS in Section 2, we briefly describe our face database in Section 3, and then discuss

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Archives of Business Research (ABR) Vol 9, Issue 1, January-2021

experimental results in Section 4. In Section 5 experimental evaluations of ethnic identification

has done by 2DLDA algorithm. Last but most importantly, we conclude in Section 6.

2DLDA AND 2DPLS

In this section, we will briefly outline 2DLDA and 2DPLS in order to present the contribution of

this paper clearly.

2DLDA

Let {A$}$&'

( be training images set, where A$ denotes ith an m × n training sample. N is the total

number of training samples, containing C classes, and the ith class C$ has n$ samples, with

∑ n$

0

$&' = N. 2DLDA method tries to find a projected vector x that maximize the following

objective function [17].

J(x) = x6S8x

x6S9x (1)

Where T denotes transpose, S8 and S9 are the between-class scatter matrix and the within-class

scatter matrix, respectively defined as follows.

S8 = <N$(A=$

0

$&'

− A=)6(A=$ − A=) (2)

S9 = <<(A@ − AA = )6(A@

@∈0C

− A$)

0

$&'

(3)

In witch A= and A=$ represent the global and the ith class means defined as follows.

A= = 1

N<<A@

@∈0C

0

$&'

(4)

AA = = 1

n$

<A@ (5)

@∈0C

2DLDA aims to find the optimal projection direction x in order to maximize J(x).

2DPLS

M.L. Yang et al. [18] proposed 2DPLS algorithm for face recognition and we briey describe this

technique here. Let {A$}$&'

( be training images set, where A$ denotes ith an m × n training sample.

N is the total number of training samples, containing C classes, and the ith class C$ has n$ samples,

with ∑ n$

0

$&' = N. Thus, we can obtain the mean matrix of samples matrix.

A= = 1

N<<A@

@∈0C

0

$&'

6

To finish image recognition task, sample images can be considered as a variable set in 2DPLS,

called sample matrix. Another variable set is class membership matrix, which represents the

relationship between samples and classes. It is similar to the definition in traditional CCA and in

PLS, the class membership matrix can be coded as follow [19]

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URL: http://dx.doi.org/10.14738/abr.91.9612. 142

Lu, C., Ren, Y., & Han, L. (2021). Face and Ethnical Group Recognition with Images of Different Resolutions.. Archives of Business Research, 9(1).

140-147.

Z = J

P' 0M

0' PM

... 00

... 00

⋮ ...

0' 0M

⋱ ⋮

... P0

Q

(R×0)×(S×()

(7)

Where P$ means there are n$ samples in the ith class, but each sample here is corresponding to a

matrix QR×S as large as the size of sample image. So the matrix P$ can be denoted as P$ =

[Q,Q, ... Q]R×(S×SY),

i = 1 ... . C. For obtaining the mean of class membership matrix in the sense of

two dimensional sample representation, the matrix Y is rewritten as Y = [y',', ... , y',SY], then the

covariance matrices of A and Y are denoted as

G^ = 1

N<<(A$,@ − A=)

@∈0C

(A$,@ − A=)6 (8)

0

$&'

G` = 1

N<<(y$,@ − Y=)

@∈0C

(y$,@ − Y=)6

0

$&'

(9)

G^` = G`^

6 = '

( ∑ ∑@∈0 (A$,@ − A=) C (y$,@ − Y=) 0 6

$&' (10) respectively.

FACE DATABASE CREATION

In this section, we present our face database creation. We captured face images for six different

minority nationality groups which are Kazak, Uygur, Kirgiz, Mongolian, Sibbo and Hui with

different pixel resolution cameras, i.e., Hasu, Nikon D90, Nikon S60 and Kinect. Face Database

contains eight different images of each of 48 distinct subjects. For some subjects, the images were

different with varying the lighting, facial expressions and facial details with glasses. All the images

were taken against a light homogeneous background with the subjects in an upright, frontal

position. they are shown below.

The size of Each Image in the Original Face Database captured with Hasu camera is about 41M

with12840 × 10550 pixel, Nikon D90 is about 5.4M with4280 × 2580 pixel, Nikon S60 is about

3.1M with30100 × 2100 pixel and Kinect is about 8K with200 × 160 pixel.