Age Classification Based On Integrated Approach

Автор: Pullela. SVVSR Kumar, V.Vijaya Kumar, Rampay.Venkatarao

Журнал: International Journal of Image, Graphics and Signal Processing(IJIGSP) @ijigsp

Статья в выпуске: 6 vol.6, 2014 года.

Бесплатный доступ

The present paper presents a new age classification method by integrating the features derived from Grey Level Co-occurrence Matrix (GLCM) with a new structural approach derived from four distinct LBP's (4-DLBP) on a 3 x 3 image. The present paper derived four distinct patterns called Left Diagonal (LD), Right diagonal (RD), vertical centre (VC) and horizontal centre (HC) LBP's. For all the LBP's the central pixel value of the 3 x 3 neighbourhood is significant. That is the reason in the present research LBP values are evaluated by comparing all 9 pixels of the 3 x 3 neighbourhood with the average value of the neighbourhood. The four distinct LBP's are grouped into two distinct LBP's. Based on these two distinct LBP's GLCM is computed and features are evaluated to classify the human age into four age groups i.e: Child (0-15), Young adult (16-30), Middle aged adult (31-50) and senior adult (>50). The co-occurrence features extracted from the 4-DLBP provides complete texture information about an image which is useful for classification. The proposed 4-DLBP reduces the size of the LBP from 6561 to 79 in the case of original texture spectrum and 2020 to 79 in the case of Fuzzy Texture approach.

Еще

Age classification, Combined feature, Distinct-LBP, Fuzzy Texture, GLCM, Patterns

Короткий адрес: https://sciup.org/15013309

IDR: 15013309

Текст научной статьи Age Classification Based On Integrated Approach

Published Online May 2014 in MECS DOI: 10.5815/ijigsp.2014.06.07

AGE-CENTERED COMPUTING (ACC) has long been an extensively interesting topic in both Human– Computer Interaction (HCI) and cognitive studies. The human traits displayed by facial attributes, such as personal identity, facial expression, gender, age, ethnic origin, and pose. Recently Human age classification has become an active research topic in computer vision because of its widespread potential real world applications such as electronic customer relationship management (ECRM) [1], security control and surveillance monitoring [2, 3, 4], biometrics [5], and entertainment. There are two fundamental problems in designing the techniques i.e face image analysis and face image synthesis. In both cases Age of face has also been considered as an important semantic or contextual cue in social networks [5] [6]. And age, is an information source for ACC, conveys significant nonverbal information for the communication and interaction between humans or between human and machine. Theoretically, Human Aging can be categorized into many phases as age between 1 to 10, 11 to 20, 21 to 50, 51 to 60 and above 60.Computationally, an age estimation system usually consists of two modules: image representation and age estimation. Age image representations include the anthropometric model [7, 8], wrinkle model [10], active appearance model (AAM) [9], AGing pattErn Subspace (AGES) [11, 12], age manifold learned from raw images [13, 14], local binary pattern features [15], and parts [7] or patch-based appearance model [16, 17]. Given a representation, age estimation can be viewed as a multiclass classification problem [18, 19, 20] or a regression problem [12, 22, 21, 13] or a hybrid of the two [24]. This age estimation method includes single age estimation, age group estimation and hierarchical estimation.

The present paper is organized as follows. The section 2 describes methodology, section 3 and section 4 describes results and discussion and conclusions respectively

  • II.    Methodology

The present paper derived age classification based on the features derived from Grey Level Co-occurrence Matrix (GLCM) on 4-DLBP’s. Most of the statistical methods [25, 26] suffer from the generalization problem due to the unpredictable distribution of the face images in real environment, which might be far different from that of the training face images. The structural method like LBP suffers from illumination effect. To avoid these problems, the present research combined structural and statistical methods based on 4-DLBP using GLCM features. The proposed method consists of nine steps described below.

Step 1 : Take facial image as Input Image (Img).

Step 2 : Convert the RGB image into Grey scale Image by using HSV colour model.

Step 3 : Convert each 3×3 window of facial image into LBP based on the following equation.

(0 if ХИО )

™ = |1 if X^lj f"r Ц = 1'2'3     (1)

Where V 0 is the mean of the 3×3 sub matrix.

Step 4: Convert each 3×3 LBP-window of facial image into four distinct patterns based – LBP’s, named as Left Diagonal (LD-LBP), Right diagonal (RD-LBP), vertical centre (VC-LBP) and horizontal centre (HC-LBP), which are shown in Fig.1. All the four LBP’s contains three pixels only.For all the LBP’s the central pixel value of the 3 x 3 neighbourhood is significant. That is the reason in the present research LBP values are evaluated by comparing all 9 pixels of the 3 x 3 neighbourhood

VC-

LBP

HC-

LBP

Fig 1: Four Different Patterns of LBP.

Step 5: Calculate the LBP unit values for LD-LBP, RD-LBP, VC-LBP and HC-LBP. Each of them will have LBP-value ranging from 0 to 7.

Step 6: Based on the step 5 the present paper divided the LBP units in to two categories i.e Diagonal and Horizontal Vertical (HV) as given in equation 2 and 3 respectively.

Diagonal-LBP (DLBP) = LD-LBP+ RD-LBP (2)

HV-LBP (HVLBP) = VC-LBP + HC-LBP     (3)

Step 7: Generate the co-occurrence matrix based on values generated in step 6. The proposed GLCM is constructed on the proposed Diagonal and HV-LBP (D-HV-LBP) by representing the DLBP values on X-axis and HVLBP values on Y-axis as shown in Fig.2(c). This GLCM is named as D-HV-LBP-GLCM. The D-HV-LBP-GLCM has the elements of relative frequencies in both DLBP and HVLBP as in Fig.2 (a) & (b). The values of DLBP and HVLBP ranges from 0 to 14. Thus the D-HV-LBP-GLCM will have a fixed size of 14 x 14.

(a)                                                (b)

0

1

2

.

.

.

14

0

1

2

.

.

14

(c)

DLBP

Fq1

0

1

2

.

.

.

14

HVLBP

Fq2

0

1

2

.

.

.

14

Step 8: From this D-HV-LBP-GLCM, a set of Haralick features i.e. energy, contrast, Homogeneity and correlation as given in equation 4, 5, 6 and 7 respectively.

Energy = £ ^-1п(р)2(4)

Contrast = Z^ p (i - j)2(5)

Homogenity = £ ^Z i^7)7

Correlation = £ ^ p (LJijL-E)(7)

Where P ij is the pixel value of the image at position (i, j), ц is mean and о is standard deviation.

Step 9: By using K-nn Classifier on the proposed D-HV-LBP-GLCM features, the facial image is classified as one of the category (Child age (0-15), Young Age(16-30), Middle Age(31-50) and Senior Age(>50).

  • III.    Results and Discussions

    The proposed scheme established a database from the 1002 face images collected from FG-NET database, 500 images from Google database and other 600 images collected from the scanned photographs. This leads a total of 2102 sample facial images. In the proposed D-HV-LBP-GLCM method the sample images are grouped into four age groups of Child age(0-15), Young Age(16-30), Middle Age(31-50) and Senior Age(>50). A few of them are shown in Fig.3. The Contrast, Correlation, Energy and Homogeneity features are extracted from D-HV-LBP-GLCM of different facial images and the results are stored in the feature database. Feature set leads to representation of the training images. The Contrast, Correlation, Energy and Homogeneity features derived from D-HV-LBP-GLCM of four age groups of facial images are shown in tables 1, 2, 3, and 4 respectively. To evaluate the proposed method, 30 different facial expressions are considered from FG-NET aging database, Google database and scanned images as a test data base. The present paper estimated distance between feature database and test database by using Euclidian distances. To classify the test images into appropriate age group the present paper utilized minimum distance K-nearest neighbour classifier. Successful classification results of test data bases for the proposed D-HV-LBP-GLCM method are shown in table 5.

Fig.3: FG-NET aging database: 011A07, 011A05, 010A10, 010A09, 010A07b, 001A14, 019A07, 009A14, 009A13, 009A11, 008A16, 008A13, 010A05, 010A04, 010A01, 009A09, 009A05, 004A21, 002A29, 002A26, 002A23, 002A21, 001A29, 001A28, 001A22, 009A22a, 008A21, 004A28, 004A26, 006A36, 005A40, 011A40, 001A43b, 002A31, 001A33 007A37, 005A52, 005A49, 004A53, 004A51, 048A54 , 006A61, 005A61, 004A63.

Table 1: Feature set values of d-hv-lbp-glcm for child age images.

S

No

Image Name

Contrast

Correl-tion

Energy

Homo

Geneity

1

001A05

7.20958

0.68932

0.02766

0.49165

2

001A08

7.18185

0.70819

0.02699

0.50230

3

008A12

7.06797

0.68230

0.02975

0.49620

4

001A14

7.27466

0.67894

0.02677

0.49043

5

001A02

7.47466

0.81932

0.02779

0.48165

6

001A10

7.00958

0.83819

0.02732

0.51230

7

002A04

7.16797

0.81230

0.02837

0.48730

8

002A05

6.98185

0.80894

0.02632

0.48120

9

002A07

7.28185

0.80932

0.02666

0.47543

10

002A12

7.07466

0.82819

0.03025

0.50165

11

002A15

7.26797

0.80230

0.02716

0.48620

12

009A00

7.13185

0.79894

0.02599

0.46665

13

009A01

7.15958

0.67230

0.02749

0.48043

14

009A03

7.01797

0.66894

0.02729

0.50620

15

009A05

7.22466

0.66932

0.02649

0.47665

16

009A09

7.10958

0.68819

0.02816

0.47120

17

009A11

6.96797

0.66230

0.02782

0.49230

18

009A13

7.17466

0.65894

0.02829

0.50043

19

009A14

7.37466

0.69819

0.02737

0.47730

20

010A01

7.30958

0.67230

0.02727

0.46543

21

010A04

6.86797

0.70032

0.02887

0.49620

22

010A05

7.38185

0.71919

0.02875

0.47337

23

010A06

7.03185

0.69330

0.02682

0.47071

24

010A07a

7.05958

0.68994

0.02577

0.46806

25

010A07b

6.91797

0.69032

0.02925

0.46541

26

010A09

7.12466

0.70919

0.02679

0.46275

27

010A10

7.32466

0.68330

0.02787

0.48262

28

010A15

7.25958

0.67994

0.02627

0.46010

29

011A02

6.81797

0.67932

0.02681

0.45744

30

010A12

7.33185

0.69819

0.02556

0.45479

Table 2: Feature set values of d-hv-lbp-glcm for young age images.

Sno

Image Name

Contrast

Correlati on

Energy

Homogeneity

1

001A16

7.3658

0.7331

0.0258

0.4970

2

001A19

7.5204

0.7218

0.0259

0.4937

3

001A29

7.5762

0.6780

0.0261

0.4966

4

002A16

7.5262

0.7082

0.0263

0.4970

5

001A18

7.2458

0.7196

0.0258

0.4950

6

001A22

7.4004

0.7055

0.0250

0.4947

7

001A28

7.4562

0.6530

0.0277

0.4919

8

002A18

7.2791

0.7446

0.0284

0.4929

9

002A20

7.4338

0.7305

0.0263

0.4970

10

002A21

7.4896

0.6780

0.0268

0.4970

11

002A23

7.3991

0.7071

0.0266

0.4967

12

002A26

7.5538

0.6930

0.0282

0.4960

13

002A29

7.6096

0.6405

0.0263

0.4964

14

004A19

7.3958

0.7696

0.0282

0.4967

15

004A21

7.5504

0.7555

0.0261

0.4959

16

004A26

7.6062

0.7030

0.0279

0.4949

17

004A28

7.5158

0.7446

0.0255

0.4959

18

004A30

7.6704

0.7305

0.0253

0.4944

19

005A18

7.7262

0.6780

0.0258

0.4990

20

005A24

7.1958

0.6696

0.0260

0.4972

21

005A30

7.3504

0.6555

0.0255

0.4979

22

006A24

7.4062

0.6030

0.0287

0.4939

23

006A28

7.2208

0.7445

0.0255

0.4959

24

007A18

7.3754

0.6930

0.0263

0.4957

25

007A22

7.4312

0.7336

0.0282

0.4980

26

007A23

7.3408

0.7335

0.0282

0.4975

27

007A26

7.4954

0.6710

0.0268

0.4939

28

008A17

7.5512

0.6786

0.0258

0.4977

29

008A29

7.3158

0.7448

0.0272

0.4969

30

008A30

7.4704

0.6330

0.0264

0.4987

Table 3: Feature set values of d-hv-lbp glcm for middle age images.

S. no

Image Name

Contrast

Corre lation

Energy

Homo geneity

1

001A43a

7.6185

0.6472

0.0281

0.4970

2

002A31

7.5360

0.6681

0.0266

0.4951

3

002A38

7.5829

0.6728

0.0288

0.4927

4

003A35

7.6185

0.6693

0.0294

0.4981

5

003A47

7.4068

0.7221

0.0287

0.5023

6

003A49

7.5360

0.7611

0.0291

0.4996

7

001A43b

7.5310

0.7399

0.0276

0.5026

8

001A33

7.5829

0.6451

0.0283

0.4879

9

001A40

7.4068

0.7221

0.0257

0.4959

10

003A47

7.6185

0.6513

0.0272

0.4926

11

002A36

7.4568

0.6735

0.0292

0.4986

12

003A38

7.6185

0.6951

0.0278

0.5019

13

004A37

7.4068

0.7228

0.0313

0.4909

14

004A40

7.5329

0.6728

0.0293

0.5007

15

004A48

7.5360

0.7221

0.0271

0.4992

16

006A31

7.3568

0.7388

0.0267

0.4939

17

006A36

7.5360

0.6451

0.0277

0.5016

18

006A40

7.5360

0.6679

0.0303

0.4976

19

006A42

7.5860

0.6728

0.0282

0.4921

20

006A44

7.4068

0.6673

0.0282

0.5009

21

006A46

7.4318

0.7721

0.0272

0.4956

22

006A48

7.5829

0.6690

0.0277

0.4988

23

006A50

7.5829

0.7444

0.0267

0.4969

24

008A41

7.6079

0.6951

0.0262

0.4971

25

008A43

7.6685

0.7013

0.0286

0.5011

26

008A45

7.6435

0.6629

0.0301

0.4929

27

008A47

7.5685

0.6895

0.0268

0.4946

28

011A34

7.4860

0.6513

0.0302

0.4974

29

011A40

7.5610

0.6906

0.0282

0.4989

30

011A42

7.6329

0.6618

0.0252

0.5049

Table 4: Feature set values of d-hv-lbp-glcm for senior age images

S. no

Image Name

Contrast

Correlati on

Energy

Homo geneity

1

003A51

8.4213

0.6165

0.0262

0.4722

2

003A53

8.4213

0.6381

0.0278

0.4676

3

003A58

8.3158

0.6024

0.0255

0.4909

4

003A60

8.3658

0.6346

0.0271

0.4763

5

003A61

8.3543

0.6065

0.0267

0.4812

6

004A51

7.9646

0.6074

0.0233

0.4743

7

004A53

7.9212

0.5974

0.0261

0.4802

8

004A55

8.1146

0.6362

0.0271

0.4716

9

004A57

8.3713

0.6008

0.0268

0.4772

10

004A62

8.5488

0.6412

0.0269

0.4792

11

006A55

7.9146

0.6918

0.0228

0.4900

12

003A60

7.8212

0.6331

0.0261

0.4899

13

004A63

8.3213

0.6122

0.0250

0.4702

14

006A61

8.2658

0.6015

0.0272

0.4696

15

006A69

8.4488

0.5924

0.0261

0.4763

16

003A57

8.2043

0.6431

0.0268

0.4879

17

004A55

7.9212

0.6262

0.0254

0.4682

18

004A57

8.1543

0.6312

0.0238

0.4696

19

004A59

8.0146

0.7002

0.0257

0.4702

20

004A61

8.0212

0.6222

0.0260

0.4706

21

004A63

8.3658

0.6415

0.0256

0.4783

22

004A65

8.4988

0.7068

0.0277

0.4910

23

004A67

8.5213

0.6172

0.0264

0.4880

24

004A69

8.5488

0.6205

0.0266

0.4773

25

006A51

8.2543

0.7018

0.0236

0.4899

26

006A54

8.4658

0.6272

0.0279

0.4919

27

006A57

8.0146

0.6481

0.0234

0.4900

28

006A60

7.8712

0.6115

0.0259

0.4712

29

006A63

8.2543

0.6968

0.0282

0.4920

30

006A66

8.6488

0.6099

0.0266

0.4792

  • IV.    Comparison of the proposed method with other

EXISTING METHODS

The proposed D-HV-LBP-GLCM method is compared with other existing methods like Identification of facial parts and RBF Neural Network Classifier proposed by M. Yazdi et.al [15] and two geometric features and three wrinkle features from a facial image proposed by Wen-Bing Horng [16]. The classification rates are listed in table 6. The graphical representation of this is shown in Fig.4.

Table 5: Test vector feature set values of d-hv-lbp-glcm for different dataset images.

Sno

Image Name

Contrast

Correlation

Energy

Homo geneity

Group

Result

1

gogle_im_01

7.6068

0.7334

0.0333

0.5109

Middle

Success

2

gogle_im_02

7.1457

0.7356

0.0267

0.4735

Child

Success

3

gogle_im_03

7.5497

0.7290

0.0264

0.4955

Young

Success

4

gogle_im_04

7.1462

0.7211

0.0264

0.4786

Child

Success

5

gogle_im_05

6.6068

0.6334

0.0223

0.4511

Middle

Fail

6

gogle_im_06

8.0669

0.6293

0.0244

0.4691

Senior

Success

7

gogle_im_07

7.5694

0.6674

0.0285

0.4946

Middle

Success

8

gogle_im_08

8.0377

0.6287

0.0246

0.4689

Senior

Success

9

gogle_im_09

7.5610

0.7238

0.0267

0.4954

Young

Success

10

gogle_im_10

7.5384

0.7342

0.0261

0.4956

Young

Success

11

076A14

7.1283

0.7557

0.0263

0.4749

Child

Success

12

077A00

7.1213

0.6691

0.0269

0.4914

Child

Success

13

082A20

7.4731

0.7625

0.0271

0.4963

Young

Success

14

082A25

7.5118

0.7590

0.0266

0.4961

Young

Success

15

067A33

7.5569

0.6662

0.0290

0.4960

Middle

Success

16

067A39

7.5610

0.6704

0.0293

0.4948

Middle

Success

17

048A52

6.5527

0.5520

0.0287

0.4971

Middle

Fail

18

048A54

8.2935

0.6068

0.0261

0.4699

Senior

Success

19

067A48

7.5548

0.6641

0.0289

0.4965

Middle

Success

20

048A65

7.0605

0.6912

0.0271

0.4953

Child

Success

21

sca.img-001

7.1248

0.7124

0.0266

0.4832

Child

Success

22

sca.img-002

7.4924

0.7608

0.0269

0.4962

Young

Success

23

sca.img-003

8.2797

0.6042

0.0266

0.4698

Senior

Success

24

sca.img-004

7.7123

0.6911

0.0257

0.4978

Young

Success

25

sca.img-005

6.2960

0.7141

0.0276

0.4835

Senior

Fail

26

sca.img-006

8.2866

0.6055

0.0263

0.4699

Senior

Success

27

sca.img-007

7.5073

0.7206

0.0275

0.4972

Middle

Success

28

sca.img-008

7.5451

0.6948

0.0276

0.4980

Middle

Success

29

sca.img-009

7.6983

0.7042

0.0255

0.4967

Young

Success

30

sca.img-010

7.1031

0.7134

0.0269

0.4844

Child

Success

Table 6: Classification rate of the proposed d-hv-lbp-glcm method with other existing methods

Image Dataset

Identificatio n of facial parts and RBF

Neural

Network

Geometric and wrinkle features

Prposed D-HV-LBP-GLCM Method

G-NET

89.67

90.52

93.23

Google

85.3

81.58

92.5

Scanned

88.72

85.42

91.5

Average

87.9

85.84

92.41

  • ■    Identification of facial parts and RBF Neural Network

  • ■    Geometric and wrinkle features

■ Prposed D-HV-LBP-GLCM Method

Fig 4: Classification chart of proposed method and other existing methods.

  • V.    Conclusion

    The proposed DL-LBP-GLCM reduced the computational time complexity because of the reduced size of the DL-LBP from 6561 to 14 as in the case of original LBP and 2020 to 14 as in the case of Fuzzy LBP. This new method combines the merits of both GLCM and DL-LBP for the effective age classification purpose.

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