LDA-CNN: Linear Discriminant Analysis Convolution Neural Network for Periocular Recognition in the Wild

Due to the COVID-19 pandemic, the necessity for a contactless biometric system able to recognize masked faces drew attention to the periocular region as a valuable biometric trait. However, periocular recognition remains challenging for deployments in the wild or in unconstrained environments where...

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Main Authors: Amani Alahmadi, Muhammad Hussain, Hatim Aboalsamh
Format: Article
Language:English
Published: MDPI AG 2022-12-01
Series:Mathematics
Subjects:
Online Access:https://www.mdpi.com/2227-7390/10/23/4604
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author Amani Alahmadi
Muhammad Hussain
Hatim Aboalsamh
author_facet Amani Alahmadi
Muhammad Hussain
Hatim Aboalsamh
author_sort Amani Alahmadi
collection DOAJ
description Due to the COVID-19 pandemic, the necessity for a contactless biometric system able to recognize masked faces drew attention to the periocular region as a valuable biometric trait. However, periocular recognition remains challenging for deployments in the wild or in unconstrained environments where images are captured under non-ideal conditions with large variations in illumination, occlusion, pose, and resolution. These variations increase within-class variability and between-class similarity, which degrades the discriminative power of the features extracted from the periocular trait. Despite the remarkable success of convolutional neural network (CNN) training, CNN requires a huge volume of data, which is not available for periocular recognition. In addition, the focus is on reducing the loss between the actual class and the predicted class but not on learning the discriminative features. To address these problems, in this paper we used a pre-trained CNN model as a backbone and introduced an effective deep CNN periocular recognition model, called linear discriminant analysis CNN (LDA-CNN), where an LDA layer was incorporated after the last convolution layer of the backbone model. The LDA layer enforced the model to learn features so that the within-class variation was small, and the between-class separation was large. Finally, a new fully connected (FC) layer with softmax activation was added after the LDA layer, and it was fine-tuned in an end-to-end manner. Our proposed model was extensively evaluated using the following four benchmark unconstrained periocular datasets: UFPR, UBIRIS.v2, VISOB, and UBIPr. The experimental results indicated that LDA-CNN outperformed the state-of-the-art methods for periocular recognition in unconstrained environments. To interpret the performance, we visualized the discriminative power of the features extracted from different layers of the LDA-CNN model using the t-distributed Stochastic Neighboring Embedding (t-SNE) visualization technique. Moreover, we conducted cross-condition experiments (cross-light, cross-sensor, cross-eye, cross-pose, and cross-database) that proved the ability of the proposed model to generalize well to different unconstrained conditions.
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spelling doaj.art-709f28b044234d33b46edf3634095d652023-11-24T11:36:29ZengMDPI AGMathematics2227-73902022-12-011023460410.3390/math10234604LDA-CNN: Linear Discriminant Analysis Convolution Neural Network for Periocular Recognition in the WildAmani Alahmadi0Muhammad Hussain1Hatim Aboalsamh2Department of Computer Science, College of Computer and Information Sciences, King Saud University, Riyadh 11543, Saudi ArabiaDepartment of Computer Science, College of Computer and Information Sciences, King Saud University, Riyadh 11543, Saudi ArabiaDepartment of Computer Science, College of Computer and Information Sciences, King Saud University, Riyadh 11543, Saudi ArabiaDue to the COVID-19 pandemic, the necessity for a contactless biometric system able to recognize masked faces drew attention to the periocular region as a valuable biometric trait. However, periocular recognition remains challenging for deployments in the wild or in unconstrained environments where images are captured under non-ideal conditions with large variations in illumination, occlusion, pose, and resolution. These variations increase within-class variability and between-class similarity, which degrades the discriminative power of the features extracted from the periocular trait. Despite the remarkable success of convolutional neural network (CNN) training, CNN requires a huge volume of data, which is not available for periocular recognition. In addition, the focus is on reducing the loss between the actual class and the predicted class but not on learning the discriminative features. To address these problems, in this paper we used a pre-trained CNN model as a backbone and introduced an effective deep CNN periocular recognition model, called linear discriminant analysis CNN (LDA-CNN), where an LDA layer was incorporated after the last convolution layer of the backbone model. The LDA layer enforced the model to learn features so that the within-class variation was small, and the between-class separation was large. Finally, a new fully connected (FC) layer with softmax activation was added after the LDA layer, and it was fine-tuned in an end-to-end manner. Our proposed model was extensively evaluated using the following four benchmark unconstrained periocular datasets: UFPR, UBIRIS.v2, VISOB, and UBIPr. The experimental results indicated that LDA-CNN outperformed the state-of-the-art methods for periocular recognition in unconstrained environments. To interpret the performance, we visualized the discriminative power of the features extracted from different layers of the LDA-CNN model using the t-distributed Stochastic Neighboring Embedding (t-SNE) visualization technique. Moreover, we conducted cross-condition experiments (cross-light, cross-sensor, cross-eye, cross-pose, and cross-database) that proved the ability of the proposed model to generalize well to different unconstrained conditions.https://www.mdpi.com/2227-7390/10/23/4604periocular biometricmobile biometricsdeep learningconvolutional neural networktransfer learningfine-tuning
spellingShingle Amani Alahmadi
Muhammad Hussain
Hatim Aboalsamh
LDA-CNN: Linear Discriminant Analysis Convolution Neural Network for Periocular Recognition in the Wild
Mathematics
periocular biometric
mobile biometrics
deep learning
convolutional neural network
transfer learning
fine-tuning
title LDA-CNN: Linear Discriminant Analysis Convolution Neural Network for Periocular Recognition in the Wild
title_full LDA-CNN: Linear Discriminant Analysis Convolution Neural Network for Periocular Recognition in the Wild
title_fullStr LDA-CNN: Linear Discriminant Analysis Convolution Neural Network for Periocular Recognition in the Wild
title_full_unstemmed LDA-CNN: Linear Discriminant Analysis Convolution Neural Network for Periocular Recognition in the Wild
title_short LDA-CNN: Linear Discriminant Analysis Convolution Neural Network for Periocular Recognition in the Wild
title_sort lda cnn linear discriminant analysis convolution neural network for periocular recognition in the wild
topic periocular biometric
mobile biometrics
deep learning
convolutional neural network
transfer learning
fine-tuning
url https://www.mdpi.com/2227-7390/10/23/4604
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AT muhammadhussain ldacnnlineardiscriminantanalysisconvolutionneuralnetworkforperiocularrecognitioninthewild
AT hatimaboalsamh ldacnnlineardiscriminantanalysisconvolutionneuralnetworkforperiocularrecognitioninthewild