Open Access
Optimization of RBF-SVM hyperparameters using genetic algorithm for face recognit
Author(s) -
Yusuf Ibrahim,
Emmanuel Okafor,
B. Z. Yahaya
Publication year - 2021
Publication title -
nigerian journal of technology
Language(s) - English
Resource type - Journals
eISSN - 2467-8821
pISSN - 0331-8443
DOI - 10.4314/njt.v39i4.27
Subject(s) - hyperparameter , support vector machine , computer science , artificial intelligence , hyperparameter optimization , pattern recognition (psychology) , machine learning , genetic algorithm , face (sociological concept) , binary classification , facial recognition system , radial basis function , artificial neural network , social science , sociology
Manual grid-search tuning of machine learning hyperparameters is very time-consuming. Hence, to curb this problem, we propose the use of a genetic algorithm (GA) for the selection of optimal radial-basis-function based support vector machine (RBF-SVM) hyperparameters; regularization parameter C and cost-factor γ. The resulting optimal parameters were used during the training of face recognition models. To train the models, we independently extracted features from the ORL face image dataset using local binary patterns (handcrafted) and deep learning architectures (pretrained variants of VGGNet). The resulting features were passed as input to either linear-SVM or optimized RBF-SVM. The results show that the models from optimized RBFSVM combined with deep learning or hand-crafted features yielded performances that surpass models obtained from Linear-SVM combined with the aforementioned features in most of the data splits. The study demonstrated that it is profitable to optimize the hyperparameters of an SVM to obtain the best classification performance.
Keywords: Face Recognition, Feature Extraction, Local Binary Patterns, Transfer Learning, Genetic Algorithm and Support Vector Machines.