Face Recognition Method Based on Adaptively Weighted Block-Two Dimensional Principal Component Analysis

One of the widely used approaches in image recognition is principal component analysis (PCA) because of the good balance between the simplicity and speed of the algorithm and the results obtained by using it. In the last years many variants of PCA were developed: two dimensional PCA, two directional two dimensional PCA, extended two dimensional PCA and extended two dimensional two directional PCA, the last one developed by the first two authors of the present paper. In this paper we go further with this study by considering a mixed approach between E2DPCA and diagonal PCA. The mixed approach not only takes approximately the same amount of time for training and testing as the classical approach, but also gives better recognition accuracy for some of the PCA algorithm variants.

The literature on independent component analysis (ICA)-based face recognition generally evaluates its performance using standard principal component analysis (PCA) within two architectures, ICA Architecture I and ICA Architecture II. In this correspondence, we analyze these two ICA architectures and find that ICA Architecture I involves a vertically centered PCA process (PCA I), while ICA Architecture II involves a whitened horizontally centered PCA process (PCA II). Thus, it makes sense to use these two PCA versions as baselines to reevaluate the performance of ICA-based face-recognition systems. Experiments on the FERET, AR, and AT&T face-image databases showed no significant differences between ICA Architecture I (II) and PCA I (II), although ICA Architecture I (or II) may, in some cases, significantly outperform standard PCA. It can be concluded that the performance of ICA strongly depends on the PCA process that it involves. Pure ICA projection has only a trivial effect on performance in face recognition.

Aerosol optical parameters detected by multiwavelength lidar can be used for the retrieval of the aerosol particle size distribution and aerosol microphysical properties (AMP). Based on the retrieval for AMPs using standard principal component analysis (PCA) algorithm, the influence of the number of optical parameters on the PCA retrieval results is studied. Four optical parameters (3β + α) or three optical parameters (3β) are selected for retrieval instead of five optical parameters (3β + 2α), respectively. The results show that three optical parameters and four optical parameters can be used for the retrieval of AMPs. For 3β + α, the accuracy of effective radius and volume concentration (VC) are 37% and 56%, respectively. For 3β, the accuracy of effective radius and VC are 37% and 74% respectively. The sensitivity analysis of the PCA algorithm with less than five optical parameters is also discussed, and this method is applied to the retrieval of cloud base particle size distribution.

In this paper, we propose Two-Dimensional Robust Face Recognition System Realized with the Aid of Facial Symmetry with Illumination Variation. Preprocessing process is carried out to obtain mirror image which means new image rearranged by using difference between light and shade of right and left face based on a vertical axis of original face image. After image preprocessing, high dimensional image data is transformed to low-dimensional feature data through 2-directional and 2-dimensional Principal Component Analysis (2D)2PCA, which is one of dimensional reduction techniques. Polynomial-based Radial Basis Function Neural Network pattern classifier is used for face recognition. While FCM clustering is applied in the hidden layer, connection weights are defined as a linear polynomial function. In addition, the coefficients of linear function are learned through Weighted Least Square Estimation(WLSE). The Structural as well as parametric factors of the proposed classifier are optimized by using Particle Swarm Optimization(PSO). In the experiment, Yale B data is employed in order to confirm the advantage of the proposed methodology designed in the diverse illumination variation

Spatial domain facial recognition Modular IMage Principal Component Analysis (MIMPCA) has an improved recognition rate compared to the conventional PCA. In the MPCA, face images are divided into smaller sub-images and the PCA approach is applied to each of these sub-images. In this work, the Transform Domain implementation of MPCA is presented. The facial image has two representations. The Two Dimensional MPCA (TD - 2D - MPCA) and the Diagonal matrix MPCA (TD - Dia - MPCA). The sub-images are processed using both non-overlapping and overlapping windows. All the test results, for noise free and noisy images, using ORL, Yale and FERET databases achieved; 99.5%, 99.58% and 97.42% recognition accuracy respectively. Transform Domain implementations yield, computational and storage savings of at least 75% and 99.98%, respectively, compared to spatial domain. Sample results are given.

Face recognition is one technology that is commonly used now. Therefore, various algorithms continue to be developed to obtain maximum results with minimum costs. One of them is the Deep Neural Network or DNN algorithm. While DNN requires a large dataset to train the algorithm, another algorithm called the Principal Component Analysis (PCA) algorithm works good in a smaller dataset. These algorithms are compared to know which algorithm has the better result in given circumstances. Later the accuracy, speed, and optimality of the algorithms are analyzed. By comparing these algorithms, we could know which algorithm is preferable in given circumstances. After the experiment is done, we can assume that the two algorithms have a slight difference in terms of accuracy. Also, the time used for running the PCA implementation code is slightly longer than DNN. However, that does not mean that the PCA algorithm is not great. If the dataset to be used is limited, PCA is going to be a good choice.

Nonlinear principal component analysis (NLPCA) is known as a nonlinear generalization of the standard principal component analysis (PCA). Since nonlinear PCA is a non-unique concept, it is discussed, how nonlinear PCA can be defined as a nonlinear feature extraction technique most similar to linear PCA. The nonlinear reduction of a data set from its original dimension to the intrinsic dimension of the data is one aspect, but we also request that the nonlinear features spanning this intrinsic data space are hierarchically arranged similar to the linear features of PCA. Thus, such nonlinear PCA is a powerful pre-processing step. It can be used as nonlinear sphering (whitening) or it can be considered as a smoothing method which removes nonlinear correlations between variables. Nonlinear PCA can be performed by minimizing a hierarchical error function. This error function is applied to the autoencoder which is a multi-layer perceptron used in auto-associative mode to perform the identity mapping.

An efficient method of face detection based on two-dimensional principal component analysis (PCA) incorporating with support vector machine (SVM) is proposed in this paper. Firstly, a 2DPCA coarse filter with relatively lower computational complexity is applied to the whole input image to filter out most of the non-face, then follows the SVM classifier to make the final decision, so the detection process is speeded up. As opposed to PCA, 2DPCA is based on 2D image matrices rather than ID vector so the image matrix does not need to be transformed into a vector prior to feature extraction. The experiment results show that the method can effectively detect faces under complicated background, and the processing time is shorter than using SVM alone

In this paper, a novel approach for illumination normalization under varying lighting conditions is presented. Our approach utilizes the fact that discrete cosine transform (DCT) low-frequency coefficients correspond to illumination variations in a digital image. Under varying illuminations, the images captured may have low contrast; initially we apply histogram equalization on these for contrast stretching. Then the low-frequency DCT coefficients are scaled down to compensate the illumination variations. The value of scaling down factor and the number of low-frequency DCT coefficients, which are to be re-scaled, are obtained experimentally. The classification is done using k-nearest neighbor classification and nearest mean classification on the images obtained by inverse DCT on the processed coefficients. The correlation coefficient and Euclidean distance obtained using principal component analysis are used as distance metrics in classification. We have tested our face recognition method using Yale face database B. The results show that our method performs without any error (100% face recognition performance) even on the most extreme illumination variations. There are different schemes in the literature for illumination normalization under varying lighting conditions, but no one is claimed to give 100% recognition rate under all illumination variations for this database. The proposed technique is computationally efficient and can easily be implemented for real time face recognition system.

A new method of face recognition based on gradient direction histogram (HOG) features extraction and fast principal component analysis (PCA) algorithm is proposed to solve the problem of low accuracy of face recognition under non-restrictive conditions. In this method, the Haar feature classifier is used to extract and extract the original data, and then the HOG features are extracted from the image data and the PCA dimension reduction is processed, and the Support Vector Machines (SVM) algorithm is used to recognize the face. The experimental results of the classification recognition on the LFW face database verify the effectiveness of the method.

Feature extraction for machine learning-based intrusion detection in IoT networks

In standard Principal Component Analysis (PCA) comes one problem in addressing the set of incomplete data. The standard PCA procedure on incomplete data is to eliminate (listwise deletion procedure) or using the mean of the variable, this procedure may result in loss information from these observations. Another method used is to integrate Expectation Maximization (EM) to the method of Probabilistic Principal Component Analysis (PPCA). But PPCA can produce overfitting response prediction. In this study discussed the Variational Bayesian Principal Component Analysis (VBPCA) which is a method of development of PPCA method by incorporating prior information from the distribution of the principal components of the model parameters. From the simulation studies by eliminating the data through the concept of missing at random (MAR), obtained results that the value of the correlation scores principal components complete data with the principal component score predicted results PPCA method is superior when compared with VBPCA, as well as to the value of the correlation scores for the various percentages are generally incomplete data. However, judging from the size of a match between the response to predictions by the size normalized root mean square error of prediction (NRMSEP) VBPCA method produces better than PPCA.

Principal Component Analysis (PCA) is a well-studied method in face recognition. Noticing that few researches focus on pre-processing of images, which will also improve the performance of feature extraction of PCA algorithm, we present an improved approach of PCA based face recognition algorithm using Fast Fourier Transform (FFT). In our method, FFT is presented as a method to combine amplitude spectrum of one image with phase spectrum of another image as a mixed image. PCA is applied to do feature extraction and a kernel SVM is harnessed as a classifier. To test and evaluate the performance of the proposed approach, a series of experiments are performed on Yale face database A. The experimental results show that our proposed method is encouraging.

Face detection and recognition is very challenging due to the diverse variation of face appearance, facial expressions, variable recording conditions (changes in illumination, scale differences, varying face position...) and the complexity of image background. In this paper, we propose a new system which integrate color segmentation and two dimensional principal component analysis in the normalized RG space (2DPCA, to compress the red information as well as the green information) in order to detect faces and recognize facial features in color images that have not been preprocessed. We show some experimental results, using our own face database and the AR and PICS face databases. Then, we have compared results obtained with 2DPCA technique in the normalized RG space and other typical methods (2DPCA in the gray level space, PCA, Fisherfaces, Kernel PCA and Kernel Fisherfaces). Conclusions and future works have finally presented.

Comparison of five Lonicera flowers by simultaneous determination of multi-components with single reference standard method and principal component analysis