Multi-view Face Detection Research Articles

A view-based statistical system for multi-view face detection and pose estimation

This study develops a novel statistical system for automatic multi-view face detection and pose estimation. The five-module detection system is based on significant local facial features (or subregions) rather than the entire face. The low- and high-frequency feature information of each subregion of the facial image are extracted and projected onto the eigenspace and residual independent basis space in order to create the corresponding PCA (principal component analysis) projection weight vector and ICA (independent component analysis) coefficient vector, respectively. Therefore, the proposed system has an improved tolerance toward different facial expressions, wide viewing angles, partial occlusions and lighting conditions. Furthermore, either projection weight vectors or coefficient vectors in the PCA or ICA space have divergent distributions and are therefore modeled by using the weighted Gaussian mixture model (GMM) rather than a single Gaussian model. The GMM weights and parameters of the GMM are estimated iteratively using the Expectation-Maximization (EM) algorithm. Face detection is then performed by conducting a likelihood evaluation process based on the estimated joint probability of the weight and coefficient vectors and the corresponding geometric positions of the subregions. The use of subregion position information can reduce the risk of false acceptances. Moreover, simple cascaded rejecter module is employed to exclude 85% of the non-face images in order to enhance the overall system performance. The computational overhead is further reduced by eliminating the requirement for a residual image reconstruction process in the ICA process. Finally, the performance of the proposed system is evaluated using challenging databases. The results not only demonstrate the ability of the system to automatically identify facial images with a high degree of accuracy, but also verify its ability to estimate the fine pose angles with 5° precision and an over 90% accuracy rate.

High-Performance Rotation Invariant Multiview Face Detection

Rotation invariant multiview face detection (MVFD) aims to detect faces with arbitrary rotation-in-plane (RIP) and rotation-off-plane (ROP) angles in still images or video sequences. MVFD is crucial as the first step in automatic face processing for general applications since face images are seldom upright and frontal unless they are taken cooperatively. In this paper, we propose a series of innovative methods to construct a high-performance rotation invariant multiview face detector, including the Width-First-Search (WFS) tree detector structure, the Vector Boosting algorithm for learning vector-output strong classifiers, the domain-partition-based weak learning method, the sparse feature in granular space, and the heuristic search for sparse feature selection. As a result of that, our multiview face detector achieves low computational complexity, broad detection scope, and high detection accuracy on both standard testing sets and real-life images.

Multi-view face and eye detection using discriminant features

Multi-view face detection plays an important role in many applications. This paper presents a statistical learning method to extract features and construct classifiers for multi-view face detection. Specifically, a recursive nonparametric discriminant analysis (RNDA) method is presented. The RNDA relaxes Gaussian assumptions of Fisher discriminant analysis (FDA), and it can handle more general class distributions. RNDA also improves the traditional nonparametric discriminant analysis (NDA) by alleviating its computational complexity. The resulting RNDA features provide better accuracy than the commonly used Haar features in detecting objects of complex shapes. Histograms of extracted features are learned to represent class distributions and to construct probabilistic classifiers. RNDA features are subsequently learned and combined with AdaBoost to form a multi-view face detector. The method is applied to both multi-view face and eye detection, and experimental results demonstrate improved performance over existing methods.

Real-Time Multi-View Face Detection and Pose Estimation Based on Cost-Sensitive AdaBoost

Locating multi-view faces in images with a complex background remains a challenging problem. In this paper, an integrated method for real-time multi-view face detection and pose estimation is presented. A simple-to-complex and coarse-to-fine view-based detector architecture has been designed to detect multi-view faces and estimate their poses efficiently. Both the pose estimators and the view-based face/nonface detectors are trained by a cost-sensitive AdaBoost algorithm to improve the generalization ability. Experimental results show that the proposed multi-view face detector, which can be constructed easily, gives more robust face detection and pose estimation and has a faster real-time detection speed compared with other conventional methods.

A Multi-View Face Detection Based on Real Adaboost Algorithm

A Multi-View Face Detection Based on Real Adaboost Algorithm

FLD를 이용한 얼굴 검출 알고리즘의 성능 향상

영상에서 얼굴이 있는 위치를 찾거나 얼굴을 검출하기 위한 많은 방법들이 연구되고 있다. 영상에서 얼굴 검출은 얼굴의 크기, 얼굴이 있는 위치, 그리고 다양한 포즈, 조명 상태 등의 변화에 따라 달라진다 따라서 얼굴 검출과 인식에 있어서의 어려운 점은 얼굴의 크기와 위치, 거리, 조명, 포즈 때문에 나타나는 것이다. 본 논문에서는 다양한 얼굴 크기와 얼굴이 있는 위치 등에 강인한 얼굴 검출을 위해 피셔의 선형 판별 함수를 이용하는 방법을 제안한다. 선형 판별식을 이용하여 효과적으로 얼굴을 검출하기 위해서는 학습 방법 및 학습에 사용되는 데이터들의 구성이 중요하다. 그 이유는, 얼굴 검출을 위해 사용되는 학습 데이터들은 조명과 포즈에 영향을 받기 때문에 얼굴의 특징들을 반영하는 학습 데이터들의 구성이 중요하다. 따라서 본 논문에서는 복잡한 배경과 다양한 크기의 얼굴을 검출하기 위한 계층적인 방법을 제시하며, 효과적인 피셔 판별 분석을 위하여 얼굴과 비얼굴 학습 데이터의 효율적인 분류 방법을 제안한다. Many reported methods assume that the faces in an image or an image sequence have been identified and localization. Face detection from image is a challenging task because of the variability in scale, location, orientation and pose. The difficulties in visual detection and recognition are caused by the variations in viewpoint, viewing distance, illumination. In this paper, we present an efficient linear discriminant for multi-view face detection and face location. We define the training data by using the Fisher`s linear discriminant in an efficient learning method. Face detection is very difficult because it is influenced by the poses of the human face and changes in illumination. This idea can solve the multi-view and scale face detection problems. In this paper, we extract the face using the Fisher`s linear discriminant that has hierarchical models invariant size and background. The purpose of this paper is to classify face and non-face for efficient Fisher`s linear discriminant.

FloatBoost learning and statistical face detection

A novel learning procedure, called FloatBoost, is proposed for learning a boosted classifier for achieving the minimum error rate. FloatBoost learning uses a backtrack mechanism after each iteration of AdaBoost learning to minimize the error rate directly, rather than minimizing an exponential function of the margin as in the traditional AdaBoost algorithms. A second contribution of the paper is a novel statistical model for learning best weak classifiers using a stagewise approximation of the posterior probability. These novel techniques lead to a classifier which requires fewer weak classifiers than AdaBoost yet achieves lower error rates in both training and testing, as demonstrated by extensive experiments. Applied to face detection, the FloatBoost learning method, together with a proposed detector pyramid architecture, leads to the first real-time multiview face detection system reported.

Support vector machine based multi-view face detection and recognition

Detecting faces across multiple views is more challenging than in a fixed view, e.g. frontal view, owing to the significant non-linear variation caused by rotation in depth, self-occlusion and self-shadowing. To address this problem, a novel approach is presented in this paper. The view sphere is separated into several small segments. On each segment, a face detector is constructed. We explicitly estimate the pose of an image regardless of whether or not it is a face. A pose estimator is constructed using Support Vector Regression. The pose information is used to choose the appropriate face detector to determine if it is a face. With this pose-estimation based method, considerable computational efficiency is achieved. Meanwhile, the detection accuracy is also improved since each detector is constructed on a small range of views. We developed a novel algorithm for face detection by combining the Eigenface and SVM methods which performs almost as fast as the Eigenface method but with a significant improved speed. Detailed experimental results are presented in this paper including tuning the parameters of the pose estimators and face detectors, performance evaluation, and applications to video based face detection and frontal-view face recognition.

Composite support vector machines for detection of faces across views and pose estimation

Abstract Support vector machines (SVMs) have shown great potential for learning classification functions that can be applied to object recognition. In this work, we extend SVMs to model the appearance of human faces which undergo non-linear change across multiple views. The approach uses inherent factors in the nature of the input images and the SVM classification algorithm to perform both multi-view face detection and pose estimation.