Authors: Chunhua Du, Jie Yang, Qiang Wu, Xiangjian He
Addresses: Institute of Image Processing and Pattern Recognition, Shanghai Jiao Tong University, Shanghai 200240, China. ' Institute of Image Processing and Pattern Recognition, Shanghai Jiao Tong University, Shanghai 200240, China. ' School of Computing and Communications, University of Technology, Sydney, P.O. Box 123, Broadway 2007, Australia. ' School of Computing and Communications, University of Technology, Sydney, P.O. Box 123, Broadway 2007, Australia
Abstract: Active shape model (ASM) plays an important role in face research such as face recognition, pose estimation and gaze estimation. A crucial step of the common ASM is finding a new position for each facial landmark at each iteration. Mahalanobis distance minimisation is used for this finding, provided there are enough training data such that the grey-level profiles for each landmark following a multivariate Gaussian distribution. However, this condition could not be satisfied in most cases. In this paper, a novel method support vector machine-based active shape model (SVMBASM) is proposed for this task. It approaches the finding task as a small sample size classification problem. Moreover, considering the poor classification performance caused by the imbalanced dataset which contains more negative instances (incorrect candidates for new position) than positive instances (correct candidates for new position), a multi-class classification framework is further proposed. Performance evaluation on Shanghai Jiao Tong University face database shows that the proposed SVMBASM outperforms the original ASM in terms of the average error and average frequency of convergence.
Keywords: active shape models; SVM; support vector machines; facial landmarks; multi-class classification; face recognition; pose estimation; gaze estimation
International Journal of Intelligent Systems Technologies and Applications, 2011 Vol.10 No.2, pp.151 - 170
Published online: 11 Mar 2011 *Full-text access for editors Access for subscribers Purchase this article Comment on this article