Learning representative local features for face detection

This paper describes a face detection approach via learning local features. The key idea is that local features, being manifested by a collection of pixels in a local region, are learnt from the training set instead of arbitrarily defined. The learning procedure consists of two steps. First, a modified version of NMF (non-negative matrix factorization), namely local NMF (LNMF), is applied to obtain an overcomplete set of local features. Second, a learning algorithm based on AdaBoost is used to select a small number of local features and yields extremely efficient classifiers. Experiments are presented which show that face detection performance is comparable to state-of-the-art face detection systems.