Facial expression recognition through modeling age-related spatial patterns

Abstract

In this paper we tackle the problem of expression recognition by exploiting age-related spatial facial expression patterns, which carry crucial information that have not been thoroughly exploited. First, we conduct two statistic hypothesis tests to investigate age effect on the spatial patterns of expressions and on facial expression recognition respectively. Second, we propose two methods to recognize expressions by modeling age-related spatial facial expression patterns. One is a three-node Bayesian Network to classify expressions with the help of age from person-independent geometric features. The other is to construct multiple Bayesian networks to explicitly capture the spatial facial expression patterns for different ages. For both methods, age information is used as privileged information, which is only available during training, and is exploited during training to construct a better classifier. Statistic analyses on two benchmark databases, i.e. the Lifespan and the FACES, verify the age effect on spatial patterns of expressions and on facial expression recognition. Experimental results of expression recognition demonstrate the effectiveness of the proposed methods in modelling age-related spatial patterns as well as their superior expression recognition performance to existing approaches.