Feature level analysis for 3D facial expression recognition

3D facial expression recognition has great potential in human computer interaction and intelligent robot systems. In this paper, we propose a two-step approach which combines both the feature selection and the feature fusion techniques to choose more comprehensive and discriminative features for 3D facial expression recognition. In the feature selection stage, we utilize a novel normalized cut-based filter (NCBF) algorithm to select the high relevant and low redundant geometrically localized features (GLF) and surface curvature features (SCF), respectively. Then in the feature fusion stage, PCA is performed on the selected GLF and SCF in order to avoid the curse-of-dimensionality challenge. Finally, the processed GLF and SCF are fused together to capture the most discriminative information in 3D expressional faces. Experiments are carried out on the BU-3DFE database, and the proposed approach outperforms the conventional methods by providing more competitive results.