Weighted-fusion feature of MB-LBPUH and HOG for facial expression recognition

Obtaining a useful and discriminative feature for facial expression recognition (FER) is a hot research topic in computer vision. In this paper, we propose a novel facial expression representation for FER. Firstly, we select the appropriate parameter of multi-scale block local binary pattern uniform histogram (MB-LBPUH) operator to filter the facial images for representing the holistic structural features. Then, normalizing the filtered images into a uniform basis reduces the computational complexity and remains the full information. An MB-LBPUH feature and a HOG feature are concatenated to fuse a new feature representation for characterizing facial expressions. At the same time, weighting the MB-LBPUH feature can remove the data unbalance from a fusion feature. The weighted-fusion feature reflects not only global facial expressions structure patterns but also characterizes local expression texture appearance and shape. Finally, we utilize principal component analysis for dimensionality reduction and employ support vector machine to classification. Experimental results demonstrate that the proposed algorithm exhibits superior performance compared with the existing algorithms on JAFFE, CK+, and BU-3DFE datasets.