Facial emotion recognition with anisotropic inhibited Gabor energy histograms
This paper presents a novel image descriptor called Derivative Variation Pattern (DVP) and its application to face and palmprint recognition. DVP captures image variations in both the frequency and the spatial domains. The effects of uncontrolled illumination are compensated in the frequency domain by discarding the illumination affected frequencies. Image pixels are encoded as binary patterns based on the higher-order spatial derivatives computed in the spatial domain. The proposed descriptor was evaluated on the Extended Yale-B and FERET face databases, and the PolyU palmprint database. Experimental results demonstrate the effectiveness of the DVP descriptor in both the face and the palmprint recognition tasks under uncontrolled illuminations. State-of-the-art approaches have yet to deliver a feature representation for facial emotion recognition that can be applied to non-trivial unconstrained, continuous video data sets. Initially, research advanced with the use of Gabor energy filters. However, in recent work more attention has been given to other features. Gabor energy filters lack generalization needed in unconstrained situations. Additionally, they result in an undesirably high feature vector dimensionality. Nontrivial data sets have millions of samples; feature vectors must be as low dimensional as possible. We propose a novel texture feature based on Gabor energy filters that offers generalization with a background texture suppression component and is as compact as possible due to a maximal response representation and local histograms. We improve performance on the non-trivial Audio/Visual Emotion Challenge 2012 grandchallenge data set.