Discriminant appearance weighting for action recognition

Extending popular histogram representations of local motion patterns, we present a novel weighted integration method based on an assumption that a motion importance should be changed by its appearance to obtain better recognition accuracies. The proposed integration method of motion and appearance patterns can weight information involving "what is moving" by discriminant way. The discriminant weights can be learned efficiently and naturally using two-dimensional fisher discriminant analysis (or, fisher weight maps) of co-occurrence matrices. Original fisher weight maps lose shift invariance of histogram features, while the proposed method preserves it. Experimental results on KTH human action dataset and UT-interaction dataset revealed the effectiveness of the proposed integration compared to naive integration methods of independent motion and appearance features and also other state-of-the-art methods.