Improved Spatio-temporal Salient Feature Detection for Action Recognition
Amir-Hossein Shabani, David A. Clausi, John Zelek · 2011
Spatio-temporal salient features can localize the local motion events and are used to represent video sequences for many computer vision tasks such as action recognition. The robust detection of these features under geometric variations such as affine transformation and view/scale changes is however an open problem. Existing methods use the same filter for both time and space and hence, perform an isotropic temporal filtering. A novel anisotropic temporal filter for better spatio-temporal feature detection is developed. The effect of symmetry and causality of the video filtering is investigated. Based on the positive results of precision and reproducibility tests, we propose the use of temporally asymmetric filtering for robust motion feature detection and action recognition.