A unified formalism for video descriptors

In this paper, we propose a unified formalism for video descriptors. This formalism is based on the descriptors decomposition in three levels: primitive, scattering and projection. With this framework, we are able to rewrite easily all the usual descriptors in the literature such as HOG, HOF, SURF. Then, we propose a new projection method based on approximation with a finite expansion of orthogonal polynomials. Using our framework, we extend all usual descriptors by switching the projection step. The experiments are carried out on the well known KTH dataset and on the more challenging Hollywood 2 action classification dataset and show state of the art results.