Geometry-based Adaptive Symbolic Approximation for Fast Sequence Matching on Manifolds
This addresses the need for efficient real-time processing in domains like human activity analysis, though it appears incremental as it generalizes existing symbolic methods to non-Euclidean settings.
The paper tackled the problem of fast indexing for sequences in non-Euclidean spaces, such as human activity analysis, by proposing a geometry-based adaptive symbolic approximation framework that reduces expensive geodesic computations with minimal accuracy loss, achieving high speed and accuracy in applications like activity recognition.
In this paper, we consider the problem of fast and efficient indexing techniques for sequences evolving in non-Euclidean spaces. This problem has several applications in the areas of human activity analysis, where there is a need to perform fast search, and recognition in very high dimensional spaces. The problem is made more challenging when representations such as landmarks, contours, and human skeletons etc. are naturally studied in a non-Euclidean setting where even simple operations are much more computationally intensive than their Euclidean counterparts. We propose a geometry and data adaptive symbolic framework that is shown to enable the deployment of fast and accurate algorithms for activity recognition, dynamic texture recognition, motif discovery. Toward this end, we present generalizations of key concepts of piece-wise aggregation and symbolic approximation for the case of non-Euclidean manifolds. We show that one can replace expensive geodesic computations with much faster symbolic computations with little loss of accuracy in activity recognition and discovery applications. The framework is general enough to work across both Euclidean and non-Euclidean spaces, depending on appropriate feature representations without compromising on the ultra-low bandwidth, high speed and high accuracy. The proposed methods are ideally suited for real-time systems and low complexity scenarios.