Event detection and analysis from video streams

TLDR

We present a system that analyzes the behavior of moving objects in airborne video streams, detailing its design and evaluating it on real sequences. The system comprises two modules: a multi‑scale feature‑based detector and tracker that stabilizes the sequence and extracts residual‑motion regions, and a scenario‑instantiator that uses the resulting trajectories with geospatial and goal context. Experiments on real video sequences demonstrate the system’s effectiveness, with quantitative analysis confirming its performance.

Abstract

We present a system which takes as input a video stream obtained from an airborne moving platform and produces an analysis of the behavior of the moving objects in the scene. To achieve this functionality, our system relies on two modular blocks. The first one detects and tracks moving regions in the sequence. It uses a set of features at multiple scales to stabilize the image sequence, that is, to compensate for the motion of the observer, then extracts regions with residual motion and uses an attribute graph representation to infer their trajectories. The second module takes as input these trajectories, together with user-provided information in the form of geospatial context and goal context to instantiate likely scenarios. We present details of the system, together with results on a number of real video sequences and also provide a quantitative analysis of the results.