Online Semantic Activity Forecasting with DARKO

We address the problem of continuously observing and forecasting long-term semantic activities of a first-person camera wearer: what the person will do, where they will go, and what goal they are seeking. In contrast to prior work in trajectory forecasting and short-term activity forecasting, our algorithm, DARKO, reasons about the future position, future semantic state, and future high-level goals of the camera-wearer at arbitrary spatial and temporal horizons defined only by the wearer’s behaviors. DARKO learns and forecasts online from first-person observations of the user’s daily behaviors. We derive novel mathematical results that enable efficient forecasting of different semantic quantities of interest. We apply our method to a dataset of 5 largescale environments with 3 different environment types, collected from 3 different users, and experimentally validate DARKO on forecasting tasks.