Smart Tracking for Edge-assisted Object Detection : Deep Reinforcement Learning for Multi-objective Optimization of Tracking-based Detection Process

Abstract: Detecting generic objects is one important sensing task for applications that need to understand the environment, for example eXtended Reality (XR), drone navigation etc. However, Object Detection algorithms are particularly computationally heavy for real-time video analysis on resource-constrained mobile devices. Thus Object Tracking, which is a much lighter process, is introduced under the Tracking-By-Detection (TBD) paradigm to alleviate the computational overhead. Still, it is common that the configurations of the TBD remain unchanged, which would result in unnecessary computation and/or performance loss in many cases.\\ This Master's Thesis presents a novel approach for multi-objective optimization of the TBD process on precision and latency, with the platform being power-constrained devices. We propose a Deep Reinforcement Learning based scheduling architecture that selects appropriate TBD actions in video sequences to achieve the desired goals. Specifically, we develop a simulation environment providing Markovian state information as input for the scheduler neural network, justified options of TBD actions, and a scalarized reward function to combine the multiple objectives. Our results demonstrate that the trained policies can learn to utilize content information from the current and previous frames, thus optimally controlling the TBD process at each frame. The proposed approach outperforms the baselines that have fixed TBD configurations and recent research works, achieving the precision close to pure detection while keeping the latency much lower. Both tuneable configurations show positive and synergistic contribution to the optimization objectives. We also show that our policies are generalizable, with inference and action time of the scheduler having minimal latency overhead. This makes our scheduling design highly practical in real XR or similar applications on power-constrained devices.