Video-Based Human Pose Regression via Decoupled Space-Time Aggregation
Authors: Jijie He, Wenwu Yang

By leveraging temporal dependency in video sequences multi-frame human pose estimation algorithms have demonstrated remarkable results in complicated situations such as occlusion motion blur and video defocus. These algorithms are predominantly based on heatmaps resulting in high computation and storage requirements per frame which limits their flexibility and real-time application in video scenarios particularly on edge devices. In this paper we develop an efficient and effective video-based human pose regression method which bypasses intermediate representations such as heatmaps and instead directly maps the input to the output joint coordinates. Despite the inherent spatial correlation among adjacent joints of the human pose the temporal trajectory of each individual joint exhibits relative independence. In light of this we propose a novel Decoupled Space-Time Aggregation network (DSTA) to separately capture the spatial contexts between adjacent joints and the temporal cues of each individual joint thereby avoiding the conflation of spatiotemporal dimensions. Concretely DSTA learns a dedicated feature token for each joint to facilitate the modeling of their spatiotemporal dependencies. With the proposed joint-wise local-awareness attention mechanism our method is capable of efficiently and flexibly utilizing the spatial dependency of adjacent joints and the temporal dependency of each joint itself. Extensive experiments demonstrate the superiority of our method. Compared to previous regression-based single-frame human pose estimation methods DSTA significantly enhances performance achieving an 8.9 mAP improvement on PoseTrack2017. Furthermore our approach either surpasses or is on par with the state-of-the-art heatmap-based multi-frame human pose estimation methods. Project page: https://github.com/zgspose/DSTA.