Papers › Particle Video Revisited: Tracking Through Occlusions Using Point Trajectories

Particle Video Revisited: Tracking Through Occlusions Using Point Trajectories

8 Apr 2022arXiv:2204.04153archive 2025-07-28

Adam W. Harley, Zhaoyuan Fang, Katerina Fragkiadaki

Tracking pixels in videos is typically studied as an optical flow estimation problem, where every pixel is described with a displacement vector that locates it in the next frame. Even though wider temporal context is freely available, prior efforts to take this into account have yielded only small gains over 2-frame methods. In this paper, we revisit Sand and Teller's "particle video" approach, and study pixel tracking as a long-range motion estimation problem, where every pixel is described with a trajectory that locates it in multiple future frames. We re-build this classic approach using components that drive the current state-of-the-art in flow and object tracking, such as dense cost maps, iterative optimization, and learned appearance updates. We train our models using long-range amodal point trajectories mined from existing optical flow data that we synthetically augment with multi-frame occlusions. We test our approach in trajectory estimation benchmarks and in keypoint label propagation tasks, and compare favorably against state-of-the-art optical flow and feature tracking methods.

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fetch_optimizer aharley/pips/train2.py official repository unverified MIT (permissive) · db83affa17361b10 · report
flood_fill_hull aharley/pips/make_occlusions.py official repository unverified MIT (permissive) · 768d8abfae882911 · report
load aharley/pips/saverloader.py official repository unverified MIT (permissive) · a9f4f1b5557431c4 · report
readImage aharley/pips/flyingthingsdataset.py official repository unverified MIT (permissive) · 8dc07cad5c147d48 · report
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Motion EstimationObject TrackingOptical Flow EstimationSand

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