Papers › What Matters in Unsupervised Optical Flow

What Matters in Unsupervised Optical Flow

8 Jun 2020ECCV 2020 8arXiv:2006.04902archive 2025-07-28

Rico Jonschkowski, Austin Stone, Jonathan T. Barron, Ariel Gordon, Kurt Konolige, Anelia Angelova

We systematically compare and analyze a set of key components in unsupervised optical flow to identify which photometric loss, occlusion handling, and smoothness regularization is most effective. Alongside this investigation we construct a number of novel improvements to unsupervised flow models, such as cost volume normalization, stopping the gradient at the occlusion mask, encouraging smoothness before upsampling the flow field, and continual self-supervision with image resizing. By combining the results of our investigation with our improved model components, we are able to present a new unsupervised flow technique that significantly outperforms the previous unsupervised state-of-the-art and performs on par with supervised FlowNet2 on the KITTI 2015 dataset, while also being significantly simpler than related approaches.

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check_model_frozen junbongjang/contour-tracking/src/contour_flow_main.py community (archive-listed) unverified Apache-2.0 (permissive) · 36e04cd3ded65746 · report
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corr_2d_loss junbongjang/contour-tracking/src/tracking_utils.py community (archive-listed) unverified Apache-2.0 (permissive) · e3a04fdb34e68bb4 · report
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get_image_name junbongjang/contour-tracking/src/preprocessing/MATLAB_tracking_points.py community (archive-listed) unverified Apache-2.0 (permissive) · 70452baab57f53ae · report
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normalize_features junbongjang/contour-tracking/src/contour_flow_model.py community (archive-listed) unverified Apache-2.0 (permissive) · d0f7630cddfa3a3a · report
normalize_points junbongjang/contour-tracking/src/metrics.py community (archive-listed) unverified Apache-2.0 (permissive) · d654e53ca581da7f · report
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robust_l2 junbongjang/contour-tracking/src/tracking_utils.py community (archive-listed) unverified Apache-2.0 (permissive) · 8f9b339cc1ef3aa1 · report
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Tasks

Occlusion HandlingOptical Flow Estimation

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Optical Flow Estimation Sintel Clean unsupervised UFlow Average End-Point Error 5.21 #5 of 5 Archive leaderboard report
Optical Flow Estimation Sintel Final unsupervised UFlow Average End-Point Error 6.50 #5 of 5 Archive leaderboard report

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