Papers › I Can't Believe It's Not Scene Flow!

I Can't Believe It's Not Scene Flow!

7 Mar 2024arXiv:2403.04739archive 2025-07-28

Ishan Khatri, Kyle Vedder, Neehar Peri, Deva Ramanan, James Hays

Current scene flow methods broadly fail to describe motion on small objects, and current scene flow evaluation protocols hide this failure by averaging over many points, with most drawn larger objects. To fix this evaluation failure, we propose a new evaluation protocol, Bucket Normalized EPE, which is class-aware and speed-normalized, enabling contextualized error comparisons between object types that move at vastly different speeds. To highlight current method failures, we propose a frustratingly simple supervised scene flow baseline, TrackFlow, built by bolting a high-quality pretrained detector (trained using many class rebalancing techniques) onto a simple tracker, that produces state-of-the-art performance on current standard evaluations and large improvements over prior art on our new evaluation. Our results make it clear that all scene flow evaluations must be class and speed aware, and supervised scene flow methods must address point class imbalances. We release the evaluation code publicly at https://github.com/kylevedder/BucketedSceneFlowEval.

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kylevedder/bucketedscenefloweval officialmentioned in papermentioned on GitHubMIT report
kylevedder/SceneFlowZoo mentioned on GitHubpytorchMIT report

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align_vector_to_another kylevedder/bucketedscenefloweval/bucketed_scene_flow_eval/datastructures/line_mesh.py official repository ran MIT (permissive) · 5c5482d289a07f32 · report
make_image_pixel_coordinate_grid kylevedder/bucketedscenefloweval/bucketed_scene_flow_eval/datastructures/pointcloud.py official repository ran MIT (permissive) · 6fa9a0952102a0c3 · report
normalized kylevedder/bucketedscenefloweval/bucketed_scene_flow_eval/datastructures/line_mesh.py official repository ran fingerprinted MIT (permissive) · a9bf78961f9edbd5 · report
ray_triangle_intersect kylevedder/bucketedscenefloweval/flow_lab/flow_lab.py official repository ran MIT (permissive) · 76dac6858417dbfb · report
to_fixed_array kylevedder/bucketedscenefloweval/bucketed_scene_flow_eval/datastructures/pointcloud.py official repository ran MIT (permissive) · fb9040070a43fabf · report
from_fixed_array kylevedder/bucketedscenefloweval/bucketed_scene_flow_eval/datastructures/pointcloud.py official repository unverified MIT (permissive) · 8932de372132539f · report
build_metadata kylevedder/SceneFlowZoo/av2_scene_flow_competition_submit.py community (archive-listed) unverified MIT (permissive) · 75b0424130303c2c · report
load_json kylevedder/SceneFlowZoo/data_prep_scripts/flatten_non_causal.py community (archive-listed) unverified MIT (permissive) · a9e13d8e6c527e20 · report

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