Research Note

Point Tracking Task Record

Given a video and a query that contains a frame index and two-dimensional location, a point tracker estimates the corresponding two-dimensional point location across fram

Aug 4, 20262 min readBy Dalton Anderson
In this article

Point Tracking Task Record

Formal task

Given a video and a query that contains a frame index and two-dimensional location, a point tracker estimates the corresponding two-dimensional point location across frames. Modern tracking-any-point systems also estimate whether the queried surface point is visible.

The CoTracker3 paper additionally predicts confidence about whether a track is close to the unknown ground truth under the paper's training definition. Confidence is not ground truth and should be calibrated for the intended workflow.

Terms

TermWorking definition
Query pointA selected image location in a particular frame
TrajectoryThe estimated location of the same physical surface point through time
VisibilityWhether the surface point can be observed in a frame
OcclusionA temporary obstruction between the surface point and camera
Out of frameThe point projects outside the captured image
Re-entryThe point becomes visible again after occlusion or leaving the frame
Sparse trackingA limited set of chosen points
Quasi-dense trackingA larger grid or collection of points, short of a per-pixel field
Online modeCausal or sliding-window processing intended for sequential input
Offline modeProcessing that can use more of the video and may track both temporal directions

What the output does not contain

A point trajectory does not automatically identify an object, classify a person, assign a persistent object identity, produce a segmentation mask, infer three-dimensional position, estimate camera pose, or predict intent.

Those results may be built from point tracks and other components. The pipeline and its errors must be evaluated as a whole.

Common hard cases

Point trackers can drift on repeated or weak texture, lose a trajectory during fast motion or blur, confuse reflections, mishandle deformation, misclassify visibility, or fail to recover after a long occlusion.

The CoTracker3 project page explicitly shows featureless sky and water as failure cases. That evidence is more useful than a claim that the model can track any visible pixel in every scene.

Metric boundary

TAP-Vid evaluates localization and occlusion with declared query modes and resolution conventions. A metric is interpretable only with the dataset, query sampling, threshold, visibility rule, preprocessing, model mode, and code version used to compute it.

Sources

Follow the evidence.

  1. youtu.be: BNTcjZ0Ym38youtu.be
  2. ai.meta.com: sam2ai.meta.com
  3. proceedings.neurips.cc: 58168e8a92994655d6da3939e7cc0918 Abstract Datasets and Benchmarksproceedings.neurips.cc
  4. arxiv.org: 2410arxiv.org
  5. open.spotify.com: 26JgnnwjvK5vYIdRofV8ntopen.spotify.com
  6. github.com: co trackergithub.com
  7. cotracker3.github.iocotracker3.github.io
  8. NIST AI Risk Management Frameworknist.gov
  9. vggsfm.github.iovggsfm.github.io
  10. daltonanderson.ghost.io: metas cotracker 3 a leap in ai object trackingdaltonanderson.ghost.io
  11. arxiv.org: 1803arxiv.org
  12. ecva.net: 3526 ECCV 2020 paperecva.net
  13. github.com: tapnetgithub.com
  14. raw.githubusercontent.com: LICENSEraw.githubusercontent.com
  15. tapvid.github.iotapvid.github.io
  16. NIST Privacy Frameworknist.gov
  17. arxiv.org: 1504arxiv.org
  18. openaccess.thecvf.com: Karaev CoTracker3 Simpler and Better Point Tracking by Pseudo Labelling Real Videos ICCV 2025 paperopenaccess.thecvf.com

From this episode

Two useful next steps.

Research Note · 1 min

Video Tracking Task Selection Record

Choose a video method by defining the unit that must persist and the output consumed by the workflow. A demonstration should not determine the task.

Research Note · 1 min

Point Tracking Test Set Framework

Define the target camera, scene, motion, subject, duration, resolution, frame rate, and operating condition before collecting clips. Split by source sequence, capture ses

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