keypoints_uv_to_points — REPRCONV keypoint op

• Data kinds: keypoints → points

• Call: import fullseye as fs; fs.ledger.keypoints_uv_to_points(keypoints, z=0.0) (to call the implementation directly, import reprconv; reprconv.keypoints_uv_to_points(keypoints, z=0.0); from the registry, opsreprconv.get("keypoints_uv_to_points"))

Usage

Image coordinates (N,2) = (u, v) → a point set (N,3) = (z, y, x). The exit from keypoints.

The axis convention is written in the op name because in this repo the producer of keypoints, match3d.project_points, returns (u, v) = (column, row), and the producer of points, fuse3d.to_points(voxel), returns (z, y, x) -- connecting them naively as "the first 2 columns" swaps rows and columns without any exception or NaN. Here y = v and x = u are swapped explicitly before passing on.

Round trip with points_zyx_to_keypoints_uv is bit-identical (in the direction where z is passed).

Args:

keypoints: (N, 2) (u, v).

z: z of the plane to place them on (a scalar, or an (N,) array).

Returns:

(N, 3) float64 (z, y, x).

Raises:

ValueError: invalid shape / non-finite / length of z does not match.

References (sample data, literature)

• Sample-data catalog (download URLs / licences) — 2-D uses skimage.data (BSD/public domain) plus synthetic images; 3-D lists download URLs for real data sources (Stanford, PDS, …).

• Operator provenance and references — the sources of the research/methods this op family came from.

• The canonical algorithm (author, year) and its uses are named in the family usage guide above.

Runnable examples (verified samples that actually call this op)

• representation_roundtrip — py -3.11 examples/representation_roundtrip.py

Ops the type connects to (they accept points as input)

points_zyx_to_keypoints_uv · points_to_position · select_points · flow_apply · points_to_gaussians

Same category (keypoint)

points_zyx_to_keypoints_uv · keypoints_to_image2d · keypoints_from_image2d · position_to_points · points_to_position


*Provenance: reprconv.py — REPRCONV operator registry. This per-op note is generated by tools/opdocs.py md (do not hand-edit).*

© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.