topology_signature — 3D `medial` op

• Data kinds: voxel → table

• Call: import fullseye as fs; fs.ledger.topology_signature(skeleton) (to call the implementation directly, import medial; medial.topology_signature(skeleton); from the registry, ops3d.get("topology_signature"))

Usage

Build a topology descriptor from the 26-neighbourhood degrees of a skeleton. Returns the counts of end points, junctions, ordinary points and isolated points.

> The detailed description below is the original text — the summary and the headings are translated.

各骨格 voxel について 26 近傍にある骨格 voxel 数(次数)を数え、

次数 1 = 端点(endpoint)

次数 2 = 通常点(骨格の途中)

次数>=3 = 分岐点(branch)

次数 0 = 孤立点(isolated)

に分類する。個数は平行移動・回転(90 度)不変で、形状の位相を粗く要約する記述子になる。

注意(honest): 26 近傍の次数は、分岐近傍で対角隣接により過大に数えられることがある(離散

骨格の既知の性質)。端点数は各枝の末端で厳密だが、分岐点数はやや過大側に振れうる。

Args:

skeleton: 骨格 voxel(bool / 0-1 の 3D)。

Returns:

dict: endpoints, branches, normal, isolated, total(骨格 voxel 総数),

degree_hist(次数 -> 個数)。

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.

Runnable examples (verified samples that actually call this op)

• medial_topology — py -3.11 examples_3d/medial_topology.py

Ops the type connects to (they accept `table` as input)

fuse_to_voxel · mesh_select_lod

Same category (`medial`)

distance_ridge · skeletonize_vol · medial_axis_points · medial_match · skeleton_junctions3d · skeleton_endpoints3d · skeleton_prune3d · skeleton_branches3d

*Provenance: medial.py — 3D operator registry. This per-op note is generated by tools/opdocs.py md (do not hand-edit).*

topology_signature — 3D medial op