label_components — 3D regionprops op

Data kinds: voxellabels

Call: import fullseye as fs; fs.ledger.label_components(vol, connectivity: 'int' = 26) (to call the implementation directly, import regionprops3d; regionprops3d.label_components(vol, connectivity: 'int' = 26); from the registry, ops3d.get("label_components"))

Return value through the ledger: fullseye.ledger.label_components(...) returns **only the declared out type labels** (the underlying function also returns auxiliary values). When you need what was dropped, use fullseye.ledger.label_components.raw(...) or call regionprops3d.label_components directly.

• Underlying return: (labels, n) → labels

Usage

Label a 3-D binary volume into connected components.

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

Parameters

----------

vol : array_like

bool または 0/1 の 3D 配列。

connectivity : int

6(面) / 18(面+辺) / 26(面+辺+角)のいずれか。

Returns

-------

labels : ndarray(int)

vol と同形状。背景 0、各連結成分に 1..n のラベル。

n : int

連結成分数。

補足:

• 入力は `astype(bool)` で二値化する。0 以外はすべて前景で、float の NaN も True(前景)になる点に注意。

• 軸順は (z, y, x) = numpy の配列軸順。`labels の dtype は scipy.ndimage.label` の返す整数型(通常 int32)。前景が無い/空配列なら int32 のゼロ配列と 0 を返す。

• ラベル番号の付与順は scipy の走査順で、体積順ではない。

• Raises `ValueError: 3 次元でない入力、connectivity` が 6/18/26 以外。

• 接触している物体は 1 成分に融合する。分離が要るなら前段で `morph_erode3d / morph_open3dvol_watershed` で切る。

• 後段: `region_props(計測)、largest_component / filter_by_volume(選別)、vol_select_labels(特徴でふるい)、vol_colorize_labels`(可視化)。

Background guides (the physics and conventions behind this op)

measurement_uncertainty — 計測の不確かさと校正の知識 — 「測れている」を主張するために

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)

region_props_3dpy -3.11 examples_3d/region_props_3d.py

watershed3dpy -3.11 examples_3d/watershed3d.py

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

fuse_to_voxel · vol_region_props

Same category (regionprops)

region_props · largest_component · filter_by_volume · inner_box3 · vol_label · vol_region_props


*Provenance: regionprops3d.py — 3D 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.