area_center — 2D `features` op

• Data kinds: region → match

• Call: fullseye.apply(img, "area_center", a=0.5, b=0.5) (the 2-D model is one image plus two scalar knobs a,b∈[0,1])

• HALCON equivalent: area_center (the HALCON reference is a useful guide to its meaning and parameters)

Usage

> This operator's description has not been translated yet. The original text follows as it is.

領域の面積と重心を、解像度に依らない正規化済みの 3 成分ベクトル

(面積比 = 面積/画像画素数、正規化重心行、正規化重心列)として返す。1

スカラーでは (Area, Row, Column) を表せないため、`match` ソート(1 次元

ベクトル、`ncc_locate` と同じ形)で返す点が他の region 特徴 op と異なる。

領域が空のときは (0, 0.5, 0.5)(面積ゼロ・中心=画像中心)を返す fail-soft

仕様。HALCON の `area_center`（Area and center of regions.）に相当。

`a, b` は未使用。

Detailed usage guide

• gallery2d_features family guide

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)

• gallery2d_features — py -3.11 examples/gallery2d_features.py

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

identity

Same category (`features`)

blob_count · area_frac · count_contours · total_length · vol_count · sk_euler · sk_entropy_feat · sk_blur_effect

*Provenance: ops.py — 2D operator registry. This per-op note is generated by tools/opdocs.py md (do not hand-edit).*

area_center — 2D features op