elliptic_axis — 2D `features` op

• Data kinds: region → feature

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

• HALCON equivalent: elliptic_axis (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.

領域に等価な楕円（equivalent ellipse、慣性モーメントが一致する楕円）の長軸と短軸の比（アスペクト比）を返す。`skimage.measure.regionprops の axis_major_length/axis_minor_length` から計算し、/10 でおおよそ [0,1] 程度のスケールに収める（正規化ではないため、非常に細長い領域では 1 を超えうる）。a, b は未使用。

HALCON の `elliptic_axis（等価楕円の長半径・短半径そのもの 2 つの長さを返す演算）とは異なり、この実装は長さではなく比（アニソメトリー、anisometry` と同じ metric）だけを 1 スカラーで返す近似。

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 `feature` 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).*

elliptic_axis — 2D features op