morph_grad — 2D morphology op

• Data kinds: image → image

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

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

Usage

Morphological gradient (dilation minus erosion). Equivalent to HALCON's `gray_range_rect` (Determine the gray value range within a rectangle.).

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

`a が構造要素の一辺を 3,5,7,9（_k(a)）に振る。b は未使用。窓内の最大値と最小値の差を返すため、エッジ検出フィルタ（Sobel 等）に似た働きをするが方向を持たない。結果は _norm` で正規化される。

Detailed usage guide

• gallery2d_morphology 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_morphology — py -3.11 examples/gallery2d_morphology.py

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

identity · gaussian · mean_box · bilateral · unsharp · median · min_filter · max_filter

Same category (morphology)

gerode · gdilate · gopen · gclose · tophat · bothat · sk_area_opening · cv_open

*Provenance: ops.py — 2D 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.