sk_enhance_contrast — 2D gray op

Data kinds: imageimage

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

Usage

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

局所コントラスト強調。各画素を、局所近傍の最大値と最小値のどちらに近いかで判定し、近い方の値へ置き換える —— 中間的な値を持つ画素が両極端に押し出され、見かけ上のコントラストが上がる(2 値化に近い効果が出ることもある)。

HALCON に直接対応するものは無い。実装は `filters.rank.enhance_contrast(_u8s(v), disk(1+int(a*3)))` を 255 で割ったもの —— a は円盤半径を 1〜4 に振る。b は未使用。

Detailed usage guide

gallery2d_gray_arith 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_gray_arithpy -3.11 examples/gallery2d_gray_arith.py

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

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

Same category (gray)

gamma · invert · scale_clip · equalize · sigmoid · clahe · sk_adapthist · sk_autolevel


*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.