morphology op• Data kinds: image → image
• Call: fullseye.apply(img, "local_thickness", a=0.5, b=0.5) (the 2-D model is one image plus two scalar knobs a,b∈[0,1])
*The figure is the actual output on a synthetic 128×128 input. Left: input, right: output. Point clouds are drawn as a top-down scatter (brightness = z), 1-D series as a line plot, volumes as the maximum-intensity projection along z, videos as the middle frame, complex images as magnitude; return values that are not pictures are shown as the values themselves.*
Sweeping knob a (0.1 / 0.5 / 0.9, the other knob at its default):
▸ local_thickness: knob a sweep (docs site)
Sweeping knob b (0.1 / 0.5 / 0.9, the other knob at its default):
▸ local_thickness: knob b sweep (docs site)
On other images (synthetic scene / photo / coins. Top row: inputs, bottom row: their outputs. Knobs at default):
▸ local_thickness: other inputs (docs site)
*The 4th column is a colour (H,W,3) input. This op handles colour without crossing channels (it does not convolve the colour channel as a third spatial axis).*
> This operator's description has not been translated yet. The original text follows as it is.
各前景画素に「そこを覆える最大の円の直径」を入れて返す(局所肉厚)。
明るい側を前景とみなす閾値が `b(0.1〜0.9)。a` が測る上限の半径(1〜12 画素)で、
出力はその上限で割って `[0,1] に収めてある —— **絶対値が要るときは a` から
上限を逆算して掛け戻すこと**。
粒径・気孔径・肉厚を「1 枚の地図」として出す古典的な量で、モルフォロジーの
粒度測定(granulometry)と同じもの: ある画素の値が `r なら、その画素は半径 r` の
円による開処理を生き残る。距離変換で内接円の半径を求め、半径の大きい順にその円が
覆う範囲へ書き込む、という素直な実装。
適用条件: (1) 前景を 1 つの閾値で決めるので、照明むらがあると太さが場所によって
偏る —— 先に `local_threshold などで平坦化すること。(2) 上限 a` より太い構造は
上限で頭打ちになる(飽和しているかは出力の最大値が 1.0 に貼りついているかで分かる)。
(3) 画素単位の量なので、直径が 3 画素を切ると量子化の刻みが 30% を超える。
用途: 鋳巣・発泡体の気孔径分布、粉体の粒径、薄肉部の検出、繊維の太さ。
3-D 版は `ops3d の vol_wall_thickness`。HALCON に対応する単体 op は無い。
• gallery2d_morphology family guide
• 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.
The program below has been verified to run (same input as the figure). In Studio's help this block becomes buttons that load and run it on the spot.
local_thickness 0.35 0.50
▸ Load this pipeline · Load & run
• gallery2d_morphology — py -3.11 examples/gallery2d_morphology.py
• poc_bone_trabecular_thickness — py -3.11 examples/poc_bone_trabecular_thickness.py
image as input)identity · gaussian · mean_box · bilateral · unsharp · median · min_filter · max_filter
morphology)gerode · gdilate · gopen · gclose · runlength_smear · tophat · bothat · morph_grad
*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.