morphology op• Data kinds: image → image
• Call: fullseye.apply(img, "gclose", a=0.5, b=0.5) (the 2-D model is one image plus two scalar knobs a,b∈[0,1])
• HALCON equivalent: gray_closing (the HALCON reference is a useful guide to its meaning and parameters)

*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):
▸ gclose: knob a sweep (docs site)
Sweeping knob b (0.1 / 0.5 / 0.9, the other knob at its default):
▸ gclose: knob b sweep (docs site)
On other images (synthetic scene / photo / coins. Top row: inputs, bottom row: their outputs. Knobs at default):
▸ gclose: other inputs (docs site)
*No colour (H,W,3) input is shown: this op treats the colour channel as a third spatial axis (it crosses channels). Call it per channel.*
Grayscale closing (dilation followed by erosion). Equivalent to HALCON's `gray_closing` (Perform a gray value closing on an image.).
> 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 が**構造要素の形**を選ぶ: b <= 0.5 で正方形(2026-09-17 までの挙動、分離可能なので最速)、以降 十字 / 円板 / 水平線。円板は HALCON の gen_disc_se` に、水平線は方向性のある欠陥(横筋・スジ)を残したまま縦方向だけ均すのに使う。★正方形以外は footprint 経由になるので目に見えて遅い。暗い小さな欠け(ノイズ状の暗点)を埋めつつ、大きな暗域の形はほぼ保つ。
Knobs (measured): `a` acts in discrete steps; it switches at a ≈ 0.25、0.49、0.75 (measured on a sweep of step 0.02).
• 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.
gclose 0.35 0.50
▸ Load this pipeline · Load & run
• gallery2d_morphology — py -3.11 examples/gallery2d_morphology.py
image as input)identity · gaussian · mean_box · bilateral · unsharp · median · min_filter · max_filter
morphology)gerode · gdilate · gopen · runlength_smear · tophat · bothat · morph_grad · persistence_map
*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.