region op• Data kinds: region → region
• Call: fullseye.apply(img, "fill_holes", a=0.5, b=0.5) (the 2-D model is one image plus two scalar knobs a,b∈[0,1])
• HALCON equivalent: fill_up (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.*
*Knob a does not change the output (measured: identical at 0.1 / 0.5 / 0.9).*
*Knob b does not change the output (measured: identical at 0.1 / 0.5 / 0.9).*
Stages (the ops that come before → this op, left to right):
▸ fill_holes: stages (docs site)
On other images (synthetic scene / photo / coins. Top row: inputs, bottom row: their outputs. Knobs at default):
▸ fill_holes: other inputs (docs site)
Fills holes within a region. Equivalent to HALCON's `fill_up` (Fill up holes in regions.).
> The detailed description below is the original text — the summary and the headings are translated.
`a, b は未使用。前景に完全に囲まれた背景画素（穴）をすべて前景に変える（scipy.ndimage.binary_fill_holes`）。画像端に接する背景は穴とみなされないため埋まらない。
連結性: 穴の判定に使う背景は 4 連結(`scipy.ndimage.binary_fill_holes` の既定)。斜めだけで繋がった背景は繋がっているとみなさないので、市松模様では内側の背景画素がすべて穴として埋まる(8x8 で 32 -> 50 画素。実測して scipy の 4 連結参照と位置まで一致、8 連結とは不一致)。第 2 実装がここで別の連結性を選び、差分検査で露見した。
• gallery2d_region 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.
threshold 0.50 0.50 fill_holes 0.50 0.50
▸ Load this pipeline · Load & run
• gallery2d_region — py -3.11 examples/gallery2d_region.py
• poc_cell_counting — py -3.11 examples/poc_cell_counting.py
• poc_document_scan — py -3.11 examples/poc_document_scan.py
• poc_leaf_disease_area — py -3.11 examples/poc_leaf_disease_area.py
• poc_mesh_quality_repair — py -3.11 examples/poc_mesh_quality_repair.py
• poc_real_coin_metrology — py -3.11 examples/poc_real_coin_metrology.py
• poc_symmetry_restoration — py -3.11 examples/poc_symmetry_restoration.py
region as input)identity · reg_erode · reg_dilate · reg_open · reg_close · select_largest · remove_small · invert_region
region)reg_erode · reg_dilate · reg_open · reg_close · select_largest · remove_small · invert_region · dist_transform
*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.