region op• Data kinds: region → region
• Call: fullseye.apply(img, "erosion_circle", a=0.5, b=0.5) (the 2-D model is one image plus two scalar knobs a,b∈[0,1])
• HALCON equivalent: erosion_circle (the HALCON reference is a useful guide to its meaning and parameters)
Binary erosion with a disk-shaped structuring element (`ndimage.binary_erosion). The most basic binary morphological operation, eroding the foreground region from its outer boundary to shrink it. Corresponds to HALCON's erosion_circle` (Erode a region with a circular structuring element).
> The detailed description below is the original text — the summary and the headings are translated.
`a が構造要素の半径を 1〜4 の範囲(_rad(a))で振る。b` はこの
バックエンドの二値モルフォロジー op(erosion/dilation/opening/closing の
円形・矩形いずれも)に共通して未使用。
• 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.
• gallery2d_region — py -3.11 examples/gallery2d_region.py
region as input)identity · reg_erode · reg_dilate · reg_open · reg_close · fill_holes · select_largest · remove_small
region)reg_erode · reg_dilate · reg_open · reg_close · fill_holes · select_largest · remove_small · invert_region
*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.