remove_small — 2D region op

Data kinds: regionregion

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

HALCON equivalent: select_shape (the HALCON reference is a useful guide to its meaning and parameters)

Usage

Removes small connected regions based on area. Equivalent to HALCON's `select_shape` (Choose regions with the aid of shape features.).

> The detailed description below is the original text — the summary and the headings are translated.

`a が除去のしきい値(画素数)を、画像全体の画素数に対する割合 0.01〜0.16(0.01+0.15a) * 画素数)として振る。b は未使用。しきい値以上の面積を持つ連結成分だけを残す。連結性は scipy label` の既定(4連結)。

Detailed usage guide

gallery2d_region 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_regionpy -3.11 examples/gallery2d_region.py

quickstartpy -3.11 examples/quickstart.py

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

identity · reg_erode · reg_dilate · reg_open · reg_close · fill_holes · select_largest · invert_region

Same category (region)

reg_erode · reg_dilate · reg_open · reg_close · fill_holes · select_largest · 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.