r3_polar_trans_region — 2D region op

Data kinds: regionregion

Call: fullseye.apply(img, "r3_polar_trans_region", a=0.5, b=0.5) (the 2-D model is one image plus two scalar knobs a,b∈[0,1])

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

Usage

Remaps the region to polar coordinates centred on its centroid (equivalent to HALCON `polar_trans_region`).

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

出力の行が半径軸(0〜`rmax)、列が角度軸(0〜angle_end)にあたる。a(0〜1)は半径方向の広がり(rmax は重心から最遠画素までの距離に 0.25+0.75*a を掛けたもの)、b(0〜1)は角度方向の掃引幅(angle_end = 2*pi*(0.25+0.75*b)`)を振る。最近傍サンプリング。出力の形状は入力と同じ。

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

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

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

Same category (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.