mirror_region — 2D geometry op

Data kinds: regionregion

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

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

Usage

Flips (mirrors) the region. The axis is chosen by a: a<0.34 flips vertically (`flipud), 0.34<=a<0.67 flips horizontally (fliplr), otherwise it transposes (diagonal flip, x.T). b is unused. Since flipping doesn't change values, _rebinarise` is effectively a no-op.

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

HALCON の `mirror_region`(軸を指定して領域を反射する演算)に相当。HALCON は軸位置を任意に指定できるが、この実装は画像中心を通る 3 種類の軸(縦/横/対角)に固定されている近似。

Detailed usage guide

gallery2d_geometry 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_geometrypy -3.11 examples/gallery2d_geometry.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 (geometry)

rotate_img · rescale_img · affine_warp · sk_swirl · mirror_image · transpose_region · rotate_image · zoom_image_factor


*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.