geometry op• Data kinds: region → region
• Call: fullseye.apply(img, "affine_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: affine_trans_region (the HALCON reference is a useful guide to its meaning and parameters)
Applies an affine transform (rotation + shear) to a region. Transforms it as a continuous value using the same `affine branch of _sh_geom as affine_trans_image, then re-binarizes it at 0.5 via _rebinarise` and returns it as a {0,1} region (to remove intermediate values produced by geometric-transform interpolation). a sets the rotation angle (-20 to +20 degrees), and b sets the shear amount.
> The detailed description below is the original text — the summary and the headings are translated.
HALCON の `affine_trans_region`（領域に任意のアフィン 2D 変換を適用する演算）に相当する近似。
• gallery2d_geometry 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_geometry — py -3.11 examples/gallery2d_geometry.py
region as input)identity · reg_erode · reg_dilate · reg_open · reg_close · fill_holes · select_largest · remove_small
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.