geometry op• Data kinds: region → region
• Call: fullseye.apply(img, "zoom_region", a=0.5, b=0.5) (the 2-D model is one image plus two scalar knobs a,b∈[0,1])
• HALCON equivalent: zoom_region (the HALCON reference is a useful guide to its meaning and parameters)
Zooms the region isotropically (same scale on both axes). Scales it about the center by a factor `s = 0.7+0.6a (0.7x to 1.3x), fills out-of-bounds areas by reflection, then converts back to a binary region via _rebinarise` with a 0.5 threshold. b is unused.
> The detailed description below is the original text — the summary and the headings are translated.
HALCON の `zoom_region(領域を指定倍率でズームする演算)に相当する近似。縦横独立の倍率を持つ zoom_image_factor` とは異なり単一倍率のみ。
• 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.