features op• Data kinds: region → feature
• Call: fullseye.apply(img, "get_region_thickness", a=0.5, b=0.5) (the 2-D model is one image plus two scalar knobs a,b∈[0,1])
• HALCON equivalent: get_region_thickness (the HALCON reference is a useful guide to its meaning and parameters)

*The figure is the real output on a synthetic 128×128 input. Left: input, right: output (a non-image return value is shown as the value itself).*
An approximation of region thickness: `2 x max inscribed circle radius / max side length (twice the maximum of distance_transform_edt, normalized by the image size). Unlike HALCON's get_region_thickness` (Access the thickness of a region along the main axis.), which defines a 'thickness profile along the main axis,' this is a simplification that only looks at the direction-independent, global maximum inscribed radius (information about the main-axis direction is lost).
> The detailed description below is the original text — the summary and the headings are translated.
`a, b` は未使用。
• gallery2d_features 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.
The program below has been verified to run (same input as the figure). In Studio's help this block becomes buttons that load and run it on the spot.
threshold 0.50 0.50 get_region_thickness 0.50 0.50
▸ Load this pipeline · Load & run
• gallery2d_features — py -3.11 examples/gallery2d_features.py
feature as input)features)blob_count · area_frac · count_contours · total_length · vol_count · sk_euler · sk_entropy_feat · sk_blur_effect
*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.