edges op• Data kinds: image → image
• Call: fullseye.apply(img, "sk_scharr", a=0.5, b=0.5) (the 2-D model is one image plus two scalar knobs a,b∈[0,1])
• HALCON equivalent: edges_image (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).*
Scharr gradient magnitude. Directly calls skimage's `filters.scharr`, returning the gradient magnitude obtained by combining the responses of the horizontal and vertical Scharr kernels (3x3).
> The detailed description below is the original text — the summary and the headings are translated.
HALCON の edges_image(Extract edges using Deriche, Lanser, Shen, or Canny filters.)に相当(近似。アルゴリズムは異なる)。Sobel より回転対称性(方向によらず応答が均一)が良いとされるカーネル。a, b は未使用 —— スケールや閾値の調整点が無く、常に固定カーネルで一発計算する軽量なエッジ検出。
• gallery2d_edges 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.
sk_scharr 0.40 0.50
▸ Load this pipeline · Load & run
• gallery2d_edges — py -3.11 examples/gallery2d_edges.py
image as input)identity · gaussian · mean_box · bilateral · unsharp · median · min_filter · max_filter
edges)sobel_mag · prewitt_mag · roberts_mag · dog · grad_dir · log · corner_response · sk_farid
*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.