features op• Data kinds: image → feature
• Call: fullseye.apply(img, "xsk_blob_doh", a=0.5, b=0.5) (the 2-D model is one image plus two scalar knobs a,b∈[0,1])
Number of detected blobs (speckle-like structures) (detected using one of LoG/DoG/DoH).
> The detailed description below is the original text — the summary and the headings are translated.
skimage.feature の Laplacian of Gaussian(LoG)/ Difference of
Gaussian(DoG)/ Determinant of Hessian(DoH)のいずれか(このコードは
3 種を共通実装しており、どれを使うかは呼び出し元がどの op 名で
登録したか —— `xsk_blob_log / xsk_blob_dog / xsk_blob_doh`
—— で決まる)を用いてブロブを検出し、その個数をそのまま返す
(feature 出力)。
`a が探索する最大スケール max_sigma` を 5〜25 の範囲で振る
(大きいほど大きなブロブまで拾う)。`b` が検出しきい値
`threshold` を 0.02〜0.17 で振る(小さいほど弱いブロブまで拾い、
検出数が増えやすい)。3 手法は速度・精度が異なる(LoG が最も正確
だが遅く、DoH はエッジに強い一方、小さいブロブを苦手とする、等)。
• 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.
• 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.