gray op• Data kinds: image → image
• Call: fullseye.apply(img, "xsp_detrend_flatten", a=0.5, b=0.5) (the 2-D model is one image plus two scalar knobs a,b∈[0,1])
A flattening filter that removes the linear trend (slope) of the whole image separately along the vertical and horizontal directions, then normalizes.
> The detailed description below is the original text — the summary and the headings are translated.
`scipy.signal.detrend を列方向・行方向の順に適用し、各行/各列の線形回帰成分を差し引く。a, b は未使用。照明ムラなど画像全体に乗った緩やかな傾斜を除去し、局所コントラストを見やすくする用途。結果は符号付きなので*0.5+0.5` で [0,1] に写像し直している。
• gallery2d_gray_arith 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_gray_arith — py -3.11 examples/gallery2d_gray_arith.py
image as input)identity · gaussian · mean_box · bilateral · unsharp · median · min_filter · max_filter
gray)gamma · invert · scale_clip · equalize · sigmoid · clahe · sk_adapthist · sk_enhance_contrast
*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.