arithmetic op• Data kinds: image → image
• Call: fullseye.apply(img, "cos_image", a=0.5, b=0.5) (the 2-D model is one image plus two scalar knobs a,b∈[0,1])
• HALCON equivalent: cos_image (the HALCON reference is a useful guide to its meaning and parameters)
> This operator's description has not been translated yet. The original text follows as it is.
`(cos(2πx) + 1) / 2 による周期 LUT。sin_image` と位相が π/2 ずれた
版で、x=0 で最大(1)、x=0.5 で最小(0)に達してから再び上がる。HALCON の
`cos_image`(Calculate the cosine of an image.)の代役。
`a, b は未使用。sin_image` と同じく非単調・非可逆な周期写像なので、
一般のコントラスト補正ではなく擬似的な等高線表現などに使う。
• 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
arithmetic)abs_image · sqrt_image · exp_image · log_image · sin_image · asin_image · acos_image · atan_image
*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.