smoothing op• Data kinds: image → image
• Call: fullseye.apply(img, "isotropic_diffusion", a=0.5, b=0.5) (the 2-D model is one image plus two scalar knobs a,b∈[0,1])
• HALCON equivalent: isotropic_diffusion (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).*
The implementation is a simple Gaussian blur (`gaussian_filter, sigma 0.5+2.5*a). Since the solution of the isotropic diffusion equation is mathematically equivalent to convolution with a Gaussian kernel, this approximation is theoretically valid (it has no edge-preserving effect like anisotropic diffusion, and smooths uniformly regardless of direction). Corresponds to HALCON's isotropic_diffusion` (Perform an isotropic diffusion of an image).
> The detailed description below is the original text — the summary and the headings are translated.
`a がシグマ(拡散時間に相当)を 0.5〜3.0 の範囲で振る。b` は未使用。
• gallery2d_smoothing_rank 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.
isotropic_diffusion 0.35 0.50
▸ Load this pipeline · Load & run
• gallery2d_smoothing_rank — py -3.11 examples/gallery2d_smoothing_rank.py
image as input)identity · gaussian · mean_box · bilateral · unsharp · median · min_filter · max_filter
smoothing)gaussian · mean_box · bilateral · unsharp · sk_tv · sk_wavelet · sk_rolling_ball · sk_nlm
*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.