rank op• Data kinds: image → image
• Call: fullseye.apply(img, "cv_median", a=0.5, b=0.5) (the 2-D model is one image plus two scalar knobs a,b∈[0,1])
• HALCON equivalent: median_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).*
Median filter (OpenCV implementation). A standard denoising method that replaces each pixel with the median of its square neighborhood (especially effective against salt-and-pepper noise, and relatively edge-preserving).
> The detailed description below is the original text — the summary and the headings are translated.
HALCON の median_image に相当。実装は `cv2.medianBlur(_u8(v), ksize=3+2*int(a*3))` —— a はカーネルサイズを 3, 5, 7, 9(奇数)に振る。b は未使用。8 bit に量子化してから処理するため、元画像の微妙な階調は失われる。sk_median_disk と違い正方形カーネル。
• 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.
cv_median 0.50 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
rank)median · min_filter · max_filter · percentile · sk_median_disk · median_image · median_rect · median_separate
*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.