rank_image — 2D `rank` op

• Data kinds: image → image

• Call: fullseye.apply(img, "rank_image", a=0.5, b=0.5) (the 2-D model is one image plus two scalar knobs a,b∈[0,1])

• HALCON equivalent: rank_image (the HALCON reference is a useful guide to its meaning and parameters)

rank_image: 入力 → 出力

*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).*

Usage

A general-purpose rank filter (`ndimage.percentile_filter) that sorts the pixel values in a window in ascending order and returns the value at the specified percentile position. It is a continuous generalization: percentile 0 corresponds to erosion, 100 to dilation, and 50 to median. Equivalent to HALCON's rank_image` (Compute a rank filter with arbitrary masks.) (HALCON can take an arbitrarily shaped mask, but here it is fixed to a square mask).

> The detailed description below is the original text — the summary and the headings are translated.

`a が窓の一辺を {3,5,7,9} で、b` がパーセンタイルを 5〜95% の

範囲で振る。両方が使われる。

Detailed usage guide

• gallery2d_smoothing_rank family guide

References (sample data, literature)

• 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.

Try it in Studio

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.

rank_image 0.50 0.50

▸ Load this pipeline · Load & run

Runnable examples (verified samples that actually call this op)

• gallery2d_smoothing_rank — py -3.11 examples/gallery2d_smoothing_rank.py

• poc_dehazing — py -3.11 examples/poc_dehazing.py

Ops the type connects to (they accept `image` as input)

identity · gaussian · mean_box · bilateral · unsharp · median · min_filter · max_filter

Same category (`rank`)

median · min_filter · max_filter · percentile · sk_median_disk · cv_median · median_image · median_rect

*Provenance: ops.py — 2D operator registry. This per-op note is generated by tools/opdocs.py md (do not hand-edit).*

rank_image — 2D rank op