select_contours — 2D `contour` op

• Data kinds: contour → contour

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

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

select_contours: 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

Selects XLD contours by filtering on point count (length). Equivalent to HALCON's `select_contours_xld` (Select XLD contours according to several features.).

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

`a が残す最小点数のしきい値を 3〜43（3 + int(40a)）に振る。b` は未使用。輪郭を構成する点の数（≒長さ）がしきい値未満のものを丸ごと捨てる。HALCON 版は点数以外にも円形度・凸性などの特徴で選べるが、この実装は点数のみ。

Detailed usage guide

• gallery2d_contour_measure 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.

threshold 0.50 0.50
sk_find_contours 0.50 0.50
select_contours 0.50 0.50

▸ Load this pipeline · Load & run

Runnable examples (verified samples that actually call this op)

• gallery2d_contour_measure — py -3.11 examples/gallery2d_contour_measure.py

• quickstart — py -3.11 examples/quickstart.py

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

identity · smooth_contours · fit_line_contours · contours_to_region · count_contours · total_length · select_contours_xld · smooth_contours_xld

Same category (`contour`)

smooth_contours · fit_line_contours · contours_to_region · sk_find_contours · edges_sub_pix · lines_gauss · select_contours_xld · smooth_contours_xld

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

select_contours — 2D contour op