sk_hysteresis — 2D `segmentation` op

• Data kinds: image → region

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

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

sk_hysteresis: 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

Hysteresis thresholding. Uses two threshold levels: pixels above the higher one are confirmed first, then pixels above the lower one that are connected to a confirmed pixel are also adopted -- the same idea as Canny's edge-linking step, applied to general response images.

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

HALCON の hysteresis_threshold(Perform a hysteresis threshold operation on an image.)に相当。実装は `filters.apply_hysteresis_threshold(v, 0.2+0.3*a, 0.5+0.3*b)` —— a は低い方のしきい値を 0.2〜0.5 に、b は高い方のしきい値を 0.5〜0.8 に振る。a を大きく・b を小さくすると 2 つが逆転しうる(low > high)ので、極端な組み合わせでは skimage 側の挙動に委ねられる点に注意。

Detailed usage guide

• gallery2d_segmentation 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.

sk_hysteresis 0.50 0.50

▸ Load this pipeline · Load & run

Runnable examples (verified samples that actually call this op)

• gallery2d_segmentation — py -3.11 examples/gallery2d_segmentation.py

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

identity · reg_erode · reg_dilate · reg_open · reg_close · fill_holes · select_largest · remove_small

Same category (`segmentation`)

threshold · otsu · canny · adaptive_gauss_thresh · sk_otsu · sk_li · sk_yen · sk_sauvola

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

sk_hysteresis — 2D segmentation op