m1_measure_thresh — 2D `measure1d` op

• Data kinds: image → feature

• Call: fullseye.apply(img, "m1_measure_thresh", a=0.5, b=0.5) (the 2-D model is one image plus two scalar knobs a,b∈[0,1])

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

m1_measure_thresh: 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

Counts how many times the brightness profile crosses a specified level along a caliper line through the centre (equivalent to HALCON `measure_thresh`: extracts points with a specific gray value along a rectangle/arc).

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

`a は線の向き（theta = a*pi）、b` はグレー値のしきい値レベル（0〜1、そのまま）。生のプロファイル（平滑化なし）がこのレベルをまたぐ回数を feature（整数値）として返す。線が画像に掛からない場合は 0.0。

Detailed usage guide

• gallery2d_contour_measure family guide

Background guides (the physics and conventions behind this op)

• measurement_uncertainty — 計測の不確かさと校正の知識 — 「測れている」を主張するために

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.

m1_measure_thresh 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

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

identity

Same category (`measure1d`)

m1_measure_projection · m1_measure_pos · m1_measure_pairs · m1_fuzzy_measure_pos

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

m1_measure_thresh — 2D measure1d op