halcon_ext op• Data kinds: image → image
• Call: fullseye.apply(img, "hx_close_edges_length", a=0.5, b=0.5) (the 2-D model is one image plus two scalar knobs a,b∈[0,1])
• HALCON equivalent: close_edges_length (the HALCON reference is a useful guide to its meaning and parameters)
*The figure is the actual output on a synthetic 128×128 input. Left: input, right: output. Point clouds are drawn as a top-down scatter (brightness = z), 1-D series as a line plot, volumes as the maximum-intensity projection along z, videos as the middle frame, complex images as magnitude; return values that are not pictures are shown as the values themselves.*
Sweeping knob a (0.1 / 0.5 / 0.9, the other knob at its default):
▸ hx_close_edges_length: knob a sweep (docs site)
Sweeping knob b (0.1 / 0.5 / 0.9, the other knob at its default):
▸ hx_close_edges_length: knob b sweep (docs site)
On other images (synthetic scene / photo / coins. Top row: inputs, bottom row: their outputs. Knobs at default):
▸ hx_close_edges_length: other inputs (docs site)
*The 4th column is a colour (H,W,3) input. This op handles colour without crossing channels (it does not convolve the colour channel as a third spatial axis).*
close_edges, and additionally drop short edge fragments below a length (in pixels) threshold.
> The detailed description below is the original text — the summary and the headings are translated.
`v > a で二値化 → 3×3(8 近傍)構造要素で 1 回 binary_closing → ndimage.label`(既定の 4 近傍連結)で
連結成分にし、画素数が `min_len` 未満の成分を落として 0/1 の float 画像で返す。
• `a` → 二値化しきい値。
• `b → 残す最小画素数 min_len = 2 + int(b*20)`(2〜22)。
• 成分が 1 つも無ければクロージング結果をそのまま返す。
注意: クロージングの構造要素は固定 3×3 で、`hx_close_edges` のような幅の調整は無い。ラベリングが 4 近傍のため
斜めにつながる 1 画素幅の線は別成分に分かれ、「長さ」が短く数えられて消えやすい。`binary_closing` は画像外を
0 と扱うので端 1 画素の帯は常に 0 になる。「長さ」は成分の画素数であり幾何学的な線長ではない(塊も長いと数える)。
Blank frame (measured): feeding an image of uniform brightness gives an empty result — every pixel is background (0) — regardless of the brightness. Pure white and pure black behave alike; brightness by itself detects nothing.
• gallery2d_halcon_ext 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.
hx_close_edges_length 0.50 0.50
▸ Load this pipeline · Load & run
• gallery2d_halcon_ext — py -3.11 examples/gallery2d_halcon_ext.py
image as input)identity · gaussian · mean_box · bilateral · unsharp · median · min_filter · max_filter
halcon_ext)hx_gen_circle · hx_gen_ellipse · hx_gen_rectangle2 · hx_gen_checker_region · hx_gen_grid_region · hx_gabor · hx_fit_surface1 · hx_fit_surface2
*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.