halcon_ext op• Data kinds: image → image
• Call: fullseye.apply(img, "hx_close_edges", 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 (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: knob a sweep (docs site)
Sweeping knob b (0.1 / 0.5 / 0.9, the other knob at its default):
▸ hx_close_edges: 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: 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 the gaps in an edge-amplitude image: threshold at a, then morphological closing (radius b).
> The detailed description below is the original text — the summary and the headings are translated.
`v > a で二値化した後、scipy.ndimage.binary_closing を 3×3 全結合(8 近傍)構造要素の it` 回反復
= `(2*it+1)` 角の正方形で 1 回クロージング(膨張→収縮)し、0/1 の float 画像で返す。
• `a` → 二値化しきい値(エッジ振幅画像を想定。a=0 では 0 より大きい画素がすべて前景)。
• `b → 構造要素の反復回数 it = 1 + int(b*3)`(1〜4、正方形の辺は 3〜9 画素)。閉じられる隙間はおおむね
`2*it` 画素以下。
注意: `binary_closing は画像外を 0 として収縮するため、画像端から it` 画素の帯は必ず 0 になる
(全面 1 の 20×20 に it=1 を掛けると残るのは 18×18)。端に接するエッジを扱うときは前に余白を付けるか、結果を
膨張し直す。入力は image(エッジ振幅)で出力も image sort だが中身は二値。`hx_nonmax_dir や sobel_amp` の
後に置き、つながったエッジは `hx_region_to_label や hx_detect_edge_segments` へ渡す。
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 0.50 0.50
▸ Load this pipeline · Load & run
• gallery2d_halcon_ext — py -3.11 examples/gallery2d_halcon_ext.py
• poc_metal_grain_size — py -3.11 examples/poc_metal_grain_size.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.