halcon_ext op• Data kinds: image → feature
• Call: fullseye.apply(img, "hx_cooc_feature", a=0.5, b=0.5) (the 2-D model is one image plus two scalar knobs a,b∈[0,1])
• HALCON equivalent: cooc_feature_image (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_cooc_feature: knob a sweep (docs site)
Sweeping knob b (0.1 / 0.5 / 0.9, the other knob at its default):
▸ hx_cooc_feature: knob b sweep (docs site)
Quantise, build the horizontal co-occurrence matrix at distance d, and return the Haralick contrast (a = distance, b selects the angle).
> The detailed description below is the original text — the summary and the headings are translated.
入力 `v([0,1] 画像)を int(v*8) で 8 階調に量子化し(clip で 0〜7)、距離 d` だけ離れた画素対の
出現回数を 8×8 の共起行列にして転置を足し(対称化)、総和で割って確率にする。返すのは Haralick の
contrast `sum p(i,j)*(i-j)^2 を最大値 (8-1)^2 = 49 で割った np.float64`(値域 [0,1])。
• `a → 距離 d = 1 + int(a*3)`(1〜4 画素)。
• `b → 方向。b < 0.5 で水平(同じ行で d 列右)、b >= 0.5 で垂直(同じ列で d` 行下)。斜め方向は無い。
• 画像の幅(または高さ)が `d` 以下で画素対が 1 つも作れないと総和 0 とみなして 0.0 を返す(例外は出さない)。
値が大きいほど隣接画素の階調差が大きい(粗い/コントラストの高いテクスチャ)。8 階調のため微妙な濃淡差は同じ
階調に潰れる。16 階調の `skimage 実装 cooc_feature_matrix` とは階調数・正規化が異なり数値は一致しない。
前段に `hx_gabor や mean_image` など画像 op、後段は feature として比較・しきい値に使う。
• 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_cooc_feature 0.50 0.50
▸ Load this pipeline · Load & run
• gallery2d_halcon_ext — py -3.11 examples/gallery2d_halcon_ext.py
feature as input)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.