hx_estimate_al_am — 2D `halcon_ext` op

• Data kinds: image → feature

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

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

hx_estimate_al_am: input → output

*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.*

*Knob a does not change the output (measured: identical at 0.1 / 0.5 / 0.9).*

*Knob b does not change the output (measured: identical at 0.1 / 0.5 / 0.9).*

Usage

Estimate albedo (reflectance) and ambient light: albedo ~ the luminance range; this op returns the albedo.

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

画像の最大値と最小値の差 `max(v) - min(v) を [0,1] に clip した np.float64` を返す。

「反射率(albedo)が高いほど陰影の明暗差が大きい」という関係を、輝度のダイナミックレンジで代用した推定。

ambient(環境光)は計算せず返さない。

• `a, b` は未使用。

最大・最小の 2 画素だけで決まるため、飽和画素や暗点が 1 つでもあれば 1 に張り付く。雑音に弱いので前段で

`hx_mean_shape や median_rect` を掛ける。min-max 正規化済みの画像では常に 1 になり意味を持たない。

slant の推定 `hx_estimate_sl_al_lr` は反射率 1 を仮定しており、この値で割って補正する用途が想定される。

Detailed usage guide

• gallery2d_halcon_ext 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.

hx_estimate_al_am 0.50 0.50

▸ Load this pipeline · Load & run

Runnable examples (verified samples that actually call this op)

• gallery2d_halcon_ext — py -3.11 examples/gallery2d_halcon_ext.py

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

identity · feature_to_img

Same category (`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).*

hx_estimate_al_am — 2D halcon_ext op