xsk2_hog — 2D texture op

Data kinds: imageimage

Call: fullseye.apply(img, "xsk2_hog", a=0.5, b=0.5) (the 2-D model is one image plus two scalar knobs a,b∈[0,1])

xsk2_hog: 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

A visualization image of HOG (Histogram of Oriented Gradients) features. Calls `skimage.feature.hog with visualize=True` and returns the visualization image (discarding the feature vector itself).

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

a がセル 1 辺のピクセル数(`6 + 2*int(a*3)`、6/8/10/12 の 4 段階)を

振る。方向数は 8、ブロックは 2x2 に固定。b は未使用。出力は最大値で

正規化した勾配方向強度の可視化であり、HOG 特徴ベクトルそのものでは

ない。

Detailed usage guide

gallery2d_texture_freq 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.

xsk2_hog 0.50 0.50

▸ Load this pipeline  ·  Load & run

Runnable examples (verified samples that actually call this op)

gallery2d_texture_freqpy -3.11 examples/gallery2d_texture_freq.py

Ops the type connects to (they accept image as input)

identity · gaussian · mean_box · bilateral · unsharp · median · min_filter · max_filter

Same category (texture)

std_filter · gabor · sk_frangi · sk_meijering · sk_hessian · sk_gabor · sk_lbp · sk_entropy


*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.