xsp_hilbert_env — 2D texture op

Data kinds: imageimage

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

xsp_hilbert_env: 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

Extracts the amplitude envelope of the analytic signal (Hilbert transform) along the row direction.

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

画素値を [-0.5, 0.5] に平行移動してから各行に 1 次元ヒルベルト変換

(`scipy.signal.hilbert`)を掛け、複素解析信号の絶対値(瞬時振幅)を

正規化して返す。`a, b` は未使用。周期的な縞模様やテクスチャの

「包絡線」を強調するのに向き、位相情報は捨てて振幅だけを残す。列方向

には掛からないため、結果は水平方向の変化にのみ反応する。

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.

xsp_hilbert_env 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.