features op• Data kinds: image → feature
• Call: fullseye.apply(img, "xwt_packet_entropy", a=0.5, b=0.5) (the 2-D model is one image plus two scalar knobs a,b∈[0,1])
*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).*
Energy dispersion of wavelet packets (Shannon entropy). Performs a depth-2 wavelet packet decomposition with `db1, treats the normalized distribution of the energy (sum of squared coefficients) of each of the 16 leaf subbands as a probability distribution, computes its Shannon entropy, and normalizes it to [0,1] by dividing by log2(16)`.
> The detailed description below is the original text — the summary and the headings are translated.
`a, b` は未使用。値が 1 に近いほどエネルギーが全周波数帯に均等に分散(テクスチャが複雑)、0 に近いほど特定の帯域に集中(単純なパターンや平坦な領域)していることを示す。
• gallery2d_features 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.
xwt_packet_entropy 0.50 0.50
▸ Load this pipeline · Load & run
• gallery2d_features — py -3.11 examples/gallery2d_features.py
feature as input)features)blob_count · area_frac · count_contours · total_length · vol_count · sk_euler · sk_entropy_feat · sk_blur_effect
*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.