world_texture_regions — SEGMENTATION world op

• Data kinds: none → table (an op determined by its arguments alone — it takes no image or data input)

• Call: import fullseye as fs; fs.ledger.world_texture_regions(seed: 'int' = 0, *, size=(192, 192), n_regions: 'int' = 3, mean: 'float' = 0.5, noise: 'float' = 0.03) -> 'Dict[str, object]' (to call the implementation directly, import segworld; segworld.world_texture_regions(seed: 'int' = 0, *, size=(192, 192), n_regions: 'int' = 3, mean: 'float' = 0.5, noise: 'float' = 0.03) -> 'Dict[str, object]'; from the registry, opssegmentation.get("world_texture_regions"))

Usage

World of 2-4 regions that share the same mean but differ only in variance and period (uncuttable by thresholding) (world_texture_regions).

Region = nearest neighbour of well-separated seeds (Voronoi). The patterns, in order: fine noise (σ = noise), coarse noise (σ = 4 noise), stripes (period P₁, orientation θ₁, amplitude 0.2) + noise, stripes (period P₂, orientation θ₂) + noise. All are zero-mean and added to mean (the clip at ±0.45 is symmetric = keeps the mean).

Returns: image, labels, truth = {n_regions, mean, seeds, specs (kind, std (theoretical), period, angle (degrees), amp)}.

Detailed usage guide

• halcon_segmentation family guide

Background guides (the physics and conventions behind this op)

• segmentation_scoring_and_worlds — Scoring segmentations and synthetic worlds with ground truth — which metric is blind to which failure

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.

Runnable examples (verified samples that actually call this op)

• poc_graph_hierarchy_segmentation — py -3.11 examples/poc_graph_hierarchy_segmentation.py

• poc_segmentation_gauntlet — py -3.11 examples/poc_segmentation_gauntlet.py

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

class_ndim_norm

Same category (world)

world_blobs_touching · world_grains_voronoi · world_parts_with_shadow · world_gradient_illumination · world_thin_structures · lens_area · voronoi_cells

*Provenance: segworld.py — SEGMENTATION 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.