quasi_flat_zones — SEGMENTATION graph op

• Data kinds: image2d → table

• Call: import fullseye as fs; fs.ledger.quasi_flat_zones(image, alpha: 'float' = 0.05, *, connectivity: 'int' = 4) -> 'Dict[str, object]' (to call the implementation directly, import seggraph; seggraph.quasi_flat_zones(image, alpha: 'float' = 0.05, *, connectivity: 'int' = 4) -> 'Dict[str, object]'; from the registry, opssegmentation.get("quasi_flat_zones"))

Usage

α-quasi-flat zones (Soille 2008): the connected components joined only by neighbour edges with |f_p − f_q| ≤ α. Returns: `labels (1..k), n_zones` (quasi_flat_zones).

Detailed usage guide

• halcon_segmentation family guide

Background guides (the physics and conventions behind this op)

• graph_hierarchy_and_thresholds — グラフ・階層・閾値の定理でつくる分割 — 何が厳密で、どこで割れ方が倒れるか

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

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

class_ndim_norm

Same category (graph)

graph_cut_binary · alpha_expansion · statistical_region_merging · max_tree · area_opening_attr · alpha_tree · hierarchical_watershed · ultrametric_contour_map


*Provenance: seggraph.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.