blob_overlay — BLOB extract op

• Data kinds: image2d × labels2d → rgb

• Call: import fullseye as fs; fs.ledger.blob_overlay(image: 'Any', labels: 'Any', alpha: 'float' = 0.5, seed: 'int' = 0) -> 'np.ndarray' (to call the implementation directly, import blob2d; blob2d.blob_overlay(image: 'Any', labels: 'Any', alpha: 'float' = 0.5, seed: 'int' = 0) -> 'np.ndarray'; from the registry, opsblob.get("blob_overlay"))

Usage

Overlays the objects in different colors on the original image and returns a float RGB of shape (H, W, 3).

The exit of this family. It exists so this does not become a type you can build and measure but not look at. Colours follow the same rule as fullseye.colorize_labels; the background stays as the original image.

Detailed usage guide

• blob_analysis 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.

Runnable examples (verified samples that actually call this op)

• poc_bump_coplanarity — py -3.11 examples/poc_bump_coplanarity.py

• poc_fresco_craquelure — py -3.11 examples/poc_fresco_craquelure.py

• poc_gear_tooth_metrology — py -3.11 examples/poc_gear_tooth_metrology.py

• poc_leaf_disease_area — py -3.11 examples/poc_leaf_disease_area.py

• poc_metal_grain_size — py -3.11 examples/poc_metal_grain_size.py

• poc_nuclei_ploidy — py -3.11 examples/poc_nuclei_ploidy.py

• poc_particle_sizing — py -3.11 examples/poc_particle_sizing.py

• poc_powder_grinding_ae — py -3.11 examples/poc_powder_grinding_ae.py

• poc_weld_radiograph_porosity — py -3.11 examples/poc_weld_radiograph_porosity.py

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

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Same category (extract)

blob_region · blob_boundaries

*Provenance: blob2d.py — BLOB 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.