filter_by_volume — 3D `regionprops` op

• Data kinds: voxel → voxel

• Call: import fullseye as fs; fs.ledger.filter_by_volume(vol, min_voxels: 'int', connectivity: 'int' = 26) -> 'np.ndarray' (to call the implementation directly, import regionprops3d; regionprops3d.filter_by_volume(vol, min_voxels: 'int', connectivity: 'int' = 26) -> 'np.ndarray'; from the registry, ops3d.get("filter_by_volume"))

Usage

Return a bool mask with the connected components below min_voxels removed.

Parameters

vol : array_like

3D array of bool or 0/1.

min_voxels : int

Drops components "below" this threshold (< min_voxels). Those "at or above" the threshold are kept.

connectivity : int

6 / 18 / 26.

Returns

ndarray(bool)

True only for components that satisfy the condition. All False if there is no foreground or all components are removed.

Notes:

• min_voxels is rounded with int() before comparison. If it is 1 or less, all components remain.

• Internally label_components → bincount → keeps labels with counts >= min_voxels. Labels are not renumbered and only a bool mask is returned, so if you need numbers pass the result through label_components again.

• The input is converted to bool with everything other than 0 as foreground (NaN is foreground too). Axis order (z, y, x).

• Raises ValueError: input that is not 3-dimensional, connectivity other than 6/18/26.

• Voxel counts are not spacing-corrected, so to threshold in physical units divide by the voxel volume before passing it in.

Background guides (the physics and conventions behind this op)

• measurement_uncertainty — Measurement uncertainty and calibration — what it takes to claim you are measuring

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.

Runnable examples (verified samples that actually call this op)

• region_props_3d — py -3.11 examples_3d/region_props_3d.py

Ops the type connects to (they accept `voxel` as input)

voxel_to_mips · voxel_to_mesh · signed_distance_field · to_points · sobel3d · hessian3d · curvature_maps · edt_jfa

Same category (`regionprops`)

label_components · region_props · largest_component · inner_box3 · vol_label · vol_region_props

*Provenance: regionprops3d.py — 3D operator registry. This per-op note is generated by tools/opdocs.py md (do not hand-edit).*

filter_by_volume — 3D regionprops op