vol_edge_probe — 3D probe op

Data kinds: voxeltable

Call: import fullseye as fs; fs.ledger.vol_edge_probe(vol, p0, p1, sigma=1.0, threshold=0.1, spacing=None, polarity='all') (to call the implementation directly, import volprobe; volprobe.vol_edge_probe(vol, p0, p1, sigma=1.0, threshold=0.1, spacing=None, polarity='all'); from the registry, ops3d.get("vol_edge_probe"))

Usage

Sub-sample edges along the probe `p0 -> p1`.

The profile (default sampling of :func:vol_profile_line) is smoothed

with a 1-D Gaussian of `sigma` samples, differentiated with respect

to the physical abscissa `t_mm`, and local extrema of the derivative

magnitude are taken as edges. Each is refined to sub-sample precision by a

3-point parabolic fit; plateau twins closer than 1.5 samples are merged.

`threshold` is an absolute derivative amplitude in intensity per

physical distance unit (per mm when `spacing` is given, per voxel

otherwise) — edges with `|d gray / d t| < threshold` at the peak are

discarded. It is *not* relative to the profile's own maximum: choose it

for your data's intensity range and spacing.

`polarity selects "positive"` (rising, dark -> bright along the

probe), `"negative" (falling) or "all"`.

Returns a list of dicts ordered by distance, each::

{"t_mm": physical distance of the edge from p0,

"position": (z, y, x) interpolated voxel coordinate of the edge,

"amplitude": |d gray / d t| at the peak (intensity / distance unit),

"polarity": +1 rising, -1 falling}

Raises `ValueError` on the same malformed inputs as

:func:vol_profile_line, a negative / non-finite `sigma` or

`threshold, or an unknown polarity`.

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)

wall_thickness_probepy -3.11 examples_3d/wall_thickness_probe.py

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

fuse_to_voxel · mesh_select_lod

Same category (probe)

vol_profile_line · vol_wall_thickness


*Provenance: volprobe.py — 3D 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.