wiring op• Data kinds: labels2d × labels2d × table → table
• Call: import fullseye as fs; fs.ledger.seg_wiring_variation(a, b, synapses, spacing=None, background=0) (to call the implementation directly, import segcompare; segcompare.seg_wiring_variation(a, b, synapses, spacing=None, background=0); from the registry, opsemproof.get("seg_wiring_variation"))
How a candidate segmentation `b corrupts the wiring diagram of truth a`, in bits.
Two levels, both VOI split / merge (`synapses as in :func:seg_synapse_partners`):
• synapse ends (`split / merge, voi`): the segmentation VOI measured only
at the `2n synapse ends instead of every pixel. split` = two ends on one true
neuron now on different objects (the neuron was cut between its synapses); `merge`
= ends on different true neurons now on one object (they were glued). Cutting a
neuron whose `s ends divide s1 / s2 raises split` by exactly
`(s / 2n)·H2(s1 / s)`. Pixels far from any synapse cost nothing here.
• connections (`connection_split / connection_merge`): synapses grouped by
their (pre object, post object) pair — one true connection scattered over several,
or different true connections fused into one (synapses attributed to the wrong
partner). A connection with a single synapse cannot scatter, so this level is blind
to cuts that only rename a one-synapse connection; the ends level is not.
Provenance: the ends level is the "synapse VI" of Plaza, Scheffer & Chklovskii 2014
(*Focused proofreading*, arXiv:1409.1199; VI over the voxels carrying synaptic
annotations, implemented in NeuroProof, C++). The connection level, the lost-synapse
convention and the per-edit closed forms (`(s/2n)·H2(s1/s)` for a cut) are this module's. Synapses with an end on
`background` in the truth are dropped; in the candidate, each such synapse is lost
and counted in `n_lost` as its own singleton at both levels (not one shared
"background" object, which would fake a huge merge). Also returns `split_connections` (true connections
spread over 2+ candidate ones), `merged_connections` (candidate connections holding
synapses of 2+ true ones), `edges_a / edges_b and n` (synapses scored).
Raises `ValueError: as :func:seg_synapse_partners; shapes of a and b`
differ; no synapse left after dropping background in the truth.
• 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.
• poc_em_wiring_errors — py -3.11 examples/poc_em_wiring_errors.py
table as input)seg_synapse_partners · seg_synapse_nri · seg_wiring_exposure
wiring)seg_synapse_partners · seg_synapse_nri · seg_wiring_exposure
*Provenance: segcompare.py — EMPROOF 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.