Root minutiae

SourceAFIS » Algorithm » Transparency » Root minutiae

Roots, a part of algorithm transparency, are pairs of minutiae, one from probe fingerprint and one from candidate fingerprint, where pairing starts. They are picked from minutia lists of both fingerprints by matching edge shapes from candidate fingerprint to shapes stored in edge hash of the probe fingerprint.

Key	MIME	Filename in ZIP
`roots`	`application/cbor`	`045-roots.cbor`

Visualization

Visualization of roots was constructed from this stage's CBOR data and shuffled minutiae (for probe and candidate) with original fingerprint images in the background (for probe and candidate). Visualization itself is not part of transparency data.

Probe and candidate fingerprints with pairs of root minutiae connected — Probe fingerprint is left, candidate is right. Green lines connect pairs of minutiae where pairing is attempted.

Format

Root list is a CBOR-encoded list of root pair structures containing fields:

probe - Offset of root minutia in the probe template.
candidate - Offset of root minutia in the candidate template.

Example: 045-roots.cbor

[
  {
    "probe": 31,
    "candidate": 2
  },
  {
    "probe": 39,
    "candidate": 2
  },
  "... skipped 56 items ...",
  {
    "probe": 21,
    "candidate": 4
  },
  {
    "probe": 35,
    "candidate": 4
  }
]