Description
Return visible fraction after accounting for excluded border.
Biometric research records separate subject IDs, template dimensions, image geometry, enrollment support and attempt budgets. Local counts and comparisons can reveal inconsistencies without reading biometric templates, detecting a physical trait or authenticating a person’s identity.
Return visible fraction after accounting for excluded border.
When to use this tool
Use Biometric Mask Occluded Area Share when checking the stated biometric record, count, support, geometry or budget convention.
How to use the tool and how it works
- Enter imageArea, occludedArea, excludedBorder, borderOverlap. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read eligibleArea, eligibleOccluded, visibleFraction. Use the output convention below.
Return visible fraction after accounting for excluded border. Require a positive eligible image area and valid overlap counts; eligibleOccluded = occludedArea-borderOverlap, visibleFraction = 1-eligibleOccluded/(imageArea-excludedBorder).1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| imageArea | Image Area | Required. Finite number. |
| occludedArea | Occluded Area | Required. Finite number; minimum 0. |
| excludedBorder | Excluded Border | Required. Finite number; minimum 0. |
| borderOverlap | Border Overlap | Required. Finite number; minimum 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| eligibleArea | Eligible Area | Required. Finite number. |
| eligibleOccluded | Eligible Occluded | Required. Finite number. |
| visibleFraction | Visible Fraction | Required. Finite number. |
{
"input": {
"imageArea": 100,
"occludedArea": 30,
"excludedBorder": 10,
"borderOverlap": 5
},
"output": {
"eligibleArea": 90,
"eligibleOccluded": 25,
"visibleFraction": 0.7222222222222222
}
}Limitations and assumptions
- Areas are supplied rather than measured from an image; visible fraction alone does not establish capture quality or matching performance.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Use verified acquisition/enrollment records and the complete appropriate format and evaluation process for actual identity, quality, capacity or privacy decisions.
References
Similar or alternative tools
- Fingerprint Image Ridge Spacing Factor
Return ridge spacing and its reciprocal density.
- Biometric Failure Acquisition Share Tool
Calculate biometric failure acquisition share from explicit caller-supplied inputs.