Relative contrast mask

SourceAFIS » Algorithm » Transparency » Relative contrast mask

Relative contrast mask, a part of algorithm transparency, is a set of primary blocks where contrast is too low relative to other parts of the image. It is computed during feature extraction. Relative contrast mask contributes to combined mask.

Key	MIME	Filename in ZIP
`relative-contrast-mask`	`application/cbor`	`009-relative-contrast-mask.cbor`

Visualization

Relative contrast visualization can be computed from this stage's binary data mapped onto blocks and the original fingerprint image. Visualization itself is not part of transparency data.

Relative contrast mask visualized as yellow masked out area around fingerprint image — Relative contrast mask. Yellow area consists of blocks excluded due to low contrast.

Format

Relative contrast mask has the same format as absolute contrast mask.

Example: 009-relative-contrast-mask.cbor

{
  "width": 26,
  "height": 25,
  "cells": [
    true,
    true,
    "... skipped 646 items ...",
    true,
    true
  ]
}