Equalized image

Equalized image, a part of algorithm transparency, is computed from scaled image during feature extraction. Every primary block is equalized separately using data from smoothed histogram to produce high-contrast image. Equalized image is used to compute pixelwise orientation. It is later processed using parallel smoothing and orthogonal smoothing.

Visualization

The following fingerprint image can be reconstructed from this stage's binary data. Visualization itself is not part of transparency data.

Format

Equalized image has the same format as decoded image except that pixels are in range from -1 (white) to 1 (black). Areas outside the mask are set to -1.

Example: 012-equalized-image.cbor

{
  "width": 388,
  "height": 374,
  "cells": [
    -1.0,
    -1.0,
    "... skipped 145,108 items in range -1.00 to 0.998 ...",
    -1.0,
    -1.0
  ]
}