Ethnicity and Biometric Uniqueness: Iris Pattern Individuality in a West African Database

TL;DR

This study analyzes iris pattern uniqueness in a West African population, demonstrating that despite ethnic differences, individual identification remains robust with appropriate threshold adjustments.

Contribution

It introduces the AFHIRIS database and shows that iris discrimination performance is resilient across ethnic groups with minor threshold tuning.

Findings

Reduced entropy in African iris patterns due to coarser features

Stochastic models accurately fit empirical distributions

Minor threshold adjustments maintain discrimination performance

Abstract

We conducted more than 1.3 million comparisons of iris patterns encoded from images collected at two Nigerian universities, which constitute the newly available African Human Iris (AFHIRIS) database. The purpose was to discover whether ethnic differences in iris structure and appearance such as the textural feature size, as contrasted with an all-Chinese image database or an American database in which only 1.53% were of African-American heritage, made a material difference for iris discrimination. We measured a reduction in entropy for the AFHIRIS database due to the coarser iris features created by the thick anterior layer of melanocytes, and we found stochastic parameters that accurately model the relevant empirical distributions. Quantile-Quantile analysis revealed that a very small change in operational decision thresholds for the African database would compensate for the reduced entropy and generate the same performance in terms of resistance to False Matches. We conclude that despite demographic difference, individuality can be robustly discerned by comparison of iris patterns in this West African population.