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Title: On the Efficacy of Correcting for Refractive Effects in Iris Recognition

Abstract

In this study, we aim to determine if iris recognition accuracy might be improved by correcting for the refractive effects of the human eye when the optical axes of the eye and camera are misaligned. We undertake this investigation using an anatomically-approximated, three-dimensional model of the human eye and ray-tracing. We generate synthetic iris imagery from different viewing angles using first a simple pattern of concentric rings on the iris for analysis, and then stone-like texture maps on the iris for experimentation. We estimate the distortion from the concentric-ring iris images and use the results to guide the sampling of xtextured iris images that are distorted by refraction. Using the well-known Gabor filter phase quantization approach, our results indicate that the Hamming distances between iris signatures from different viewing angles can be significantly reduced by accounting for refraction. Over our experimental conditions comprising viewing angles from 0 to 60 degrees, Hamming distances are always reduced, with a median reduction of 7.19% and a maximum reduction of 19.0%.

Authors:
 [1];  [1];  [1];  [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Laboratory Directed Research and Development (LDRD) Program
OSTI Identifier:
962595
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Conference
Resource Relation:
Conference: IEEE Computer Society Conference on Computer Vision and Pattern Recognition, Minneapolis, MN, USA, 20070618, 20070623
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; EYES; PATTERN RECOGNITION; REFRACTION; CORRECTIONS; CAMERAS; ALIGNMENT; iris recognition; biometrics; iris; human eye model; cornea

Citation Formats

Price, Jeffery R, Gee, Timothy Felix, Paquit, Vincent C, and Tobin Jr, Kenneth William. On the Efficacy of Correcting for Refractive Effects in Iris Recognition. United States: N. p., 2007. Web.
Price, Jeffery R, Gee, Timothy Felix, Paquit, Vincent C, & Tobin Jr, Kenneth William. On the Efficacy of Correcting for Refractive Effects in Iris Recognition. United States.
Price, Jeffery R, Gee, Timothy Felix, Paquit, Vincent C, and Tobin Jr, Kenneth William. Mon . "On the Efficacy of Correcting for Refractive Effects in Iris Recognition". United States. doi:.
@article{osti_962595,
title = {On the Efficacy of Correcting for Refractive Effects in Iris Recognition},
author = {Price, Jeffery R and Gee, Timothy Felix and Paquit, Vincent C and Tobin Jr, Kenneth William},
abstractNote = {In this study, we aim to determine if iris recognition accuracy might be improved by correcting for the refractive effects of the human eye when the optical axes of the eye and camera are misaligned. We undertake this investigation using an anatomically-approximated, three-dimensional model of the human eye and ray-tracing. We generate synthetic iris imagery from different viewing angles using first a simple pattern of concentric rings on the iris for analysis, and then stone-like texture maps on the iris for experimentation. We estimate the distortion from the concentric-ring iris images and use the results to guide the sampling of xtextured iris images that are distorted by refraction. Using the well-known Gabor filter phase quantization approach, our results indicate that the Hamming distances between iris signatures from different viewing angles can be significantly reduced by accounting for refraction. Over our experimental conditions comprising viewing angles from 0 to 60 degrees, Hamming distances are always reduced, with a median reduction of 7.19% and a maximum reduction of 19.0%.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}

Conference:
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