NOTICE

This software (or technical data) was produced for the U. S. Government under contract, and is subject to the Rights in Data-General Clause 52.227-14, Alt. IV (DEC 2007) (C) 2023 The MITRE Corporation. All Rights Reserved. Approved for Public Release; Distribution Unlimited. Public Release Case Number 18-0812.

Summary

BIQTIris is a reference library for computing iris image statistics using various quality attributes, features, and ISO metrics. It is part of the open-source BIQT Framework.

Images smaller than 256x256 or larger than 1000x680 are not supported. Raw image data is assumed to have a color depth of 8 bpp.

Features

The following features are reported by this provider:

• image_height value range: [256, +inf) - Image height measured in pixels.
• image_width value range: [256, +inf) - Image width measured in pixels.
• iris_center_x value range: [1, +inf) - The x-coordinate of the iris center in the image.
• iris_center_y value range: [1, +inf) - The y-coordinate of the iris center in the image.
• iris_diameter value range: [224, 432] - Raw diameter of the iris measured in pixels.
• pupil_center_x value range: [1, +inf) - The x-coordinate of the pupil center in the image.
• pupil_center_y value range: [1, +inf) - The y-coordinate of the pupil center in the image.
• pupil_diameter value range: [134, 202] - Raw diameter of the pupil measured in pixels.
• pupil_radius value range: [32, 101] - Raw radius of the pupil measured in pixels.

Quality Metrics

The following quality metrics are reported by this provider:

• contrast value range: [0, +inf) - Raw score quantifying overall image contrast.
• iris_pupil_gs value range: [0, +inf) - Raw measure quantifying how distinguishable the boundary is between the pupil and the iris.
• iris_sclera_gs value range: [0, +inf) - Raw measure quantifying how distinguishable the boundary is between the iris and the sclera.
• pupil_circularity_avg_deviation value range: [0, +inf) - Average deviation for the dimensionless pupil radii at corresponding angle segments.
• quality value range: [0, 100] - An overall quality score that leverages several statistics together.
• sharpness value range: [0, +inf) - Raw score quantifying the sharpness of the image.

NEW! The following ISO metrics are reported by this provider (please refer to ISO/IEC 29794-6:2015 [Information technology — Biometric sample quality — Part 6: Iris image data] documentation for more information):

• iso_overall_quality value range: [0, 100) - The overall ISO quality score based on the product of normalized individual iso metrics.
• iso_greyscale_utilization value range: [0, +inf), recommended value: 6 or greater - The spread of intensity values regarding the pixel values within the iris portion of the image.
• iso_iris_pupil_concentricity value range: [0, 100], recommended value: 90 or greater - The degree to which the pupil centre and the iris centre are in the same location.
• iso_iris_pupil_contrast value range: [0, 100), recommended value: 30 or greater - The image characteristics at the boundary between the iris region and the pupil.
• iso_iris_pupil_ratio value range: (9.58, 121.30), recommended value: between 20 and 70 - The degree to which the pupil is dilated or constricted.
• iso_iris_sclera_contrast value range: [0, 100), recommended value: greater than 5 - The image characteristics at the boundary between the iris region and the sclera.
• iso_margin_adequacy value range: [0, 100], recommended value: greater than 80 - The degree to which the iris portion of the image is centred relative to the edges of the entire image.
• iso_pupil_boundary_circularity value range: [0, 100] - The circularity of the iris-pupil boundary.
• iso_sharpness value range: [0, 100) - The degree of focus present in the image.
• iso_usable_iris_area value range: [0, 100] - The fraction of the iris portion of the image that is not occluded by eyelids, eyelashes, or specular reflections.

The following normalized statistics are also reported by this provider:

• normalized_contrast value range: [0, 1] - Normalized value for contrast.
• normalized_iris_diameter value range: [0, 1] - Normalized value for iris_diameter.
• normalized_iris_pupil_gs value range: [0, 1] - Normalized value for iris_pupil_gs.
• normalized_iris_sclera_gs value range: [0, 1] - Normalized value for iris_sclera_gs.
• normalized_sharpness value range: [0, 1] - Normalized value for sharpness.

NEW! The following ISO normalized statistics are also reported by this provider

• normalized_iso_greyscale_utilization value range: [0, 1] - Normalized value for iso_greyscale_utilization.
• normalized_iso_iris_diameter value range: [0, 1] - Normalized value for iris_diameter.
• normalized_iso_iris_pupil_concentricity value range: [0, 1] - Normalized value for iso_iris_pupil_concentricity.
• normalized_iso_iris_pupil_contrast value range: [0, 1] - Normalized value for iso_iris_pupil_contrast.
• normalized_iso_iris_pupil_ratio value range: [0, 1] - Normalized value for iso_iris_pupil_ratio.
• normalized_iso_iris_sclera_contrast value range: [0, 1] - Normalized value for iso_iris_sclera_contrast.
• normalized_iso_margin_adequacy value range: [0, 1] - Normalized value for iso_margin_adequacy.
• normalized_iso_sharpness value range: [0, 1] - Normalized value for iso_sharpness.
• normalized_iso_usable_iris_area value range: [0, 1] - Normalized value for iso_usable_iris_area.