Sutability of InSight for Simultaneous
Standards-Compliant Iris and Face
®
Introduction
W
hen compared with competitive iris recognition systems, the AOptix InSight Duo is uniquely well suited to simultaneously capture ISO / ICAO quality face and dual iris images. This advantage is due to a combination of factors
related to the InSight Concept of Operations (or “ConOps”) and standoff distance. The InSight system captures iris images at
a distance of 1.5 to 2.5 meters with a simple instruction set of “Stand at the position marks, look at the system, and open
your eyes.” Therefore, the functionality is already very similar to that which might be expected from a typical ISO / ICAO face
capture system. Synchronous iris and face captures is achieved seamlessly, resulting in a greatly enhanced biometric record
with no additional time or effort.
Key References
This document heavily references ISO / IEC 19794-5:2005: Information technology – Biometric data interchange formats –
Face image data and the associated ISO / IEC 19794-5:2005/Amd 1:2007: Conditions for taking photographs for face image
data. For ease of reading, these standards will be referred to as ISO 19794-5 and ISO 19794-5/Amd 1 for the remainder of
this document. Furthermore, when “ISO / ICAO quality face” imaging is discussed, it is specifically referring to the image
quality requirements set forth in these standards.
Fig. 1 - Actual face image captured by the InSight Duo.
1
Standoff Distance
T
he InSight Duo system captures face and iris images from a distance of 1.5 to 2.5 meters, with a total capture volume of
0.75 cubic meters. At the nominal 2 meter standoff, the capture volume is 1 meter tall, accommodating ADA wheelchair
heights and very tall subjects alike. A representation of the system’s capture volume can be seen in Figure 2.
Impact on Face Imaging
Setting a minimum standoff distance is important for ISO / ICAO quality face imaging to mitigate “fish eye” distortions.
Fish eye distortions occur at short imaging distances as the dimensions of the face become a significant fraction of the
distance from the camera. For instance, the subject’s nose will be closer to the camera than the rest of his face, and will
thus be magnified by its relative proximity to the camera. This type of distortion is undesirable in face recognition. ISO
19794-5 section 7.3.6 specifically states:
“The fish eye … that is associated with unusually large noses in the image is not allowed. While some distortion is almost
always present during portrait photography, that distortion should not be noticeable by human examination.”
ISO 19794-5/Amd 1 includes Annex B – “Conditions for taking photographs for face image data.” Here, various capture
conditions are described and associated with shooting distances, ranging from 0.5 meters to 2.5 meters. While not
explicitly stated in the document, face image distances shorter than 0.5 meters are generally not accepted due to the fish
eye effect.
Fig. 2 - Capture volume of the InSight at a nominal 2-meter distance.
2
Concept of Operations
A
ssociated with floor markings
such as a pair of footprints, the
InSight system has a very simple set of
instructions for subject capture: “Stand on
the position marks, look at the system,
and open your eyes.” From that point
forward, the InSight’s Adaptive Opticsbased closed loop control system takes
over, automatically finding a subject’s face
and capturing iris images in less than 2
seconds for one eye and 4 seconds for
two eyes (See Figure 3). A high-quality
face image is captured simultaneously.
Fig. 3 - The InSight first finds the face and then the eyes.
At the core of the InSight system’s ConOps is the request for subjects to stop briefly and focus intently on the InSight device.
When compared against other “next generation” iris recognition systems that require subjects to walk through a portal in order
to function, this ConOps has several operational advantages related to throughput, FTA rate, and overall matching accuracy (a
matter which is discussed in some depth at http://www.aoptix.com/iris-recognition/advantages/ease-ofuse-conops/insight-vs-on-the-move). The simple instruction set and rapid, effortless image capture are also highly preferable to
“last generation” iris recognition systems that require subjects to position themselves carefully within a very small capture
volume.
Impact on Face Imaging
The streamlined ConOps described here are very much the same as what might be expected for ISO / ICAO quality face
capture. Section B.2.1.1 of ISO 19494-5/Amd 1 states:
“The subject should be instructed to look directly at the camera and keep his or her head erect and shoulders square to the
camera.”
With such a similar instruction set, it is quite feasible to capture both biometric samples at the same time. Furthermore, since
subjects are standing still when imaging with the InSight system, they provide the best opportunity to capture iris images while
not inducing any motion blur, positioning errors, or unnatural poses for the ISO / ICAO quality face capture.
3
Uniqueness of the InSight System
A
s mentioned above, aside from the InSight system, there are generally two types of iris recognition systems
available today: Compact systems with a very small capture volume and short standoff distance, and larger
“on the move” systems that capture iris images from users at standoff distances comparable to the InSight system.
Not only are these systems are more difficult, time consuming, and error prone than the InSight system for iris capture
alone, they are each not suitable for the addition of ISO / ICAO quality face.
Commercially available compact iris capture systems work at a distance of approximately 1 foot (30 cm), well short of
the appropriate distance required for fish eye-free ISO / ICAO quality imaging. Any system that captures iris images
from a person in motion is simply not going to be able to offer the level of illumination and pose control that is required
for ISO / ICAO quality imaging.
In contrast, the InSight Duo system is unique in the industry in that it captures at a distance of 1.5 – 2.5 meters while
asking subjects to do exactly what they would do for a typical passport quality photo. This functionality can allow for
the simultaneous capture of ISO / ICAO quality face and ISO quality irises in about four seconds, using an instruction
set that is simple and intuitive, even for non-acclimated, non-technical subjects who may be separated by a language
barrier and / or literacy issues. Insofar, not only is an InSight-based combined face and iris capture system unique in
its biometric capture capability, but it is also particularly well suited to real world deployments dealing with diverse
international populations.
4
AOptix Technologies, Inc.
695 Campbell TFDIOPMPHZ1BSLXBZt$BNQCFMM$"t1IPOF
www.aoptix.com/iris-recognition
ª