Face recognition: the good, the bad and the not-so-pretty

Access & Identity Management Handbook 2021 Editor's Choice

As part of our ongoing practical and localised research to compare our preferred vendors’ products against other competing products, Fulcrum Biometrics Southern Africa has imported a number of devices for facial recognition and temperature scanning from different vendors. The bottom line is, beware and dig deeper.

There is a wide range of choices on the market for different biometric recognition methods or ‘modalities’. These vary greatly in the three key things that end users should have a good understanding of: price, accuracy, and user experience or convenience. Yes, there are biometric fits for varying purposes and it is vital you understand the needs of your application, especially factors such as accuracy when time-and-attendance (T&A) clocking has financial implications.

Firstly, while vendors seem to somewhat ‘personalise’ results to suit their particular product, a little research on the Web will reveal that it is widely accepted that face recognition, whilst fast improving, remains the least accurate of the popular modalities – and that’s before you wear a mask or grow a beard.

What you may not know however is that while face recognition is the most un-intrusive, it can be less accurate than the others, to the extent that it may present significant risk and render itself unsuitable for certain applications. Remember that false rejection may just be an inconvenience to the user, but false acceptance is potentially a severe security event.

Southern African outcome

Our research has brought us to the conclusion that substandard equipment was rushed onto the market to take advantage of the COVID-19 pandemic. Pressurised decisions may have been made as a consequence, resulting in some customers having invested unwisely and assuming any device would be fit for their purposes.

Are face recognition algorithms improving?

The global authority on face algorithms in the USA, the National Institute of Standards and Technology (NIST), has released several reports on facial recognition systems and the effect of masks. Whilst these indicate that massive gains in accuracy have been made in recent years with as much as a 20-times improvement, they also show that even the best face algorithms may reduce accuracy by 50% when wearing a mask, and again, beards are another story. Please note that these test results are related to pre COVID-19 algorithms. [A release from National Institute of Standards and Technology (NIST) on 1 December 2020 about face recognition with masks, however, noted “some software developers have made demonstrable progress at recognising masked faces” – see more at https://www.nist.gov/news-events/news/2020/12/face-recognition-software-shows-improvement-recognizing-masked-faces, or use the short link: www.securitysa.com/*nist1 – Ed.]


What effect do masks have on accuracy?

A NIST test inspired by the COVID-19 pandemic and the widespread requirement that people wear protective face masks in public places has driven a need to understand how cooperative face recognition technology deals with occluded faces, often with just the periocular area and above visible.

Without masks, the top-performing algorithms usually have error rates of about 0,3%. Nevertheless, when even the most accurate algorithms were confronted with the highest-coverage masks, error rates jumped to about 5%, researchers found.

Some algorithms that are quite competitive with unmasked faces actually fail to authenticate between 20% and 50% of images with masks. “This is noteworthy, given that around 70% of the face area is occluded by the mask,” the report reads. (It should be noted that several vendors have since released ‘mask ready’ algorithms that ‘improve’ performance).

We at Fulcrum SA have experienced these results in the field and, trust us, if you wear a motorcycle bandana or ‘buff’ covering, it will not recognise you at all. Multi-colour masks also have a significant effect on the accuracy.

It is important, however, to recognise that there is a stark difference between the best and worst algorithms, many of the latter having arrived with low-cost terminals into this country. In comparison to the false negative rates under 1% for black females and white males among the highest-performing algorithms, the lowest-performing algorithms had false negatives rates, for blacks and whites, as high as 99%.

It is not feasible from a cost standpoint to have government-grade face algorithms in all facial recognition access control devices. There are devices that strike a good balance between price and performance by utilising top tier algorithms designed for purpose, while keeping costs to a minimum.

Fulcrum in SA uses only the best algorithms in our solutions so you can be assured that performance and accuracy are paramount (see https://www.rankone.io/).

In terms of demographic performance, an algorithm should exhibit minimal impact due to race or gender – a critical factor in Africa is to have higher accuracy scores for dark faces because most algorithms work better with light ones and Rank One excels here.

Temperature measurement is another aspect that warrants comment. Cheap ‘skin surface temperature’ sensors can be highly inaccurate and affected by wind, sunlight and other localised ambient factors. For concerned users, only quality infrared sensors should be used, such as the leading FLIR Lepton enhanced IR micro-sensor that is used in our devices. It is fully contactless and operates at the same stand-off distance as the device itself (see https://www.flir.eu/).

Should I be using a multimodal terminal?

Multimodal biometrics technology has recently gained interest due to its capacity to overcome certain inherent limitations of single biometric modalities and to improve the overall recognition rate performance, whilst retaining convenience and a quality user experience.

The highly accurate iris modality is considered one of the most reliable biometric characteristics; it remains unchanged throughout the adult human life and is much less likely to suffer from accidental damage than palms or fingers. Used in combination with the face modality, which is still the most natural, fast and unobtrusive way to recognise a person, it creates a balance between usability and accuracy. Our devices use a specialised technique of fast face matching with the Rank One algorithm, resorting to iris only if a facial mismatch or low-threshold match occurs. Iris recognition is not affected by the wearing of any type of mask, beards, makeup or facial tattoos.

Simplifying integration

For those seeking to seamlessly integrate into their back-end systems, our Fulcrum Biometric Framework (FbF) and a comprehensive SDK provide you with a complete turnkey access control and time-and-attendance solution for your business. Built upon more than 15 years of experience enabling biometric solutions, FbF is a suite of tools that simplify the inclusion of biometrics into any new or existing mobile, desktop, or web-based application. With FbF tools, you have everything you need to biometrically link a physical person to their records in your database or application. By choosing to work with the FbF tools instead of low-level SDKs, your time can be spent focused on perfecting your application or solution’s features, rather than becoming an expert in implementing biometrics

This article is a shortened version of the full paper by Dave Crawshay-Hall, which can be downloaded at www.securitysa.com/*fulcrum1.


Credit(s)




Share this article:
Share via emailShare via LinkedInPrint this page



Further reading:

FortiGuard labs reports disruptive shift of cyber threats
Issue 1 2021 , Editor's Choice
Threat intelligence from the second half of 2020 demonstrates an unprecedented cyber-threat landscape where cyber adversaries maximised the constantly expanding attack surface to scale threat efforts around the world. Adversaries proved to be highly adaptable, creating waves of disruptive and sophisticated attacks.

Read more...
The year resilience paid off
Issue 8 2020 , Editor's Choice, Security Services & Risk Management
Hi-Tech Security Solutions spoke to Michael Davies about business continuity and resilience in a year when everything was put to the test.

Read more...
Retail solutions beyond security
Issue 8 2020, Axis Communications SA, Technews Publishing, Hikvision South Africa , Editor's Choice, CCTV, Surveillance & Remote Monitoring
The need for security technology to deliver more than videos of people falling or stealing from retail stores is greater than ever.

Read more...
Smart healthcare
Issue 2 2021 , Editor's Choice
In the past year, hospitals, elder care and other healthcare facilities have found themselves overwhelmed with new patients, COVID-19 regulations and other side effects of the pandemic. As efforts focused ...

Read more...
Platform-based access management solution
Issue 2 2021, ASSA ABLOY South Africa , Editor's Choice
Available in South Africa and throughout sub-Saharan Africa, new Incedo Business connects all your security software and hardware within one platform. You can easily scale it up or down, based on your needs, to keep your people moving and your business growing.

Read more...
FS Systems celebrates 50 years
Issue 2 2021 , Editor's Choice
This year, FS Systems celebrates 50 years in the fire detection and enterprise security market, successfully executing projects in over nine countries in Africa and LATAM.

Read more...
Formative AI and distributed cloud among four megatrends revealed at MIPS 2021
Issue 2 2021, Milestone Systems , Editor's Choice
Almost 4000 participants representing end customers, technology partners and media from across the globe attended the first virtual MIPS conference, held over two days in March 2021.

Read more...
Kiss passwords G00dby3
Issue 2 2021 , Editor's Choice
Cisco Secure has unveiled infrastructure agnostic, passwordless authentication by Duo which enables enterprise users to skip the password and securely log into cloud applications via security keys or biometrics built into modern laptops and smartphones.

Read more...
200 000 daily access transactions
Issue 2 2021, Impro Technologies , Editor's Choice
The University of KwaZulu-Natal’s legacy access control system was suffering from increasingly limited support, both in terms of hardware and software, with maintenance becoming a pressing concern as it on-boards approximately 9000 new students each year across five campuses.

Read more...
Do not take the bait
Issue 2 2021 , Editor's Choice
Banks are unable to fully protect consumers from falling prey to the tactics used by fraudsters to obtain confidential information such as banking details, card information and one-time-pins.

Read more...