Anyone with a smartphone that uses facial recognition will know it does not really work with a mask on.
That can be frustrating – but although masks have undoubtedly thwarted the facial-recognition industry, the technology has also adapted. It may sound strange but wearing a mask does not necessarily stop a computer from identifying someone. And there are even examples of the pandemic being used as an excuse to use facial recognition.
Last year, as people began to increasingly wear masks around the world, the prevailing view was it represented a huge challenge to facial recognition. It seemed obvious – algorithms designed to analyse faces would be less accurate if part of the face was concealed.
The National Institute of Standards and Technology (NIST) tested 89 commercial facial-recognition algorithms – and found a 5-50% error rate in matching faces with digitally applied masks to photos of the same person.
But some facial-recognition technologies still work pretty well on those wearing a mask. In January, a US Department of Homeland Security “controlled-scenario test” found one with a 96% success rate – although the results “varied greatly between systems”.
“Based on these results” the department said, “organisations that need to perform photo ID checks could potentially allow individuals to keep their masks on, thereby reducing the risk of Covid-19 infection.” And although some police forces are using facial recognition less – London’s Metropolitan Police, for example, has not conducted a facial-recognition test for over a year – it is still being used, even, reportedly, at Black Lives Matter protests last summer.