Facial recognition technology is incredibly good at recognising individual faces from hundreds and even thousands of known faces. However, it is possible that facial recognition (and even humans!) can incorrectly identify an individual. In facial recognition terminology, an incorrect identification is known as a "false positive".
There are several possible causes of incorrect matches as follows:
The sections below explain how to respond to incorrect matches and more importantly how to avoid them.
If an individual is incorrectly identified when they present to NoahFace, they simply need to press the "Not Me" button:
NoahFace will automatically unlearn the association between their face and the identified user, and the next time they present they will either be correctly identified or asked to re-register.
Alternatively, if an individual reports to an Administrator that they were incorrectly matched (and they did not know to press the "Not Me" button), the Administrator can:
Removing a user's consent will delete:
Once this has been done, the identified user (eg: Sammy in this example), will need to re-register.
There are many steps you can take to minimize the possibility of incorrect matches as follows:
You should mount your iPad so that individuals do not have significant back light when they present to NoahFace. For example, make sure the iPad is not facing a window. If this is not possible, you might consider installing artificial shading or front lighting.
You should set your camera brightness (under Settings/Camera in the NoahFace App) so that the images produced are slightly brighter (or over-exposed) than normal.
You should train your employees to:
Facial recognition will produce far more accurate results if it is matching an individual's face against 100 known faces compared with matching it against 10,000 known faces. So, if you have multiple sites and employees do not travel between those sites, you should either:
You can adjust the following facial recognition settings (under Settings/Facial Recognition in the NoahFace App):
Detection Distance indicates how close an individual needs to be to the screen in order to be recognized. Increasing this to "Very Near" will mean individuals need to stand very close to the iPad to be recognized. This will improve the quality of captured images and therefore reduce the possibility of incorrect matches.
Detection Threshold indicates the level of certainty that the image is a face before it is analysed. Increasing this to "High" or "Very High" will the possibility of incorrect matches, however, it will also make it more likely that individuals need to remove any facial coverings (eg: dark glasses, masks, scarves, etc) to be recognized.
Matching Threshold indicates the level of certainty that the detected face belongs to a known user before declaring a match. Increasing this to "Very High" or "Maximum" will reduce the possibility of incorrect matches.