Biometric features and stored templates must be cancellable. In biometrics, feature cancelability refers to the capability to add to each of the stored templates an extra set of information that masks the direct feature representation of the biometric trait. This way, by changing that extra information, stored templates can be cancelled and can no longer be used for authentication, although the same individual ́s biometric trait can be used. This measure is important to guarantee that subjects that see their templates stolen can still restore a secure biometric authentication.
