Utility: refers to the impact of the individual biometric sample on the overall performance of a biometric system.
Thus, the class separability and the score reliability (dispersion) or separability measures give an indication of the quality of the biometric samples and the matcher [22].
Thus, the class separability and the score separability measures give an indication of the quality of the biometric samples and the matcher.
Generally speaking, if biometric samples are of good quality, matching scores of the genuine and imposters are more easily separable.
In a biometric system, some of the auxiliary information or quality measures [18] that are associated with the biometric samples affect the system's discrimination capabilities, even though they do not provide the capability to identify the subject by themselves.
Also, because the error value calculation is determined based on the mean and variance of each biometric, therefore each user must provide multiple biometric samples to generate the associated means and variances.
"In our view, the … more intrusive powers [such as detention, strip-searching, searching the contents of personal electronic devices, the taking of biometric samples, seizure and retention of property] should be exercisable only if the examining officer reasonably suspects that the person is or has been involved in terrorism".
Several factors that cause different types of degradations of biometric samples, including image features that attribute to the effects of these degradations, are discussed.
Ancillary information includes measures indicating the quality of the acquired biometric samples or certain additional information about the user [11].
Another very important feature for the security and proper working of a biometric system is to assure that the capture of the biometric sample and measurement of liveness occur at the same point in space and time [ 11].
