At Bredemarket, I work with a number of companies that provide biometric systems. And I’ve seen a lot of other systems over the years, including fingerprint, face, DNA, and other systems.
The components of a biometric system
While biometric systems may seem complex, the concept is simple. Years ago, I knew a guy who asserted that a biometric system only needs to contain two elements:
- An algorithm that takes a biometric sample, such as a fingerprint image, and converts it into a biometric template.
- An algorithm that can take these biometric templates and match them against each other.
If you have these two algorithms, my friend stated that you had everything you need for an biometric system.
Well, maybe not everything.
Today, I can think of a few other things that might be essential, or at least highly recommended. Here they are:
- An algorithm that can measure the quality of a biometric sample. In some cases, the quality of the sample may be important in determining how reliable matching results may be.
- For fingerprints, an algorithm that can classify the prints. Forensic examiners routinely classify prints as arches, whorls, loops, or variants of these three, and classifications can sometimes be helpful in the matching process.
- For some biometric samples, utilities to manage the compression and decompression of the biometric images. Such images can be huge, and if they can be compressed by a reliable compression methodology, then processing and transmission speeds can be improved.
- A utility to manage the way in which the biometric data is accessed. To ensure that biometric systems can talk to each other, there are a number of related interchange standards that govern how the biometric information can be read, written, edited, and manipulated.
- For fingerprints, a utility to segment the fingerprints, in cases where multiple fingerprints can be found in the same image.
So based upon the two lists above, there are seven different algorithms/utilities that could be combined to form an automated fingerprint identification system, and I could probably come up with an eighth one if I really felt like it.
My friend knew about this stuff, because he had worked for several different firms that produced fingerprint identification systems. These firms spent a lot of money hiring many engineers and researchers to create all of these algorithms/utilities and sell them to customers.
How to get these biometric system components for free
But what if I told you that all of these firms were wasting their time?
And if I told you that since 2007, you could get source code for ALL of these algorithms and utilities for FREE?
Well, it’s true.
To further its testing work, the National Institute of Standards and Technology (NIST) created the NIST Biometric Image Software (NBIS), which currently has eight algorithms/utilities. (The eighth one, not mentioned above, is a spectral validation/verification metric for fingerprint images.) Some of these algorithms and utilities are available separately or in other utilities: anyone can (and is encouraged to) use the quality algorithm, called NFIQ, and the minutiae detector MINDTCT is used within the FBI’s Universal Latent Workstation (ULW).
As I write this, NBIS has not been updated in six years, when Release 5.0.0 came out.
Is anyone using this in a production system?
And no, I am unaware of any law enforcement agency or any other entity that has actually USED NBIS in a production system, outside of the testing realm, with the exception of limited use of selected utilities as noted above. Although Dev Technology Group has compiled NBIS on the Android platform as an exercise. (Would you like an AFIS on your Samsung phone?)
But it’s interesting to note that the capability is there, so the next time someone says, “Hey, let’s build our own AFIS!” you can direct them to https://www.nist.gov/itl/iad/image-group/products-and-services/image-group-open-source-server-nigos#Releases and let the person download the source code and build it.