Calcite | Level 5

how to convert fingerprint image to numeric value

Hi I have a project that I am working on and need to read fingerprint to and store them as unique values. I also need to be able to scan new fingerprint and compare them to exiting values therefore accuracy is key. Is there anyway that SAS could assist me in this.

4 REPLIES 4
Diamond | Level 26

Re: how to convert fingerprint image to numeric value

Bitmaps, pngs and such like are a store of each pixel and its color value.  In theory, if you know the file format, you can read in the file, produce some sort of formula on the read in pixel information, and then store that as a your number.  Personally I would say getting some professional fingerprint software to fully analyse hi res images of the fingerprint would be a better solution, but so long as you know your formula for converting pixels into a given id, it is possible.

Super User

Re: how to convert fingerprint image to numeric value

You would need to code a Fast Fourier Transformation to store the patterns in a way that allows comparisons regardless of size and orientation.

Google 'fft image pattern matching" to get a first impression of what this means. Once you have the algorithm, you might proceeed to find methods for doing this in SAS.

Calcite | Level 5

Re: how to convert fingerprint image to numeric value

I have no idea what that is but I will invest in learning it now. I also
saw that SAS has a FFT function. I looked at the documentation and I was
knocked out by the mathematics. Is do you think that is the right method to
use?

Super User

Re: how to convert fingerprint image to numeric value

@muyco_didie wrote:
I looked at the documentation and I was knocked out by the mathematics.

That's what I wanted to point at. I would go looking for software that does this on its own, and see how one could use the reference keys that are generated for the fingerprints in SAS.

Disclaimer: I once (early 1990's) worked for a company who was engaged in this kind of processing. Back then, that meant custom-built circuit boards where the transformation engine was partially hard-wired into a set of high-speed multiplicator and accumulator chips. Today, such things are mostly done by using the processors in GPU chips.

But I had (and still have) no clue how the math worked, that was done by the MSc who held the patent for the process. I only did the routing of the PCB's.

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