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Fingerprint project

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New Member
I want to make fingerprint authentication based door lock system system. Please suggest which technology should i use to make the scanner and identification algorithm.


New Member
I am making it as major project for final year of BTech... so i dnt need a ready made one. please tell me where to get a scanner circuit from and wht technology should i use to implement identification algorithm


Super Moderator
Well, for starters you should already have a plan of how to proceed, then come to the forum with your already semi-completed project and then ask questions about how to solve the problems you may encounter.


Well-Known Member
How do you plan to solve the problem of acquiring the image of the fingerprint?

How do you plan to solve the problem of comparing the image to existing known fingerprint images?

How do you plan to store known fingerprint image data?

What is your budget?

What is your time frame?

Who are the members of your team, and what are their skill sets? How can you divide the work amongst the team members to ensure that the project can be done on time and within your budget?

What is your initial target platform?

Et cetera. These are all questions you need to answer before you can even start. The answers may change as you go, but you can't just start a major project like this without breaking it down a bit.

What work have you done so far to make this happen?



New Member
1. As we have decided, we want to implement the fingerprint identification algorithm using VI(Virtual Instrumentation). Still we want to know more options because if we get an option which makes the project NOT pc based and still NOT costly, we will prefer it.

2. We do not want to buy a scanner. We want to make a fingerprint scanner on our own. So we want to know which technologies r there to make the same. We are searching a lot but cant find a ckt of the scanner. We shall be grateful if anyone can post the circuit diagram of a fingerprint scanner.


New Member
@ torben
Thank you for reply sir :)
we have decided the things u hv mentioned...
The problem is that we cant find a circuit diagram on net for this project. the only circuit diagram that we have found uses SM630 fingerprint module. this module scans and saves the fingerprints. But we want to make the scanner also on our own. It would be great if we get a circuit diagram of the scanner. Thats the first thing we want to implement.


New Member
Project Guide


Think i can help.

I work as a technical consultant for many companies and one of them is into biometrics: pl visit Legend Systems

Would like to know what all you know about various biometric like iris, Hand Geomerty or finger print etc. various imaging transducers like RF, capacitive, optical etc, various image processing techniques like image enhancement, minutia detection and maching technologies.

I can help after knowing how much you know about biometrics and what you want to do so that i can tell you what you need to know

Best wishes

n.b: I live in Chennai. If you are nearby you can visit our office and interact with our staff who have been working on biometrics for a long time and take their help


New Member
@ Subbu

First of all I thank you for the reply sir!

We could not get help for a standalone fingerprint identification system, so we have decided to make a PC based fingerprint identification system. We have decided to use MATLAB for image processing. We have read various papers which describe the methods of fingerprint identification and what we have found is that minutia extraction is the most reliable approach for the same. So using MATLAB, we want to implement the minutia extracting algorithm.

About MATLAB, we have basic knowledge only, like we know how to implement filters in MATLAB at the most. So we need to understand an already implemented sample code (a small code we have downloaded from internet). And then we will write our own code for the algorithm implementation. But that is not a problem, because i think when we start writing code, we will find solutions to the problems.

About the scanner, we want to buy a fingerprint scanner. But nowhere on internet could we find a scanner that only reads the image and transfer it to computer. All the scanners do more than this. Its a humble request to you to please suggest us which scanner should we buy that only reads the finger and give us the image (capable of connecting directly to computer).

(Only) if there is no such simple scanner available in the market then we are ready to make one. We have learned so far that the optical sensor is the easiest to implement. The touch surface (where finger is placed) is illuminated by phosphor layer. this light when reflected back from finger, strikes the charge coupled device that makes the image of finger. But we need to get the circuit diagram to implement it exactly. Please help us in that if we really need to make a scanner ourselves.

The biggest problem we are facing is that after reading the algorithms and reports of already made projects, we find formulae which we don't understand. I mean, the formulae are written without explanation of what each parameter in it signifies. I am attaching one of the presentations that discusses minutia based identification in which we are facing the same problem. If you go through this ppt, you will get also an idea of how much knowledge do we have about the topic as we have read the ppt and many papers like this.

Please reply and please feel free to ask if i could not give you idea about what kind of help do i need...because we really need somebody to guide us but we have got no encouraging response from anyone till now.


New Member


pls copy and paste this link in url bar and view the ppt. I am not able to upload the file.


New Member
>Its a humble request to you to please suggest us which scanner should we buy that only >reads the finger and give us the image (capable of connecting directly to computer).

Think this may be useful for you.


>The biggest problem we are facing is that after reading the algorithms and reports of >already made projects, we find formulae which we don't understand.

Ok. This requires a good understanding of mathematics particularly trigonometry.
I will try to simplify it and explain to you.
Make a grid of around 400 X 250
make a set of 5 or 6 random points with in the grid
calculate the relative distance between one point to all the other points in vector scale using trigonometry find the distance and the angle.
make another set by shifting the x,y coordinates of the random points by two constants.
calculate the relative distance between one point to all the other points for this set
now the absolute location of the random points ( minutiae points ) are different but the relative position is same.

This is the simplified concept.

Once you understand this, write a program which will make a table of relative distance for around 60 points in a 400X 250 grid ( 60X60=3600) and is able to give a match or non match result when another set of points with tilts, shifts are given.

400X250 will be the no of pixels you get if you make a image of a finger using a 500 dpi sensor. All the extracted minutiae points will be located within this grid. And in a finger print there will be approximately 50-80 minutia points .

Of course, this is greatly simplified. In really deployable applications it is much different but the fundamental is the same.

How to extract minutiae points from an finger print image is a different subject.
Guess you will be able to do it in matlab.

Best wishes


New Member
There is a lot of delay in moderating. I made a posting 3 days back and is yet to appear
Moderators : could you pl let me know if anything was wrong in my posting


New Member
Jupi>>Its a humble request to you to please suggest us which scanner should we buy that only reads the finger and give us the image (capable of Jupi>>connecting directly to computer).

Think this may be useful.

Jupi>>The biggest problem we are facing is that after reading the algorithms and reports of already made projects, we find formulae which we don't Jupi>>understand.

Ok. This requires some good understanding of mathematics, particularly trigonometry.
Will try to explain it in a simple fashion. You will be able to understand the all the advanced formulae after you are able to do this simple one.

First create an array of 400X250 and fill them all with 0.
Choose some 50 random locations in the array and then fill them all with 1.

Now note the x,y location of the 1's in the array
Add them with a constant ( x+a, y+b )
Now create another array with all zeros and 50 ones with the shift in the locations.( x1=x+a, y1=y+b )
Now the difference between the the two arrays is that, the relative location of the 1's are same but the absolute location is having a shift .

The finger print image from a 500 dpi black& white finger print scanner will be an an array of around 400X250 pixels, with each location having a value of 0 to 255 ( black to white in gray scales) If you process the image in Matlab ( i guess that you know how to do this) you will get a minutiae template as a 400X250 array with around 50 ones and rest all zero. Generally a finger will have around 50 minutiae points and the location of the 1's is the location of a minutiae point in the finger print.

Now write a program to make a list of the relative distances between each of the minutiae points in the array using trigonometric functions.
( in vector scale. ie the distance and the angel theta.) To understand it better, in a graph, mark the x,y value of the two minutiae points. Draw a line between the two minutiae points and a vertical and a horizontal line touching both the points to form the triangle

Now your program should give you 2500 distances and angles. ( 50x50)
Run the program the shifted second array set , you get another 2500.

The values will be the same. That means it is a match. Ie the two arrays are two different images of the same finger.

Guess you are able to understand this so far. But, as mentioned, this is a basic.
Only if you are able to understand this and do this, you will be able to understand the next level of advanced functions and formulae.

Best wishes


New Member
Hi Jupi... Even i am making Finger Print Verification system as my final year project. I have been looking for a simple scanner circuit for some days now, but i haven't found any as yet.

What i am planning to make is, a Scanner and a matlab code to process the image and match it with another image and give the result.

If you have found a circuit for making a scanner or any info related to it, then plz post it here... it will really help me..

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