Card-compatible biometric access control system

1. A card-compatible biometric system for access control, comprising:

a biometric reader;

a processor and memory, wherein the processor is configured to perform the following actions:

receive biometric data from the biometric reader;

process the biometric data in such a way as to obtain a numerical code, wherein the numerical code is in the same format as a numerical code used by an access card, wherein the access card is also used to obtain access in the system;

a communication module, wherein the communication module communicates with a server;

a server, wherein the server comprises a database of users, wherein the database comprises at least one numerical code associated with a user's name, wherein no other biometric data is stored in the database.

2. The card-compatible biometric system of claim 1 , wherein the numerical code is in one of the following formats: 26-bit, 32 bit, 35 bit, 36 bit, 64 bit.

3. The card-compatible biometric system of claim 1 , wherein the biometric reader is one of the group comprising: a fingerprint reader, a face reader, an iris reader, a voice reader, a vein reader.

4. The card-compatible biometric system of claim 1 , wherein the biometric reader is a fingerprint reader, and wherein the processor is configured to process the biometric data by performing the following steps:

receive a fingerprint image from the fingerprint reader;

normalize the fingerprint image;

extract minutiae points from the image;

create a matrix from the minutiae data, wherein the matrix comprises the following four columns:

a first column comprising a row index for each minutiae point;

a second column comprising a column index for each minutiae point;

a third column comprising an orientation angle for each minutiae point;

a fourth column comprising a code for a type of minutiae, wherein the type is selected from the following group: termination point, bifurcation point, and normal ridge pixel;

converting the matrix to a unique number;

converting the unique number to a numerical code used by an access card.

5. The card-compatible biometric system of claim 1 , wherein the numerical code comprises:

a one-bit parity code;

a facility code;

a user/card code;

a one-bit parity code.

6. A method for retrofitting biometric access onto an existing card-based access system, wherein the system comprises at least one access card, comprising:

receiving biometric data using a biometric reader;

converting the biometric data to a matrix;

converting the matrix to a numerical code, wherein the numerical code is in the same format as a numerical code used by the at least one access card;

storing the numerical code in a database.

7. The method of claim 6 , wherein the biometric reader is a fingerprint reader and the biometric data is a fingerprint image.

8. The method of claim 7 , wherein the step of converting the biometric data to a matrix comprises:

extracting minutiae from the fingerprint image;

creating a matrix, wherein the matrix comprises four columns, wherein:

a first column comprises a row index for each minutiae point;

a second column comprises a column index for each minutiae point;

a third column comprises an orientation angle for each minutiae point;

a fourth column comprises a code for a type of minutiae, wherein the type is selected from the following group: termination point, bifurcation point, and normal ridge pixel.

9. The method of claim 6 , wherein the biometric reader is one of the group comprising: a face reader, a voice reader, an iris reader, a vein reader.

10. The method of claim 6 , wherein the step of converting the matrix to a numerical code comprises using a matrix to string conversion algorithm.

11. The method of claim 6 , wherein the numerical code is in one of the following Wiegand formats: 26-bit, 32 bit, 35 bit, 36 bit, 64 bit.

12. The method of claim 6 , wherein the numerical code comprises:

a one-bit parity code;

a facility code;

a user/card code;

a one-bit parity code.

13. The method of claim 6 , further comprising:

prior to the step of receiving biometric data, selecting a desired access card format;

configuring the processor to generate a numerical code in the desired access card format.