Pattern recognition system
First Claim
1. A system for electronically investigating a pattern that can be divided into an array of points, the system comprising:
- signal producing means for producing an electrical signal for each point on a matrix of points, said matrix having "K" points by "L" points, wherein K and L are real integers with one representing the points in the matrix line and the other representing the points in a matrix column, said signal producing means providing a serial stream of signals;
selecting means for progressively selecting locatable known groups of said produced electrical signals, which groups correspond to subarrays of said points, each said subarray having M lines by N columns, including a peripheral set of 2(M-2)+2N points and a central set of M×
N-2(M-2)-2N points, wherein said selecting means is comprised of a first storage means for storing and providing said electrical signals from said signal producing means on a first-in, first-out basis;
first determining means for checking and determining for each selected group of said signals whether a first, preselected number of signals corresponding to said central set of points have a first predetermined value and hence whether there is a central hit;
second determining means for checking and determining for each selected group of signals whether no more than a second, preselected number of the signals corresponding to said peripheral set of points have a second predetermined value, and hence whether there is a peripheral hit, wherein said second determining means comprises a memory means for storing 22(M-2)+2N coded outputs, said memory means having an enable input and 2(M-2)+2N address lines which are connected to said 2(M-2)+2N peripheral storage cells; and
said first determining means comprises gate means, the inputs of which are connected to said central storage cells and the output of which is connected to said enable input, said gate means for providing an output signal to enable said memory means when said central storage cells contain said first preselected number of signals such that said memory means outputs the data stored at the memory address indicated by the signals stored in said peripheral storage cells;
third determining means responsive to said first and second determining means for determining the location of each subarray of points for which a central hit and a peripheral hit for the same group of corresponding signals were determined; and
memory means for storing each determined location.
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Accused Products
Abstract
A pattern recognition system which detects line bifurcations and line endings, denoted minutiae, in a pattern of lines such as are found in a fingerprint is disclosed. In one embodiment, an image of a pattern is focused on a conventional matrix of image sensors or pixels. An interface circuit serially reads the voltages from the pixels and applies them to an automatic, programmable threshold detector which optimally selects a cutoff voltage and outputs a binary signal representative of the presence of a point to a minutiae detection circuit. One part of this circuit electrically reforms the matrix on a first-in-first-out basis and simultaneously forms a smaller submatrix or window. Another part of the detection circuit determines firstly if a point is present in the central array of the window, and if so, secondly whether no more than two points, which are also contiguous, are present in the peripheral part of the submatrix. In such a case, a minutia has been located and a memory stores the address of the window.
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Citations
32 Claims
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1. A system for electronically investigating a pattern that can be divided into an array of points, the system comprising:
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signal producing means for producing an electrical signal for each point on a matrix of points, said matrix having "K" points by "L" points, wherein K and L are real integers with one representing the points in the matrix line and the other representing the points in a matrix column, said signal producing means providing a serial stream of signals; selecting means for progressively selecting locatable known groups of said produced electrical signals, which groups correspond to subarrays of said points, each said subarray having M lines by N columns, including a peripheral set of 2(M-2)+2N points and a central set of M×
N-2(M-2)-2N points, wherein said selecting means is comprised of a first storage means for storing and providing said electrical signals from said signal producing means on a first-in, first-out basis;first determining means for checking and determining for each selected group of said signals whether a first, preselected number of signals corresponding to said central set of points have a first predetermined value and hence whether there is a central hit; second determining means for checking and determining for each selected group of signals whether no more than a second, preselected number of the signals corresponding to said peripheral set of points have a second predetermined value, and hence whether there is a peripheral hit, wherein said second determining means comprises a memory means for storing 22(M-2)+2N coded outputs, said memory means having an enable input and 2(M-2)+2N address lines which are connected to said 2(M-2)+2N peripheral storage cells; and
said first determining means comprises gate means, the inputs of which are connected to said central storage cells and the output of which is connected to said enable input, said gate means for providing an output signal to enable said memory means when said central storage cells contain said first preselected number of signals such that said memory means outputs the data stored at the memory address indicated by the signals stored in said peripheral storage cells;third determining means responsive to said first and second determining means for determining the location of each subarray of points for which a central hit and a peripheral hit for the same group of corresponding signals were determined; and memory means for storing each determined location. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24)
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25. A system for electronically investigating a finger print pattern which can be divided into an array of points and for identifying an individual based on the finger print of that individual, the system comprising signal producing means for producing electrical signals corresponding to said points, and which comprises a video camera means selecting means for progressively selecting locatable known groups of said produced electrical signals, which groups correspond to subarrays of said points, each said subarray having M lines by N columns, including a peripheral set of 2(M-2)+2N points and a central set of M×
- N-2(M-2)-2N points;
first determining means for checking and determining for each selected group of said signals whether a first, preselected number of the signals corresponding to said central set of points have a first predetermined value and hence whether there is a central hit; second determining means for checking and determining for each selected group of said signals whether no more than a second, preselected number of the signals corresponding to said peripheral set of points have a second predetermined value, and hence whether there is a peripheral hit; third determining means responsive to said first and second determining means for determining the location of each subarray of points for which a central hit and a peripheral hit for the same group of corresponding signals were determined; memory means for storing each determined location; and an image enhancer for producing said pattern of lines from the finger print of an individual, said enhancer comprising a transparent window in optical communication with said video camera means, an elastomeric, light colored membrane and a viscous, opaque liquid interposed between said window and said membrane. - View Dependent Claims (26, 27, 28, 29, 30, 31, 32)
- N-2(M-2)-2N points;
Specification