Fingerprint recognition and retrieval system

• US 4,747,147 A
• Filed: 06/16/1986
• Issued: 05/24/1988
• Est. Priority Date: 09/03/1985
• Status: Expired due to Term

• Current Assignee: Malcolm K. Sparrow
• Original Assignee: Malcolm K. Sparrow
• Inventors: Sparrow, Malcolm K.
• Primary Examiner(s): Boudreau, Leo H/
• Assistant Examiner(s): Mancuso, Joseph
• Application Number:
  US06/875,023
• Time in Patent Office: 708 Days
• Field of Search: 382/4, 382/5, 382/21, 382/26, 356/71, 283/69
• US Class Current: 382/125
• CPC Class Codes: G06V 10/40 Extraction of image or video features
• CPC Class Codes: G06V 40/1347 Preprocessing; Feature extraction
• CPC Class Codes: G07C 9/37 using biometric data, e.g. fingerprints, iris scans or voice recognition

Abstract

Fingerprints are scanned by a scanning system (13). Topological systems for coding and comparing fingerprints are described, including a system for recording a description of fingerprints. In a preferred embodiment, a central point of the fingerprint is selected as a center of rotating scan line. The scan line is rotated to different topological characteristics. A code (T) representing the type of irregularity is recorded (16, 17). A measure (M) of the scanning position when encountering the irregularity is made (16, 17). In the case of a rotating scan line the angular coordinate (θ) is recorded as the measure (M) of scanning position. The ridge count (R) (16) is also recorded. A list of coordinate sets (T, θ, R) specifies the topology of a sector. For fragmentary prints similar coordinate sets are generated. A fourth coordinate can be added corresponding to the radial distance (D) (16). A full set of coordinates (T,θ, R, D) gives a complete topological and spatial description of a fingerprint. Comparison of fingerprints can then be conducted by a computer (20).

Claims

1. In a fingerprint recognition system, apparatus for extracting topological coordinates from a known fingerprint and storing composite sets of extracted topological coordinates in a machine searchable fingerprint database comprising:

means for establishing a scanning line,

means for selecting a predetermined point on said scanning line,

means for scanning said known fingerprint in a predetermined scan pattern by progressive movement of said scanning line over said known fingerprint, including each successive topological characteristic in said predetermined scan pattern and determining the scan location data (M) of each said successive topological characteristic relative to said scanning line and scanning pattern,

means for determining the number of ridge lines (R) between said predetermined point on said scanning line and each said successive topological characteristic,

means for assigning a predetermined type code (T) to each successive topological characteristic, and

means for storing said type code (T), scan location data (M) and the number of ridge lines (R) for each known fingerprint in a machine searchable database.

2. The fingerprint recognition system defined in claim 1 including a central computer coupled to said database, one or more inquiry terminals, means for connecting said one or more inquiry terminals to said central computer, each said inquiry terminal including means for extracting from an unknown latent or rolled fingerprint composite sets of topological coordinates comprising:

means for establishing a scanning line on said unknown fingerprint,

means for selecting a predetermined point on said scanning line in said unknown fingerprint,

means for scanning said unknown fingerprint in a predetermined scan pattern by progressive movement of said scanning line over said unknown fingerprint, including each successive topological characteristic in said predetermined scan pattern and determining the scan location data (Mu) of each said successive topological characteristic relative to said scanning line and scanning pattern,

means for determining the number of ridge lines (Ru) between said predetermined point on said scanning line and each said successive topological characteristic,

means for assigning a predetermined type code (Tu) to each successive topological characteristic, and

said central computer having means for comparing said topological coordinate sets (Tu, Mu, Ru) from an unknown fingerprint with the composite sets of topological coordinates in said machine searchable database to identify the known fingerprint corresponding to said unknown print.

3. The system defined in claim 2 wherein said predetermined scan pattern, both on the unknown and on the known fingerprints, is defined by rotating a line about a predetermined central point, the central point also being designated the predetermined point on the scanning line for the purpose of measuring ridge counts (R), and where said scan location data is the angle (θ

) measured from a predetermined reference line.

4. The system defined in claim 2 including file means storing replicable images of all said unknown prints and means for retrieving a replicable image of identified known print corresponding to said unknown print.

5. The system defined in claim 2 including means for retrieving an image of a known fingerprint corresponding to said unknown fingerprint.

6. The system defined in claim 5 including means for displaying an image of the fingerprint retrieved by said means for retrieving.

7. The fingerprint recognition system defined in claim 1 including, for each topological irregularity on each known fingerprint,

means for determining a distance (D) from each successive topological irregularity to the said predetermined point on said scanning line,

means for storing the distance (D) together with the coordinate sets (T, M, R) as composite coordinate sets of the form (T, M, R, D) in said machine searchable database.

8. The system defined in claim 7 wherein said predetermined scan pattern on the unknown fingerprints, is defined by rotating a line about a predetermined central point, said central point being designated the predetermined point on the scanning line for the purpose of measuring ridge counts (R) and also for the purpose of measuring the distances (D), and where said scan location data is the angle (θ

) measured from a predetermined reference line.

9. The fingerprint recognition system defined in claim 7 including a central computer coupled to said database, one or more inquiry terminals, means for connecting said one or more inquiry terminals to said central computer, each said inquiry terminal including means for extracting from an unknown latent or rolled fingerprint, composite sets of topological coordinates comprising:

means for establishing a further scanning line,

means for selecting a predetermined point on said further scanning line to be the predetermined point,

means for scanning said unknown fingerprint in a predetermined scan pattern by progressive systematic movement of said further scanning line over said unknown fingerprint, including each successive topological characteristic in said predetermined scan pattern and determining the scan location data (Mu) of each said successive topological characteristic relative to said further scanning line and scanning pattern,

means for determining the number of ridge lines (Ru) between said predetermined point on said further scanning line and each said successive topological characteristic,

means for assigning a predetermined type code (Tu) to each successive topological characteristic,

means for determining a distance (Du) from each successive topological irregularity to the said predetermined point on said further scanning line, and

said central computer having means for comparing said composite topological coordinate sets (Tu, Mu, Ru, Du) from an unknown fingerprint with the composite topological coordinate data sets in said machine searchable database to identify the known fingerprint corresponding to said unknown fingerprint.

10. The system defined in claim 9 wherein said predetermined scan pattern, both on the unknown and on the known fingerprints, is defined by rotating a line about a predetermined central point, that central point also being designated the predetermined point on the scanning line for the purpose of measuring ridge counts (R) and also for the purpose of measuring the distances (D), and where said scan location data is the angle (θ

) measured from a predetermined reference line.

11. The fingerprint recognition system defined in claim 10 including means for displaying an image of an identified known fingerprint corresponding to said unknown print.

12. The fingerprint recognition system defined in claim 9 including means for producing a visual image of an identified known fingerprint corresponding to said unknown fingerprint.

13. The system defined in claim 1 wherein said predetermined scan pattern is defined by rotating a line about a predetermined central point, that central point also being designated the predetermined point on the scanning line for the purpose of measuring ridge counts (R), and where said scan location data is the angle (R) measured from a predetermined reference line.

14. The fingerprint recognition system defined in claim 1 wherein said means for scanning said known fingerprint in a predetermined scan pattern includes means for moving a straight vertical "line" of scan horizontally across the fingerprint pattern, a point on that scanning line which is vertically below the entire fingerprint pattern being designated the predetermined point on the line for the purpose of measuring said ridge counts (R), and where said scan location data (M) is the measure of the horizontal movement of said scanning line from a predetermined vertical left hand edge.

15. The fingerprint recognition system defined in claim 1 wherein said means for scanning said known fingerprint in a scan pattern includes means for moving a straight horizontal line vertically over the fingerprint pattern starting from some predetermined bottom edge, a point on that scanning line which is horizontally to the left of the entire fingerprint pattern being designated the predetermined point on the line for the purpose of measuring said ridge counts (R), and where said scan location data (M) is the measure of the vertical movement of said scanning line from a predetermined bottom edge.

16. The fingerprint recognition and retrieval system defined in claim 15, including means for storing images of all said known prints, means for entering at least a portion of a set of said topological coordinates of an unknown print, means for searching said machine searchable data base to find a match for said portion of a set of topological coordinates, and means for retrieving and displaying said one of said image of a known print corresponding to the matching coordinate set found by said search.

17. The fingerprint recognition and retrieval system defined in claim 14, including storage means for storing replicable images of all said known prints and an image retrieval means for retrieving a replicable image from said storage means corresponding to a selected set of said topological coordinates, means for replicating and displaying an image of a print having said selected set of topological coordinates.

18. The fingerprint recognition and retrieval system defined in claim 15, including storage means for storing replicable images of all said known prints and an image retrieval means for retrieving a replicable image from said storage means corresponding to a selected set of said topological coordinates, means for replicating and displaying an image of a print having said selected set of topological coordinates.

19. The fingerprint recognition and retrieval system defined in claim 14, including storage means for storing images of all said known prints, means for entering at least a portion of a set of topological coordinates corresponding to an unknown print, means for searching said machine searchable database to find a matching coordinate sets in said database for said portion of a set of topological coordinates, and means for retrieving and displaying said one of said image of a known print corresponding to the matching coordinate set found by said search.

20. In a fingerprint recognition system, a method of extracting topological coordinates from a known fingerprint and storing composite sets of extracted topological coordinates in a machine searchable fingerprint database comprising:

placing a scanning line on said known fingerprint

selecting a point on said scanning line to be a predetermined point,

scanning said known fingerprint in a predetermined scan pattern or direction by systematic movement of said scanning line over said known fingerprint, including each successive topological characteristic in said predetermined scan pattern, determining the scan location data (M) on each said successive topological characteristic relative to said scanning line and scanning pattern,

determining the number of ridge lines (R) between said predetermined point on said scanning line and each said successive topological characteristic,

assigning a predetermined type code (T) to each successive topological characteristic, and

storing the type code (T), scan location data (M) and the number of ridge lines (R) in a machine searchable database.

21. A method of identifying an unknown fingerprint comprising the method defined in claim 20, including a method for extracting from an unknown fingerprint sets of topological coordinates comprising:

placing said scanning line on said unknown fingerprint,

selecting a point on said scanning line to be said predetermined point,

scanning said unknown fingerprint in a predetermined scan pattern or direction by systematic movement of said scanning line over said unknown fingerprint, including each successive topological characteristic in said predetermined scan pattern and determining the scan location data (Mu) of each said successive topological characteristic relative to said scanning line and scanning pattern,

determining the number of ridge lines (Ru) between said predetermined point on said scanning line and each said successive topological characteristic,

assigning a predetermined type code (Tu) to each successive topological characteristic, and

causing said topological coordinate sets for an unknown print to be compared with the topological coordinate data in said machine searchable database to identify the known print corresponding to said unknown print.

22. The method defined in claim 21 wherein said predetermined scan pattern, both on the unknown and on the known fingerprint, is defined by rotating a line about a predetermined central point, that central point also being designated the predetermined point of the scanning line for the purpose of measuring ridge counts (R), and where said scan location data is the angle (θ

) measured from a predetermined reference line.

23. The method defined in claim 22 including retrieving an image of a known print corresponding to said unknown print.

24. The method defined in claim 23 including displaying an image, at a remote site, of the retrieved fingerprint.

25. The method defined in claim 21 including providing an image file of all fingerprints in said machine searchable database, and retrieving from said image file an image of said known fingerprint corresponding to said unknown fingerprint.

26. The method defined in claim 20 including, for each topological irregularity on each known fingerprint,

determining a distance (D) from each successive topological irregularity to the said predetermined point on said scanning line,

storing the distance (D) together with the coordinate sets (T, M, R) as composite coordinate sets of the form (T, M, R, D) in a machine searchable database.

27. In a fingerprint recognition system the method defined in claim 25 including the step of extracting from an unknown latent or rolled fingerprint composite sets of topological coordinates comprising:

placing a scanning line on said unknown fingerprint,

selecting a point on said scanning line to be the predetermined point,

scanning said unknown fingerprint in a predetermined scan pattern or direction by systematic movement of said scanning line over said unknown fingerprint, including each successive topological characteristic in said predetermined scan pattern and determining the scan location data (Mu) of each said successive topological characteristic relative to said scanning line and scanning pattern,

determining the number of ridge lines (Ru) between said predetermined point on said scanning line and each said successive topological characterstic,

assigning a predetermined type code (Tu) to each successive topological characteristic,

determining a distnce (Du) from each successive topological irregularity to the said predetermined point on said scanning line, and

comparing said composite topological coordinate sets from an unknown print with the composite topological coordinate data in said machine searchable database to identify the known print corresponding to said unknown print.

28. In a fingerprint recognition system the method defined in claim 27 including displaying an image of an identified known fingerprint corresponding to said unknown print.

29. The method defined in claim 27 wherein said predetermined scan pattern, both on the unknown and on the known finerprints, is defined by rotating a line about a predetermined central point, that central point also being designated the predetermined point on the scanning line for the purpose of measuring ridge counts (R) and also for the purpose of measuring the distances (D), and where said scan location data is the angle (θ

) measured from a predetermined reference line.

30. In a fingerprint recognition system the method defined in claim 29 including retrieving an image of an identified known fingerprint corresponding to said unknown print.

31. In a fingerprint recognition system, the method defined in claim 30 including displaying an image of the retrieved fingerprint.

32. The method defined in claim 26 wherein said predetermined scan pattern on the unknown fingerprints is defined by relatively rotating a line about a predetermined central point, that central point also being designated the predetermined point on the scanning line for the purpose of measuring ridge counts (R) and also for the purpose of measuring the distances (D), and where said scan location data is the angle (θ

) measured from a predetermined reference line.

33. The method defined in claim 20 wherein said predetermined scan pattern is defined by rotating a line about a predetermined central point, that central point also being designated the predetermined point on the scanning line for the purpose of measuring ridge counts (R), and where said scan location data is the angle (θ

) measured from a predetermined reference line.

34. In a fingerprint recognition system, apparatus for extracting topological coordinates from a known fingerprint and storing composite sets of extracted topological coordinates in a machine searchable fingerprint database comprising:

means for selecting a central point on said known fingerprint,

means for successively measuring the angular orientation (θ

) relative to a predetermined reference line on said known fingerprint of each successive topological characteristic in a predetermined direction of rotation,

means for determining the number of ridge lines (R) between said central point and each said successive topological characteristic,

means for assigning a predetermined type code (T) to each successive topological characteristic, and

means for storing the type code (T), angular orientation (θ

) and number of ridge lines (R) in said machine searchable database.

35. The fingerprint recognition system defined in claim 34 including means for measuring the radial distance (D) to each said successive topological characteristic from said selected central point and including said radial distance (D) for each successive topological characteristic whereby a set of stored coordinates (T, θ

, R, D) provides a complete topological and spatial description of said known fingerprint.

36. The fingerprint recognition system defined in claim 35 including means for topologically reconstructing an image of the known fingerprint corresponding to any set of topological coordinates stored in the database, and displaying said reconstructed fingerprint at said enquiry terminal.

37. The fingerprint recognition system defined in claim 35 including means for determining the local ridge direction (λ

) for each said successive topological characteristic and storing said ridge direction (λ

) with said set of stored coordinates.

38. The fingerprint recognition system defined in claim 34 including a central computer coupled to said database, one or more enquiry terminals connectable to said central computer, each said enquiry terminal having a means for extracting from an unknown latent or rolled fingerprint composite sets of topological coordinates comprising:

means for selecting a central point on said unknown fingerprint,

means for successively measuring the angular orientation (θ

u) relative to a predetermined reference line on said unknown fingerprint of each successive topological characteristic in a predetermined direction of rotation,

means for determining the number of ridge lines (Ru) between said central point and each said successive topological characteristic,

means for assigning a predetermined type code (Tu) to each successive topological characteristic,

and said central computer having means for comparing said topological coordinate sets from an unknown print with the topological coordinate sets in said machine searchable database to identify the known print corresponding to said unknown print.

39. The fingerprint recognition system defined in claim 38 including means for displaying an image of an identified known fingerprint corresponding to said unknown fingerprint.

40. The fingerprint recognition system defined in claim 34 including means for extracting from said unknown fingerprint the distance (Du) between said central point and each successive topological characteristic,

and said central computer having means for comparing said composite topological coordinate sets from an unknown print with the composite topological coordinate sets in said machine searchable database to identify the known print corrresponding to said unknown print.

41. The fingerprint recognition system defined in claim 40 including means for retrieving and displaying an image of said known print corresponding to said unknown fingerprint.

42. A method of establishing a machine searchable library of fingerprints comprising the steps of:

(1) selecting a central point of the fingerprint as a center of a ridge scan line,

(2) relatively moving said ridge scan line to successively different topological characteristics of said fingerprint for a plurality of ridge lines,

(3) assigning a predetermined type code (T) to each said selected topological characteristic located, said type code (T) being selected from a table of predetermined topological characteristics,

(4) measuring the location (M) of said ridge scan line from a predetermined first scan line location,

(5) counting the number of ridges (R) between said center to the ridge scanned and forming a composite code (T, M, R) for each different topological characteristic,

(6) storing each composite code (T, M, R) in a machine searchable database.

43. The method defined in claim 42 in which said ridge scan line is a rotating ridge scan line having said central point as its center of rotation, including measuring the angular orientation (θ

) (where M=θ

) and radial distance (D) along said ridge scan line to each said topological characteristic and including each respective measurement as part of a composite code (T, M, R, D) stored in said machine searchable database.

44. The method defined in claim 43 including determining the local ridge direction (λ

) for each said topological characteristic, and

storing said ridge direction (λ

) as part of said composite code (T, θ

, R, D, λ

) stored in said machine searchable database.

45. A method for coding an uknown latent or rolled finerprint comprising the steps of:

(1) locating a central point of the fingerprint as a center of a rotating ridge scan line,

(2) relatively rotating said ridge scan line to different topological characteristics of said fingerprint for a plurality of ridge lines,

(3) assigning a predetermined type code (T) to each said selected topological characteristic located,

(4) measuring the angular orientation (θ

) of said ridge scan line from a predetermined first angular orientation,

(5) counting the number of ridges (R), between said center to the ridge scanned, and

(6) forming a composite code (T, θ

, R) for each different topological characteristic on the print.

46. A method of identifying an unknown latent or rolled fingerprint in a rolled fingerprint database comprised of rolled fingerprints coded in topological coordinate set format wherein the ridge characteristics and other irregularities are coded by their type (T), relative angular orientation (θ

) about a selected central observation point and from a predetermined line of reference, and the number of ridges (R) from said central feature, comprising the steps of;

(1) topologically coding said unknown fingerprint in the same code format as the said rolled fingerprint,

(2) topologically reconstructing the rolled fingerprint and the unknown print from the topological coordinate sets for a given rolled fingerprint stored in said database and the topological coordinate set for said unknown print,

(3) comparing vectors extracted from such topological reconstruction to obtain an identity of said unknown fingerprint.

47. In a fingerprint recognition system, the method defined in claim 46 including displaying an image of the fingerprint identified in step (3).

48. The method as described in claim 46 including the step of extracting from an unknown fingerprint a radial distance (D) for each successive topological characteristic, and forming composite coordinate sets of the type (T, θ

, R, D) and

comparing said composite topological coordinate sets from an unknown print with the topological coordinate data in said machine searchable database to identify the known print corresponding to said unknown print.

49. The method as described in claim 48 including displaying an image of the retrieved fingerprint.

50. A method of displaying a replica of a fingerprint, comprising:

topologically reconstructins an image of said fingerprint corresponding to a set of topological coordinates of the form (T, M, R, D) stored in a machine searchable database, wherein;

(T) is an irregularity type,

(M) is the scan location data for the irregularity derived by a moving scan line from a predetermined point,

(R) is the number of ridges crossed by said moving scan line from said predetermined point to the irregularity,

(D) is the distance from the irregularity to said predetermined point on said scan line, and

displaying said reconstructed fingerprint image at an enquiry terminal coupled to said machine searchable database.

51. The method of displaying a replica of a fingerprint as defined in claim 50 wherein said scan location is derived by scanning a straight scan line across the fingerprint from said predetermined point to each irregularity and said scan location data is a function of the movement of said scan line.

52. The method of displaying a replica of a fingerprint as defined in claim 51 wherein said scan location data (M) is the angle (θ

) rotatively traversed about a selected central observation point on the fingerprint by a radial scan line from said predetermined point to said irregularity.

53. The method of displaying a replica of a fingerprint as defined in claim 52 wherein said selected central observation point of said radial scan line is off-set from a central core of said fingerprint.

54. The method of displaying a replica of a fingerprint as defined in claim 51 wherein said scan location data (M) is derived by moving a straight vertical line horizontally across said fingerprint pattern, and is the measure of horizontal movement of said vertical line from a predetermined vertical edge thereof.

55. The method of displaying a replica of a fingerprint as defined in claim 51 wherein said scan location data (M) is derived by moving a straight horizontal line vertically across said fingerprint pattern and is the measure of vertical movement of said line from a horizontal edge thereof.

56. A method of displaying a replica of a fingerprint comprising,

storing at least one set of topological coordinates for the minutiae of a fingerprint, of the form (T, M, R, D) wherein,

T is a type code for each minutiae, said type code being selected from a predetermined table of minutiae types,

M is the scan line location data of each successive minutiae in a predetermined movement pattern of a scan line over a fingeprint,

R is the number of ridge lines between a predetermined point on said scan line and each successive minutiae encountered by said scan line in its predetermined movement pattern over said fingerprint,

D is the distance from the minutiae to said predetermined point,

topologically reconstructing an image of said fingerprint from said one set of topological coordinates, and

displaying said image.

57. Fingerprint coding apparatus for coding an unknown latent or rolled fingerprint comprising the steps of:

means for locating a central point of the fingerprint as a center of rotating ridge scan line,

means for relatively rotating said ridge scan line to different topological characteristics of said fingerprint for a plurality of ridge lines,

means for assigning a predetermined type code (T) to each said selected topological characteristics located,

means for measuring the angular orientation (θ

) of said ridge scan line from a predetermined first angular orientation,

means for counting the number of ridges (R), between said center to the each said topological characteristic, and means for forming a composite code (T, θ

, R) for each different topological characteristic on the print.

58. Apparatus for identifying an unknown latent or rolled fingerprint in a rolled fingerprint database comprised of rolled fingerprints coded in topological coordinate set format wherein the ridge characteristics and other irregularities are coded by their type (T), relative angular orientation (θ

) about a selected central feature observation point and from a predetermined line of reference, and the number of ridges (R) from said central feature, comprising;

(1) means for topologically coding said unknown fingerprint in the same code format as the said rolled fingerprint,

(2) means for topologically reconstructing the rolled fingerprint and the unknown print from the topological coordinate sets for a given rolled fingerprint stored in said database and the topological coordinate set for said unknown print,

(3) means for comparing vectors extracted from such topological reconstruction to obtain an identity of said unknown fingerprint.

59. Apparatus described in claim 58 including a means for extracting from an unknown fingerprint a radial distance (D) for each successive topological characteristic, and forming composite coordinate sets of the type (T, θ

, R, D), and

means for comparing said composite topological coordinate sets from an unknown print with the topological coordinate data in said machine searchable database to identify the known print corresponding to said unknown print.

60. A fingerprint recognition and retrieval system comprising:

storage means for storing a plurality of sets of topological coordinates for the minutes for a corresponding plurality of known fingerprints, each of said sets of topological coordinates being of the form (T, M, R) wherein,

"T" is a predetermined type code for each said type code being selected from a predetermined table of minutiae types,

"M" is the scan line location data of each successive minutiae in a predetermined movement pattern of a scan line over the fingerprint, and

"R" is the numer of ridge lines between a predetermined point on said scan line and each successive minutiae encountered by said scan line in its predetermined movement pattern over said fingerprint,

terminal means for entering a set of topological coordinates of the same form for the minutiae for at least a portion of an unknown fingerprint,

means for comparing said set of topological coordinates for at least a portion of an unknown fingerprint with said plurality of sets of topological coordinates corresponding to said plurality of known fingerprints, to locate a match therefor and,

means for retrieving a matching known fingerprint.

61. A fingerprint recognition and retrieval system as defined in claim 60 including a display means, and means for reconstructing an image of said matching known fingerprints on said display means.

62. A fingerprint recongition system as defined in claim 60 including means for topologically reconstructing an image of said matching known fingerprint and display means for displaying said image.

63. A method of establishing a machine searchable library of fingerprints having minutiae distributed in a pattern unique to the individual to whom the print belongs comprising the steps of:

scanning the fingerprint to obtain a set of topological coordinates,

said set of topological coordinates being of the form (T, M, R, D) wherein,

T is a type code for each minutiae, said type code being selected from a predetermined table of minutiae types,

M is the scan line location data of each successive minutiae in a predetermined movement pattern of a scan line over a fingerprint,

R is the number of ridge lines between a predetermined point on said scan line and each successive minutiae encountered by said scan line in its predetermined movement pattern over said fingerprint, and

D is the distance from the minutiae to said predetermined point,

topologically reconstructing said fingerprint from said set of topological coordinates.

64. The method described in claim 63 wherein said step of topologically reconstructing a fingerprint includes forming a continuity matrix and lifting said vector out of said continuity matrix.

65. A method of identifying an unknown fingerprint comprising the steps of:

forming a library as described in claim 63,

scanning the unknown fingerprint to obtain a set of topological coordinates,

topologically reconstructing said unknown fingerprint from said set of topological coordinates,

extracting a vector from said topologically reconstructed unknown fingerprint,

comparing said vector for said unknown fingerprint with said vectors in said library to identify said unknown fingerprint.

66. The method described in claim 65 including the step of retrieving and displaying an image of the known fingerprint from said machine searchable library that corresponds to said unknown fingerprint.

67. In a fingerprint recognition system, apparatus for extracting topological coordinates from a known fingerprint and storing composite sets of extracting topological coordinates in a machine searchable fingerprint database and a central computer coupled to said database and one or more inquiry terminals connected to said comprising,

means for establishing a scanning line,

means for selecting a predetermined point on said scanning line,

means for scanning said known fingerprint in a predetermined scan pattern by progressive movement of said scanning line over said known fingerprint, including each successive topological characteristic in said predetermined scan pattern and determining the scan location data (M) of each said successive topological characteristic relative to said scanning line and scanning pattern,

means for determining the number of ridge lines (R) between said predetermined point on said scanning line and each said successive topological characteristic,

means for assigning a predetermined type code (T) to each successive topological characteristic, each said type code (T) being selected from a predetermined table of topological characteristics,

means for storing said type code (T), scan location data (M) and the number of ridge lines (R) for each successive topological characteristic of said known fingerprint in a machine searchable database,

each said inquiry terminal means including means for extracting from an unknown latent or rolled fingerprint, including fingerprints where no core or delta are detected, and portions of latent prints, sets of topological coordinates comprising:

means for establishing a scanning line on said unknown fingerprint,

means for selecting a predetermined point on said scanning line scanning said unknown fingerprint,

means for scanning said unknown fingerprint in said predetermined scan pattern by progressive movement of said scanning line over said known fingerprint, including each successive topological characteristic in said predetermined scan pattern and determining the scan location data (Mu) of each said topological characteristic relative to said scanning line and scanning pattern,

means for determining the number of ridge lines (Ru) between said predetermined point on said scanning line and each said successive topological characteristic,

means for assigning a predetermined type code (Tu) to each successive topological characteristic encountered by said scan line, said type code (Tu) being selected from said predetermined list of topological characteristics, and

said central computer having means for comparing said topological coordinate sets (Tu, Mu, Ru) from said unknown fingerprint with the composite sets of topological coordinate sets in said machine searchable database to identify the known fingerprint corresponding to said unknown print.

68. The system defined in claim 67 including the file means storing replicable images of all said known prints and means for retrieving a replicable image of an identified known print corresponding to said unknown print.

69. The system defined in claim 68 including means for retrieving an image of a known fingerprint corresponding to said unknown fingerprint.

70. The system defined in claim 76 including means for displaying an image of the fingerprint retrieved by said means for retrieving.

71. The fingerprint recognition system defined in claim 67 including, for each topological irregularity on each known fingerprint, means for determining a distance (D) from each successive topological irregularity to the said predetermined point on said scanning line,

means for storing said distance (D) together with the coordinate sets (T, M, R) as composite coordinate sets of the form (T, M, R, D) in said machine searchable database,

and for each unknown fingerprint means for determining a distance (Du) from each successive topological irregularity thereof to the said predetermined point on said scanning line, and

said central computer having means for comparing composite topological coordinate sets of the form (Tu, Mu, Ru, Du) from an unknown fingerprint with the composite topological coordinate data sets in said machine searchable database to identify the known fingerprint corresponding to said unknown fingerprint.

72. The fingerprint recognition system defined in claim 71 including means for producing a visual image of an identified known fingerprint corresponding to said unknown fingerprint.

73. The system defined in claim 71 wherein said predetermined scan pattern is defined by angularly rotating a line about a predetermined central point, that central point also being designated the predetermined point on the scanning line for the purpose of measuring ridge counts (R), and where said scan location data (M) is the angle (θ

) through which said line has been angularly rotated as measured from a predetermined reference line.

74. The fingerprint recognition system defined in claim 71 wherein said means for scanning said known fingerprint in a predetermined scan pattern includes means for moving a straight vertical scan line horizontally across the fingerprint pattern, a point on said scan line which is vertically beyond the entire fingerprint pattern being designated the predetermined point on the line for the purpose of measuring said ridge counts (R), and where said scan location data (M) is the measure of the horizontal movement of said scanning line from a predetermined vertical edge.

75. The fingerprint recognition system defined in claim 71 wherein said means for scanning said known fingerprints in a scan pattern includes means for moving a straight horizontal line vertically over the fingerprint pattern starting from a predetermined edge, a point on that scanning line which is horizontally to one side of the entire fingerprint pattern being designated the predetermined point on the line for the purpose of measuring said ridge counts (R), and where said scan location data (M) is the measure of the vertical movement of said scanning line from said predetermined edge.

76. The fingerprint recognition and retrieval system defined in claims 73, 74, or 75, including storage means for storing images of all said known prints, means for entering a set of topological coordinates corresponding to a portion of an unknown fingerprint, means for searching said machine searchable database to find a matching coordinate set in said database for said portion of an unknown fingerprint, and means for retrieving and displaying said one of said image of a known fingerprint corresponding to the matching coordinate set found by said search.

77. A fingerprint recognition method comprising:

extracting topological coordinates from a known fingerprint and storing composite sets of extracted topological coordinates in a machine searchable fingerprint database by;

placing a scanning line on said known fingerprint

selecting a point on said scanning line to be a predetermined point,

scanning said known fingerprint in a predetermined scan pattern and direction by systematic movement of said scanning line over said known fingerprint, including each successive topological irregularity in said predetermined scan pattern,

determining the scan location data (M) of each said successive topological irregularity relative to said scanning line and scanning pattern,

determining the number of ridge lines (R) between said predetermined point on said scanning line and each said successive topological irregularity,

assigning a predetermined type code (T) to each successive topological irregularity, said type code (T) being selected from a predetermined table of topological irregularities, and

storing the type code (T), scan location data (M) and the number of ridge lines (R) in a machine searchable database,

with respect to unknown fingerprints including scene of crime fingerprints and fingerprints where no core or delta is detected

extracting sets of topological coordinates comprising;

placing said scanning line on said unknown fingerprint,

selecting a point on said scanning line to be said predetermined point,

scanning said unknown fingerprint in a predetermined scan pattern and direction by systematic movement of said scanning line over said unknown fingerprint, including each successive topological irregularity in said predetermined scan pattern and determining the scan location data (Mu) of each said successive topological characteristic relative to said scanning line and scanning pattern,

determining the number of ridge lines (Ru) between said predetermined point on said scanning line and each said successive topological characteristic,

assigning a predetermined type code (Tu) to each successive topological characteristic, said type code (Tu) being selected from said predetermined table of topological irregularities, and

causing said topological coordinate sets for an unknown print to be compared with the topological coordinate data in said machine searchable database to identify the known print corresponding to said unknown print.

78. A method of displaying a replica of a fingerprint comprising:

topologically reconstructing at least a portion of an image of said fingerprint corresponding to a set of topological coordinates of the form (T, M, R, D) stored in a machine searchable database, wherein;

(T) is a code for an irregularity type selected from a predetermined table of irregularity types,

(M) is the scan location data for the irregularity derived by moving a scan line from a predetermined point,

(R) is the number of ridges crossed by said moving scan line from said predetermined point to the irregularity,

(D) is the distance from the irregularity to said predetermined point on said scan line, and

displaying said reconstructed fingerprint image at an inquiry terminal coupled to said machine searchable database.

79. Apparatus for identifying an unknown latent or rolled fingerprint in a rolled fingerprint database comprised of rolled fingerprints coded in topological coordinate set format wherein the ridge characteristics and other irregularities are scanned and coded by their type (T) selected from a predetermined table of irregularity types, scan location data (M) relative to a predetermined point of reference, and the number of ridges (R) from said predetermined point of reference comprising:

(1) means for topologically coding said unknown fingerprint in the same code format as the said rolled fingeprint,

(2) means for topologically reconstructing at least a portion of the rolled fingerprint and the unknown print from the topological coordinate sets for a given rolled fingerprint stored in said database and the topological coordinate set for said unknown print,

(3) means for extracting vectors from each topologically reconstructed fingerprint,

(4) means for comparing vectors extracted from such topological reconstruction to obtain an identity of said unknown fingerprint.

80. A fingerprint recognition system comprising

with respect to known fingerprints,

storage means forming a computer database of machine searchable known fingerprints including:

means for scanning each said known fingerprint in its entirety in a predetermined direction of scan and locating each ridge event or irregularity, and extracting and storing the following data,

a type code for each ridge event or irregularity, said type code being selected from a predetermined table of type codes including the following possible ridge events or irregularities;

a. whether a ridge ends or begins relative to said predetermined direction of scan,

b. bifurcation of a ridge and the direction of the bifurcation relative to said predetermined direction of scan,

c. ridge running into or out of an unclear and/or scarred area relative to said predetermined direction of scan,

d. ridge running out of or coming into sight relative to said predetermined direction of scan,

the number of ridges between a selected point on the fingerprint and the event or irregularity, and

the distance from a predetermined point in said print to said event or irregularity, and

with respect to unknown and scene of crime fingerprints,

one or more terminals, each terminal including means for scanning an unknown fingerprint or scene of crime fingerprint in said predetermined direction of scan and extracting and storing data for said unknown and scene of crime fingerprints as set forth above with respect to said known fingerprints, and

computer means for comparing the data for said unknown and scene of crime fingerprints with data for said known fingerprints stored in said computer database to locate a match therefore, and

means for retrieving a matching known fingerprint.

81. A fingerprint recognition system comprising, in combination,

with respect to known fingerprints:

storage means forming a computer database of machine searchable known fingerprints including;

means for scanning each said known fingerprint in its entirety in a predetermined single direction of scan and locating each ridge event or irregularity, and extracting and storing the following data;

firstly, a type code (T) for each ridge event or irregularity, said type code being selected from a predetermined table of type codes including the following possible ridge events or irregularities;

a. whether a ridge ends or begins relative to said predetermined direction of scan,

b. bifurcation of a ridge and the direction of the bifurcation relative to said predetermined single direction of scan,

c. ridge running into or out of an unclear and/or scarred area relative to said predetermined single direction of scan,

d. ridge appearing or disappearing at the edge of said fingerprint relative to said pedetermined single direction of scan,

secondly, further information including the scan location data (M) of each successive ridge event or irregularity in said predetermined direction of scan such that the order in which said ridge events or irregularities are scanned can be determined and ridge count data (R) for each ridge event or irregularity to specify the topological position of each ridge event or irregularity and enable the topological relationship between each ridge event or irregularity to be reconstructed,

with respect to unknown and scene of crime fingerprints;

one or more terminals, each terminal including means for scanning an unknown fingerprint or scene of crime fingerprint in its entirety in the same predetermined single direction of scan as for said known fingerprints to locate each ridge event or irregularity, and extracting and storing the following data for said unknown and scene of crime fingerprint;

firstly, a type code (T) for each event or irregularity selected from said predetermined table of type codes as set forth above with respect to said known fingerprints,

secondly, further information including the scan location data (Mu) of each successive event or irregularity in said predetermined single direction of scan of said unknown fingerprint such that the order in which said ridge events or irregularities are scanned can be determined, and ridge count data (Ru) of each successive event or irregularity to specify the topological position of each ridge event or irregularity to enable the topological relationship between each ridge event or irregularity to be reconstructed,

computer means for comparing the data for said unknown and scene of crime fingerprints with data for said known fingerprints stored in said computer database to locate a match therefore, and

means for retrieving a matching known fingerprint.

82. The fingerprint recognition system defined in claim 81 including file means storing replicable images of all said known prints and means for retrieving a replicable image of an identified known print corresponding to said unknown print.

83. The fingerprint recognition system defined in claim 82 including means for retrieving an image of a known fingerprint corresponding to said unknown fingerprint.

84. The fingerprint recognition system defined in claim 83 including display means for displaying an image of the fingerprint retrieved by said means for retrieving.

85. The fingerprint recognition system defined in claim 81 including display means for producing a visual image of an identified known fingerprint corresponding to said unknown fingerprint.

86. A fingerprint recognition system comprising, in combination,

with respect to known fingerprints:

scanning each said known fingerprint in its entirety in a predetermined single direction of scan and locating each ridge event or irregularity, and extracting and storing the following data in a computer database of machine searchable file fingerprints;

firstly, a type code (T) for each ridge event or irregularity, said type code being selected from a predetermined table of type codes including the following possible ridge event or irregularities;

a. whether a ridge ends or begins relative to said predetermined direction of scan,

b. bifurcation of a ridge and the direction of the bifurcation relative to said predetermined direction of scan,

c. ridge running into or out of an unclear and/or scarred area relative to said predetermined direction of scan,

d. ridge appearing or disappearing at the edge of said fingerprint relative to said predetermined direction of scan,

secondly, further information including scan location data (M) of each successive event or irregularity in said predetermined single direction of scan such that the order in which said ridge events or irregularities are scanned can be determined for the entire fingerprint and ridge count data (R) of each successive event or irregularity which specifies the topological position of each ridge event or irregularity and enable the topological relationship between each ridge event or irregularity to be reconstructed,

with respect to unknown and scene of crime fingerprints;

scanning an unknown fingerprint or scene of crime fingerprint in the same predetermined single direction of scan to locate each ridge event or irregularity, and extracting and storing data for said unknown and scene of crime fingerprints including a type code (Tu) and scan location data (Mu) and ridge count data (Ru) of each successive ridge event or irregularity in said predetermined single direction of scan in the identical manner as set forth above with respect to said file fingerprints,

comparing the data for said unknown and scene of crime fingerprints with data for said file fingerprints stored in said computer database to locate a match therefore, and

retrieving a matching file fingerprint.