Methods for finger biometric processing and associated finger biometric sensors

• US 20050129291A1
• Filed: 10/01/2004
• Published: 06/16/2005
• Est. Priority Date: 10/01/2003
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Authentec Incorporated State of Incorporation Delaware
• Inventors: Boshra, Michael
• Granted Patent: US 7,616,787 B2
• Time in Patent Office: Days
• US Class Current: 382/124
• CPC Class Codes: G06V 40/1335 Combining adjacent partial images (e.g. slices) to create a composite input or reference pattern; Tracking a sweeping finger movement

Abstract

A method is for processing a plurality of finger biometric enrollment data sets that accounts for uncertainty in alignment between finger biometric enrollment data sets. The method may include generating a respective estimated physical transformation between each pair of finger biometric enrollment data sets, and generating a respective uncertainty for each estimated physical transformation. The method may also include associating the respective estimated physical transformation and the uncertainty for each estimated physical transformation with each pair of finger biometric enrollment data sets to define a logical finger biometric enrollment graph. The logical finger biometric enrollment graph is readily used for subsequent accurate matching in either touch sensor applications or slide sensor applications.

Claims

1. A method for finger biometric processing comprising:

generating a respective estimated physical transformation between at least one pair of finger biometric enrollment data sets;

generating a respective uncertainty for each estimated physical transformation; and

associating the respective estimated physical transformation and the respective uncertainty with the at least one pair of finger biometric enrollment data sets to define a logical finger biometric enrollment graph.

2. A method according to claim 1 further comprising generating a respective confidence score for an alignment between the at least one pair of finger biometric enrollment data sets;

and wherein associating further comprises associating the respective confidence score with the at least one pair of finger biometric enrollment data sets to further define the logical finger biometric enrollment graph.

3. A method according to claim 1 wherein the at least one pair of finger biometric enrollment data sets are generated based upon successive placements of a user'"'"'s finger upon a finger biometric touch sensor.

4. A method according to claim 3 further comprising:

generating at least one finger biometric verify data set; and

comparing the at least one finger biometric verify data set with the logical finger biometric enrollment graph to determine a match therewith.

5. A method according to claim 4 wherein comparing comprises:

determining which finger biometric enrollment data set produces a highest match value with the at least one finger biometric verify data set thereby defining an anchor node of the logical finger biometric enrollment graph; and

determining a match score between the at least one finger biometric verify data set and at least one other finger biometric enrollment data set.

6. A method according to claim 5 further comprising removing redundant data of the anchor node from the at least one other finger biometric enrollment data set prior to determining the match score.

7. A method according to claim 1 wherein the at least one pair of finger biometric enrollment data sets are generated based upon sliding placement of a user'"'"'s finger upon a finger biometric slide sensor that generates a series of finger biometric enrollment data sets during sliding.

8. A method according to claim 7 further comprising:

generating a series of finger biometric verify data sets using the finger biometric slide sensor;

generating a respective estimated physical transformation between at least one pair of finger biometric verify data sets;

generating a respective uncertainty for each estimated physical transformation; and

associating the respective estimated physical transformation and the respective uncertainty with the at least one pair of finger biometric verify data sets to define a logical finger biometric verify graph.

9. A method according to claim 8 wherein generating the respective uncertainty for each estimated physical transformation between the at least one pair of finger biometric verify data sets comprises using at least one of a uniform and Gaussian probability distribution function.

10. A method according to claim 8 further comprising generating an initial alignment between the logical finger biometric enrollment graph and the logical finger biometric verify graph.

11. A method according to claim 10 further comprising comparing the logical finger biometric verify graph with the logical finger biometric enrollment graph based upon the initial alignment to determine a match therewith.

12. A method according to claim 11 further comprising removing redundant data from at least one of the logical finger biometric enrollment graph and logical finger biometric verify graph.

13. A method according to claim 11 wherein comparing the logical finger biometric verify graph with the logical finger biometric enrollment graph comprises:

generating a respective uncertainty in alignment between at least one node in the logical finger biometric verify graph and at least one node in the logical finger biometric enrollment graph;

performing constrained node-to-graph matching based upon the respective uncertainty in alignment; and

generating an overall graph matching score based upon the constrained node-to-graph matching.

14. A method according to claim 1 wherein generating the respective estimated physical transformation comprises correlating respective sub-regions in the at least one pair of finger biometric enrollment data sets.

15. A method according to claim 1 wherein each finger biometric enrollment data set comprises a finger biometric enrollment image data set, and further comprising subjecting each finger biometric enrollment image data set to at least one of image enhancement for reducing noise content, and image warping to account or non-instantaneous sensor operation or non-linear deformations.

16. A method according to claim 1 wherein the respective estimated physical transformation comprises at least one of a horizontal translation, a vertical translation, and a rotation.

17. A method according to claim 1 wherein each finger biometric enrollment data set comprises at least one of a finger image data set and a finger biometric feature set.

18. A method according to claim 1 wherein each finger biometric enrollment data set comprises a combination of finger biometric enrollment data subsets.

19. A method according to claim 1 wherein generating the respective estimated physical transformation is based upon alignment of respective edges of the at least one pair of finger biometric enrollment data sets.

20. A method according to claim 1 wherein the at least one pair of finger biometric enrollment data sets is generated by an integrated circuit finger biometric sensor.

21. A method for determining a finger biometric match comprising:

generating a plurality of finger biometric enrollment data sets;

generating a respective estimated physical transformation between at least one pair of finger biometric enrollment data sets;

generating a respective uncertainty for each estimated physical transformation;

generating a respective confidence score for an alignment between the at least one pair of finger biometric enrollment data sets;

associating the respective estimated physical transformation, the uncertainty, and the confidence score with the at least one pair of finger biometric enrollment data sets to define a logical finger biometric enrollment graph;

generating at least one finger biometric verify data set; and

comparing the at least one finger biometric verify data set with the logical finger biometric enrollment graph to determine a match therewith.

22. A method according to claim 21 wherein generating the plurality of finger biometric enrollment data sets comprises generating the plurality of finger biometric enrollment data sets based upon successive placements of a user'"'"'s finger upon a finger biometric touch sensor.

23. A method according to claim 21 wherein comparing comprises:

determining which finger biometric enrollment data set produces a highest match value with the at least one finger biometric verify data set thereby defining an anchor node of the logical finger biometric enrollment graph; and

determining a match score between the at least one finger biometric verify data set and at least one other finger biometric enrollment data set.

25. A method according to claim 21 wherein generating the plurality of finger biometric enrollment data sets comprises generating the plurality of finger biometric enrollment data sets based upon sliding placement of a user'"'"'s finger upon a finger biometric slide sensor that generates a series of finger biometric enrollment data sets during sliding.

24. (canceled)

26-34. -34. (canceled)

35. A method for processing a plurality of finger biometric data sets comprising:

generating a respective estimated physical transformation between at least one pair of finger biometric data sets;

generating a respective uncertainty for each estimated physical transformation; and

associating the respective estimated physical transformation and the respective uncertainty with the at least one pair of finger biometric data sets to define a logical finger biometric graph.

36. A method according to claim 35 further comprising generating a respective confidence score for an alignment between the at least one pair of finger biometric data sets;

and wherein associating further comprises associating the respective confidence score with the at least one pair of finger biometric data sets to define the logical finger biometric graph.

37. A method according to claim 35 wherein the respective estimated physical transformation comprises at least one of a horizontal translation, a vertical translation, and a rotation.

38. A method according to claim 35 wherein each finger biometric data set comprises at least one of a finger image data set and a finger biometric feature set.

39. A method according to claim 35 wherein generating the respective estimated physical transformation is based upon alignment of respective edges of the at least one pair of finger biometric data sets.

40. A method according to claim 35 wherein the finger biometric data sets are generated by an integrated circuit finger biometric sensor.

41. A finger biometric sensor comprising:

a finger biometric sensing area; and

a processor connected to said finger biometric sensing area for

generating a plurality of finger biometric enrollment data sets in cooperation with said finger biometric sensing area,

generating a respective estimated physical transformation between at least one pair of finger biometric enrollment data sets,

generating a respective uncertainty for each estimated physical transformation, and

associating the respective estimated physical transformation and the respective uncertainty with the at lest one pair of finger biometric enrollment data sets to define a logical finger biometric enrollment graph.

42. A finger biometric sensor according to claim 41 wherein said processor is also for generating a respective confidence score for an alignment between the at least one pair of finger biometric enrollment data sets;

and wherein said processor is also for associating the respective confidence score with the at least one pair of finger biometric enrollment data sets to further define the logical finger biometric enrollment graph.

43. A finger biometric sensor according to claim 41 wherein said processor is also for generating the plurality of finger biometric enrollment data sets based upon successive placements of a user'"'"'s finger upon said finger biometric sensing area.

44. A finger biometric sensor according to claim 41 wherein said processor is also for:

generating at least one finger biometric verify data set in cooperation with said finger biometric sensing area; and

comparing the at least one finger biometric verify data set with the logical finger biometric enrollment graph to determine a match therewith.

47. A finger biometric sensor according to claim 41 wherein said processor generates the plurality of finger biometric enrollment data sets as a series of finger biometric enrollment data sets based upon sliding placement of a user'"'"'s finger upon said finger biometric sensing area.

54. A finger biometric sensor according to claim 41 wherein said processor generates the respective estimated physical transformation based upon correlating respective sub-regions in the pair of finger biometric enrollment data sets.

55. A finger biometric sensor according to claim 41 wherein each finger biometric enrollment data set comprises a finger biometric enrollment image data set;

and wherein said processor is also for subjecting each finger biometric enrollment image data set to at least one of image enhancement for reducing noise content, and image warping to account for non-instantaneous sensing area operation or non-linear deformations.

56. A finger biometric sensor according to claim 41 wherein each estimated physical transformation comprises at least one of a horizontal translation, a vertical translation, and a rotation.

57. A finger biometric sensor according to claim 41 wherein each finger biometric enrollment data set comprises at least one of a finger image data set and a finger biometric feature set.

58. A finger biometric sensor according to claim 41 wherein each finger biometric enrollment data set comprises a combination of finger biometric enrollment data subsets.

59. A finger biometric sensor according to claim 41 wherein said processor generates the respective estimated physical transformation based upon alignment of respective edges of the at least one pair of finger biometric enrollment data sets.

60. A finger biometric sensor according to claim 41 wherein said finger biometric sensing area comprises an integrated circuit finger biometric sensing area.

45-46. -46. (canceled)

48-53. -53. (canceled)

61. A finger biometric sensor comprising:

a finger biometric sensing area;

a memory storing a logical finger biometric enrollment graph based upon a plurality of finger biometric enrollment data sets, a respective estimated physical transformation between at least one pair of finger biometric enrollment data sets, and a respective uncertainty for each estimated physical transformation; and

a processor connected to said finger biometric sensing area and said memory for

generating at least one finger biometric verify data set in cooperation with said finger biometric sensing area, and

comparing the at least one finger biometric verify set with the logical finger biometric enrollment graph to determine a match therewith.

62. A finger biometric sensor according to claim 61 wherein said memory also stores a respective confidence score for an alignment between the at least one pair of finger biometric enrollment data sets as part of the logical finger biometric enrollment graph.

63. A finger biometric sensor according to claim 61 wherein said processor compares by:

determining which finger biometric enrollment data set produces a highest match value with the at least one finger biometric verify data set thereby defining an anchor node of the logical finger biometric enrollment graph; and

determining a match score between the at least one finger biometric verify data set and at least one other finger biometric enrollment data set.

65. A finger biometric sensor according to claim 61 wherein said processor generates the at least one finger biometric verify data set by generating a series of finger biometric verify data sets in cooperation with said finger biometric sensing area;

and wherein said processor is also for;

generating a respective estimated physical transformation between at least one pair of finger biometric verify data sets;

generating a respective uncertainty for each estimated physical transformation; and

associating the respective estimated physical transformation and the respective uncertainty for each estimated physical transformation with the at least one pair of finger biometric verify data sets to define a logical finger biometric verify graph.

69. A finger biometric sensor according to claim 61 wherein each estimated physical transformation comprises at least one of a horizontal translation, a vertical translation, and a rotation.

70. A finger biometric sensor according to claim 61 wherein each finger biometric enrollment data set comprises at least one of a finger image data set and a finger biometric feature set.

71. A finger biometric sensor according to claim 61 wherein each finger biometric enrollment data set comprises a combination of finger biometric enrollment data subsets.

72. A finger biometric sensor according to claim 61 wherein said processor generates each estimated physical transformation based upon alignment of respective edges in the at least one pair of finger biometric enrollment data sets.

73. A finger biometric sensor according to claim 61 wherein said finger biometric sensing area comprises an integrated circuit finger biometric sensing area.

64. (canceled)

66-68. -68. (canceled)