FINGERPRINT COLLATION APPARATUS, FINGERPRINT PATTERN AREA EXTRACTING APPARATUS AND QUALITY JUDGING APPARATUS, AND METHOD AND PROGRAM OF THE SAME

• US 20070201733A1
• Filed: 02/27/2007
• Published: 08/30/2007
• Est. Priority Date: 02/27/2006
• Status: Active Grant

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: HARA, Masanori
• Granted Patent: US 7,885,437 B2
• Time in Patent Office: Days
• US Class Current: 382/124
• CPC Class Codes: G06V 40/1347 Preprocessing; Feature extraction
• CPC Class Codes: G06V 40/1359 Extracting features related to ridge properties; Determining the fingerprint type, e.g. whorl or loop

Abstract

To enable extraction of a specific area (pattern area) that includes a characteristic part of the inherent pattern of individual fingerprint from an inputted fingerprint image of a human being or other creature. The pattern area is extracted as the minimum area that is surrounded by a right pattern area slope, a left pattern area slope, and pattern area bases. The right (left) pattern area slope is a fingerprint ridge which runs towards the outside on the right (left) side from the start point that is located on the upper side of the center point of the fingerprint image, and satisfies a prescribed condition. The pattern area base is a fingerprint ridge which runs on the lower side of the center and satisfies a prescribed condition.

Claims

1. A fingerprint pattern area extraction apparatus, comprising an extracting unit for extracting a pattern area from an inputted fingerprint image.

2. The fingerprint pattern area extraction apparatus as claimed in claim 1, wherein the extracting unit extracts a smallest pattern area from the fingerprint image.

3. The fingerprint pattern area extraction apparatus as claimed in claim 2, wherein the extracting unit includes a pattern area slope extracting device and a pattern area acknowledging device, wherein

the pattern area slope extracting device extracts a lowest pattern area slope from the fingerprint image;

and

the pattern area acknowledging device extracts the smallest fingerprint pattern area based on the lowest pattern area slope.

4. The fingerprint pattern area extraction apparatus as claimed in claim 3, wherein the pattern area slope extracting device includes a right pattern area slope extracting device and a left pattern area slope extracting device, wherein

the right pattern area slope extracting device extracts a first right pattern slope by searching right pattern area slopes towards an upper direction from a center point of the fingerprint image;

and

the left pattern area slope extracting device extracts a first left pattern slope by searching left pattern area slopes towards the upper direction from the center point of the fingerprint image.

5. The fingerprint pattern area extraction apparatus as claimed in claim 4, wherein:

the right pattern area slope extracting device extracts, as the right pattern area slope, a slope that has a horizontal distance of more than a prescribed value from a start point and ends by curving downwards, among fingerprint ridges that start from the start point and run down towards right side; and

the left pattern area slope extracting device extracts, as the left pattern area slope, a slope that has a horizontal distance of more than a prescribed value from a start point and ends by curving downwards, among fingerprint ridges that start from the start point and run down towards left side.

6. The fingerprint pattern area extraction apparatus as claimed in claim 3, wherein the pattern area slope extracting device searches pattern area slopes on right and left sides from an upper part of the fingerprint image towards a lower part at a prescribed interval, and extracts lowest pattern area slopes changing in a prescribed shape.

7. The fingerprint pattern area extraction apparatus as claimed in claim 3, further comprising a pattern area feature extracting device that outputs a completeness evaluation value of the extracted pattern area based on whether or not the right pattern slope is extracted and whether or not the left pattern slope is extracted.

8. The fingerprint pattern area extraction apparatus as claimed in claim 7, wherein the pattern area feature extracting device calculates a right slope area dimension and a left slope area dimension based on the right and left pattern area slopes, and calculates dimension of the pattern area that includes a total value thereof.

9. The fingerprint pattern area extraction apparatus as claimed in claim 8, wherein the pattern area feature extracting device further outputs a right slope vertex position, a left slope vertex position, a distance between the vertexes of the right and left slopes, height of the right slope vertex, height of the left slope vertex, and angles of the right and left slopes, of the pattern area.

10. The fingerprint pattern area extraction apparatus as claimed in claim 4, further comprising a pattern area base extracting device that extracts, as pattern area bases from the fingerprint image, highest ridgelines with a curvature of less than a prescribed value, which are extended in right and left sides from a third start point that positioned beneath a center point of the fingerprint image, and a straight line connecting both ends thereof is almost horizontal, wherein

the pattern area acknowledging device for extracting the smallest fingerprint pattern area extracts the fingerprint pattern area based on the pattern area slopes and the pattern area bases.

11. The fingerprint pattern area extraction apparatus as claimed in claim 10, further comprising a pattern area feature extracting device that outputs a completeness evaluation value of the extracted pattern area based on whether or not the right pattern slope is extracted, whether or not the left pattern slope is extracted, and whether or not the pattern area bases are extracted.

12. The fingerprint pattern area extraction apparatus as claimed in claim 1, wherein the extracting unit extracts the pattern area by dividing it into a plurality of regions.

13. The fingerprint pattern area extraction apparatus as claimed in claim 1, wherein the extracting unit includes a pattern area slope extracting device and a pattern area acknowledging device, wherein

the pattern area slope extracting device extracts pattern area slopes from the fingerprint image;

and

the pattern area acknowledging device extracts the fingerprint pattern area based on the pattern area slopes.

14. A quality judging apparatus, comprising:

the extracting unit claimed in claim 3, the pattern area feature extracting device claimed in claim 7, and an evaluation unit for evaluating quality of the fingerprint image based on a pattern area feature quantity that is extracted by the pattern area feature extracting device.

15. The quality judging apparatus as claimed in claim 14, wherein the evaluation unit evaluates the quality of the fingerprint image based on the completeness evaluation value of the pattern area extracted by the pattern area feature extracting device and/or qualities of ridgelines within the pattern area.

16. A fingerprint collation apparatus, comprising:

the extracting unit claimed in claim 3, the pattern area feature extracting device claimed in claim 7, and a collation unit for collating the fingerprint image based on minutiae of fingerprint ridges within the pattern area extracted by the pattern area feature extracting device.

17. The fingerprint collation apparatus as claimed in claim 16, wherein:

the pattern area feature extracting device calculates a right slope area dimension and a left slope area dimension based on the right and left pattern area slopes, and calculates dimension of the pattern area that includes a total value thereof, and the pattern area feature extracting device further outputs a right slope vertex position, a left slope vertex position, a distance between the vertexes of the right and left slopes, height of the right slope vertex, height of the left slope vertex, and angles of the right and left slopes, of the pattern area; and

the collation unit performs fingerprint collation by using the pattern area feature quantities outputted from the pattern area feature extracting device for the collation.

18. A fingerprint collation apparatus, comprising:

the extracting unit claimed in claim 13, and a collation unit that performs fingerprint collation by using the feature quantities of the pattern area outputted from the extracting unit.

19. A program for enabling a computer to execute a function of extracting a pattern area from an inputted fingerprint image.

20. The program as claimed in claim 19, which enables the computer to execute a function of extracting a smallest pattern area from the fingerprint image.

21. The program as claimed in claim 20, which enables the computer to execute:

a pattern area slope extracting procedure for extracting lowest pattern area slopes from the fingerprint image; and

a pattern area acknowledging procedure for extracting the smallest fingerprint pattern area based on the lowest pattern area slopes.

22. The program as claimed in claim 21, wherein the pattern area slope extracting procedure comprises:

a right pattern area slope extracting procedure which extracts a first right pattern slope by searching right pattern area slopes towards an upper direction from a center point of the fingerprint image; and

a left pattern area slope extracting procedure which extracts a first left pattern slope by searching left pattern area slopes towards the upper direction from the center point of the fingerprint image.

23. The program as claimed in claim 22, wherein the right (or the left) pattern area slope is a slope among fingerprint ridges that run down towards right (or left) side from a first start point (or a second start point), which has horizontal distance of more than a first prescribed value or more than a second prescribed value from the start point, and ends by curving downwards.

24. The program as claimed in claim 21, wherein the pattern area slope extracting procedure searches pattern area slopes on right and left sides from an upper part of the fingerprint image towards a lower part at a prescribed interval, and extracts lowest pattern area slopes changing in a prescribed shape.

25. The program as claimed in claim 23, which further enables the computer to execute the pattern area feature extracting procedure that outputs a completeness evaluation value of the extracted pattern area based on whether or not the right pattern slope is extracted and whether or not the left pattern slope is extracted.

26. The program as claimed in claim 25, wherein the pattern area feature extracting procedure calculates a right slope area dimension and a left slope area dimension based on the right and left pattern area slopes, and calculates dimension of the pattern area that includes a total value thereof.

27. The program as claimed in claim 26, wherein the pattern area feature extracting procedure further outputs a right slope vertex position, a left slope vertex position, a distance between the vertexes of the right and left slopes, height of the right slope vertex, height of the left slope vertex, and angles of the right and left slopes, of the pattern area.

28. The program as claimed in claim 22, which further enables the computer to execute a pattern area base extracting procedure that extracts, as pattern area bases from the fingerprint image, highest ridgelines with a curvature of less than a prescribed value, which are extended in right and left sides from a third start point that positioned beneath a center point of the fingerprint image, and a straight line connecting both ends thereof is almost horizontal, wherein

the pattern area acknowledging device extracts the fingerprint pattern area based on the pattern area slopes and the pattern area bases.

29. The program as claimed in claim 28, which further enables the computer to execute a pattern area feature extracting procedure that outputs a completeness evaluation value of the extracted pattern area based on whether or not the right pattern slope is extracted, whether or not the left pattern slope is extracted, and whether or not the pattern area bases are extracted.

30. A program for enabling a computer to execute a procedure for evaluating quality of the fingerprint image based on pattern area feature quantities that are obtained by executing the program claimed in claim 25.

31. A program for enabling a computer to execute a procedure for evaluating quality of the fingerprint image based on the completeness evaluation value of the pattern area obtained by executing the program claimed in claim 25 and/or qualities of ridgelines within the pattern area.

32. A program for enabling a computer to execute a procedure for performing collation of the fingerprint image based on minutiae of fingerprint ridges within the pattern area obtained by executing the program claimed in claim 19.

33. A program for enabling a computer to execute a procedure for performing fingerprint collation by using the pattern area feature quantities that are obtained by executing the program claimed in claim 27.

34. The program as claimed in claim 19, which enables the computer to execute a procedure for extracting the pattern area by dividing it into a plurality of regions.

35. The program as claimed in claim 19, which enables the computer to execute:

a pattern area slope extracting procedure for extracting pattern area slopes from the fingerprint image; and

a pattern area acknowledging procedure for extracting the fingerprint pattern area based on the pattern area slopes.

36. A program for enabling a computer to execute a procedure for performing fingerprint collation by using the pattern area feature quantities that are obtained by executing the program claimed in claim 34.

37. A fingerprint pattern area extraction method, comprising the steps of:

a right pattern area slope extracting step which extracts a first right pattern slope by searching right pattern area slopes towards an upper direction from a center point of the inputted fingerprint image;

a left pattern area slope extracting step which extracts a first left pattern slope by searching left pattern area slopes towards the upper direction from the center point of the fingerprint image; and

a pattern area acknowledging step which extracts a fingerprint pattern area based on the pattern area slopes.

38. The fingerprint pattern area extraction method as claimed in claim 37, wherein the right (or the left) pattern area slope is a slope among fingerprint ridges that run down towards right (or left) side from a first start point (or a second start point), which has horizontal distance of more than a first prescribed value or a second prescribed value from the start point, and ends by curving downwards.

39. The fingerprint pattern area extraction method as claimed in claim 38, further comprising a pattern area feature extracting step which outputs a completeness evaluation value of the extracted pattern area based on whether or not the right pattern slope is extracted and whether or not the left pattern slope is extracted.

40. The fingerprint pattern area extraction method as claimed in claim 39, wherein, in the pattern area feature extracting step, a right slope area dimension and a left slope area dimension are calculated based on the right and left pattern area slopes, and dimension of the pattern area that includes a total value thereof is calculated.