Vanishing point detecting system, vanishing point detecting method, and vanishing point detecting program

• US 8,396,299 B2
• Filed: 11/06/2007
• Issued: 03/12/2013
• Est. Priority Date: 11/08/2006
• Status: Active Grant

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Sakurai, Kazuyuki
• Primary Examiner(s): Wu, Jingge
• Application Number:
  US12/514,108
• Publication Number:
  US 20100080467A1
• Time in Patent Office: 1,953 Days
• Field of Search: 382199-201
• US Class Current: 382/201
• CPC Class Codes: G06T 2207/10016 Video; Image sequence
• CPC Class Codes: G06T 2207/30256 Lane; Road marking
• CPC Class Codes: G06T 7/13 Edge detection
• CPC Class Codes: G06T 7/60 Analysis of geometric attributes
• CPC Class Codes: G06V 10/48 by mapping characteristic values of the pattern into a parameter space, e.g. Hough transformation
• CPC Class Codes: G06V 20/588 Recognition of the road, e.g. of lane markings; Recognition of the vehicle driving pattern in relation to the road
• CPC Class Codes: G08G 1/167 Driving aids for lane monitoring, lane changing, e.g. blind spot detection

Abstract

Disclosed is a vanishing point detecting system that includes a straight line detecting unit, a vanishing point detecting unit, and a vanishing point outputting unit. In the vanishing point detecting unit, a vanishing point is detected with one evaluation index of vanishing point plausibility being whether or not angles of plural straight lines passing through a point in question or a vicinity thereof are sparsely distributed over a relatively wide range.

Claims

1. A vanishing point detecting system comprising:

a straight line detecting unit that detects a straight line from an image;

a straight line angular variation evaluation value assigning unit that assigns, for each point in a space including at least a portion of the image, when angles of straight lines that pass through the point or through a prescribed range surrounding the point are sparsely distributed over a relatively wide range, a straight line angular variation evaluation value having a larger value; and

a vanishing point detecting unit that, using, as a vanishing point evaluation value, the straight line angular variation evaluation value, detects, as a vanishing point, a point at which the straight line angular variation evaluation value has a relatively large value in comparison with other points.

2. The vanishing point detecting system according to claim 1, wherein the straight line angular variation evaluation value assigning unit calculates, with regard to a point through which a plurality of straight lines pass or a vicinity of a point through which a plurality of straight lines pass, in the image, the straight line angular variation evaluation value, as an evaluation value which represents extent of variation of angles of the straight lines, and

the vanishing point detecting unit detects, as a vanishing point, a point at which, using a straight line angular variation evaluation value that is derived corresponding to a point through which a plurality of straight lines pass or a vicinity of the point through which the plurality of straight lines pass, as an index of vanishing point plausibility, the straight line angular variation evaluation value has a relatively large value in comparison with straight line angular variation evaluation values derived for other points.

3. The vanishing point detecting system according to claim 1, wherein the straight line detecting unit detects a straight line by a Hough transform, and uses a voting value of the Hough transform of the straight line as a confidence factor for the straight line.

4. The vanishing point detecting system according to claim 1, wherein a statistical value concerning the angles of the straight lines is used as the straight line angular variation evaluation value.

6. The vanishing point detecting system according to claim 1, wherein a confidence factor bias for the straight lines between a right bottom region and a left bottom region of a point in question is used as the straight line angular variation evaluation value.

7. The vanishing point detecting system according to claim 1, wherein the image comprises image data obtained from an in-vehicle sensor, and

a vanishing point with regard to a lane marker representing a driving lane and/or a road edge is detected as the vanishing point.

8. A vehicle surrounding environment recognition system comprising the vanishing point detecting system according to claim 1, wherein a positional relationship between vehicle and surrounding environment is calculated, based on a position of the vanishing point.

9. The vehicle surrounding environment recognition system according to claim 8, wherein a pitch angle between a road surface and a direction in which the vehicle is heading is calculated, as a positional relationship of the vehicle and the surrounding environment.

5. A vanishing point detecting system comprising:

a straight line detecting unit that detects a straight line from an image;

a straight line angular variation evaluation value assigning unit that assigns, for each point in a space including at least a portion of the image, when angles of straight lines that pass through the point or through a prescribed range surrounding the point are sparsely distributed over a relatively wide range, a straight line angular variation evaluation value having a larger value; and

a vanishing point detecting unit that, using, as a vanishing point evaluation value, the straight line angular variation evaluation value, detects, as a vanishing point, a point at which the straight line angular variation evaluation value has a relatively large value in comparison with other points,

wherein a statistical value concerning the angles of the straight lines is used as the straight line angular variation evaluation value, wherein the statistical value concerning the angles of the straight lines includes at least one of;

variance, standard deviation, difference between maximum value and minimum value and ratio of maximum value and minimum value, of the angles of the straight lines.

10. A vanishing point detecting system comprising:

a straight line detecting unit that detects straight lines from an image and that assigns a confidence factor as a straight line to each of the straight lines detected;

a straight line angular variation evaluation value assigning unit that assigns, for each point in a space including at least a portion of the image, when angles of straight lines that pass through the point or through a prescribed range surrounding the point are sparsely distributed over a relatively wide range, a straight line angular variation evaluation value having a larger value;

a vanishing point evaluation value assigning unit that assigns a vanishing point evaluation value, for each point in a space including at least a portion of the image, the vanishing point evaluation value assigning unit when a relatively large number of straight lines pass, based on a confidence factor for straight lines passing through the point or through a prescribed range surrounding the point, assigning to the point the vanishing point evaluation value having a larger value; and

a vanishing point detecting unit that detects, as a vanishing point, a point at which the vanishing point evaluation value has a relatively large value;

wherein the vanishing point evaluation value assigning unit, when calculating the vanishing point evaluation value, takes into account the straight line angular variation evaluation value.

11. A vanishing point detecting method comprising:

detecting a straight line from an image;

assigning, for each point in a space including at least a portion of the image, when angles of straight lines that pass to the point or to a prescribed range surrounding the point are sparsely distributed over a relatively wide range, a straight line angular variation evaluation value having a larger value; and

using the straight line angular variation evaluation value as a vanishing point evaluation value, and detecting, as a vanishing point, a point at which the straight line angular variation evaluation value has a relatively large value.

12. The vanishing point detecting method according to claim 11, wherein in detecting a straight line from the image, the straight line is detected by a Hough transform, and a voting value of the Hough transform for the straight line is used as a confidence factor for the straight line.

13. The vanishing point detecting method according to claim 11, wherein a statistical value concerning the angles of the straight lines is used as the straight line angular variation evaluation value.

14. The vanishing point detecting method according to claim 11, wherein a confidence factor bias for the straight lines between a right bottom region and a left bottom region of a point in question is used as the straight line angular variation evaluation value.

15. The vanishing point detecting method according to claim 11, wherein image data obtained from an in-vehicle sensor is used as the image, and a vanishing point with regard to a lane marker representing a driving lane and/or a road edge is detected as the vanishing point.

16. A vehicle surrounding environment recognition method that calculates a positional relationship between a vehicle and surrounding environment, based on a position of the vanishing point obtained by the vanishing point detecting method according to claim 11.

17. The vehicle surrounding environment recognition method according to claim 16, wherein a pitch angle between a road surface and a direction in which the vehicle is heading is calculated, as a positional relationship of the vehicle and the surrounding environment.

18. A vanishing point detecting method comprising:

detecting a straight line from an image together with a confidence factor as a straight line;

assigning, for each point in a space including at least a portion of the image, when angles of straight lines that pass to the point or to a prescribed range surrounding the point are sparsely distributed over a relatively wide range, a straight line angular variation evaluation value having a larger value;

assigning, for each point in a space including at least a portion of the image, when a relatively large number of straight lines pass, based on a confidence factor for straight lines that pass to the point or to a prescribed range surrounding the point, a vanishing point evaluation value having a larger value; and

detecting, as a vanishing point, a point at which the vanishing point evaluation value has a relatively large value;

wherein, when calculating the vanishing point evaluation value, the straight line angular variation evaluation value is taken into account.

19. A vanishing point detecting method detecting a straight line from an image;

assigning, for each point in a space including at least a portion of the image, when angles of straight lines that pass to the point or to a prescribed range surrounding the point are sparsely distributed over a relatively wide range, a straight line angular variation evaluation value having a larger value; and

using the straight line angular variation evaluation value as a vanishing point evaluation value, and detecting, as a vanishing point, a point at which the straight line angular variation evaluation value has a relatively large value,

wherein a statistical value concerning the angles of the straight lines is used as the straight line angular variation evaluation value, wherein a statistical value concerning the angles of the straight lines includes at least one of;

variance, standard deviation, difference between maximum value and minimum value and ratio of maximum value and minimum value, of the angles of the straight lines.

20. A non-transitory computer readable medium with an executable program thereon, the program for causing a computer which detects a vanishing point to execute the processing comprising:

detecting a straight line from an image;

assigning, for each point in a space including at least a portion of the image, when angles of straight lines that pass to the point or to a prescribed range surrounding the point are sparsely distributed over a relatively wide range, a straight line angular variation evaluation value having a larger value; and

using the straight line angular variation evaluation value as a vanishing point evaluation value, and detecting, as a vanishing point, a point at which the straight line angular variation evaluation value has a relatively large value.

21. The non-transitory computer readable medium according to claim 20, the program causing the computer to execute the processing comprising:

detecting a straight line from an image together with a confidence factor as a straight line;

assigning, for each point in a space including at least a portion of the image, when angles of straight lines that pass to the point or to a prescribed range surrounding the point are sparsely distributed over a relatively wide range, a straight line angular variation evaluation value having a larger value;

assigning, for each point in a space including at least a portion of the image, a vanishing point evaluation value having a larger value than a case in which a relatively large number of straight lines pass, based on a confidence factor of straight lines that pass to the point or to a prescribed range surrounding the point, and at this occasion, of taking into account the straight line angular variation evaluation value, to calculate the vanishing point evaluation value; and

detecting, as a vanishing point, a point at which the vanishing point evaluation value has a relatively large value.

22. The non-transitory computer readable medium according to claim 20, wherein in the straight line detecting processing, a straight line is detected by a Hough transform, and a voting value of the Hough transform for the straight line is used as a confidence factor for the straight line.

23. The non-transitory computer readable medium according to claim 20, wherein a statistical value concerning the angles of the straight lines is used as the straight line angular variation evaluation value.

24. The non-transitory computer readable medium according to claim 20, wherein a confidence factor bias for the straight lines between a right bottom region and a left bottom region of a point in question is used as the straight line angular variation evaluation value.

25. The non-transitory computer readable medium according to claim 20, the program causing the computer to execute a processing comprising:

using data obtained from an in-vehicle sensor as the image, and of detecting a vanishing point, with regard to a lane marker representing a driving lane and/or a road edge, as the vanishing point.

26. The non-transitory computer readable medium according to claim 20, the program causing the computer to execute the processing comprising:

calculating a positional relationship of a vehicle and surrounding environment, based on a position of the vanishing point that has been derived, and performing recognition of the surrounding environment of the vehicle.

27. The non-transitory computer readable medium according to claim 24, causing the computer to execute the processing comprising:

calculating a pitch angle between a road surface and a direction in which a vehicle is headed, as a positional relationship of the vehicle and the surrounding environment.

28. A non-transitory computer readable medium with an executable program thereon, the program for causing a computer which detects a vanishing point to execute the processing comprising:

detecting a straight line from an image;

assigning, for each point in a space including at least a portion of the image, when angles of straight lines that pass to the point or to a prescribed range surrounding the point are sparsely distributed over a relatively wide range, a straight line angular variation evaluation value having a larger value; and

using the straight line angular variation evaluation value as a vanishing point evaluation value, and detecting, as a vanishing point, a point at which the straight line angular variation evaluation value has a relatively large value, wherein a statistical value concerning the angles of the straight lines is used as the straight line angular variation evaluation value,

wherein the statistical value concerning the angles of the straight lines includes at least one of;

variance, standard deviation, difference between maximum value and minimum value and ratio of maximum value and minimum value, of the angles of the straight lines.