Image processor for automotive vehicle

• US 20060233425A1
• Filed: 04/12/2006
• Published: 10/19/2006
• Est. Priority Date: 04/15/2005
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Kobayashi, Kenji, Tamatsu, Yukimasa
• Granted Patent: US 7,646,890 B2
• Time in Patent Office: Days
• US Class Current: 382/106
• CPC Class Codes: B60W 2420/403 Image sensing, e.g. optical camera
• CPC Class Codes: B60W 2420/42 Image sensing, e.g. optical camera
• CPC Class Codes: B60W 2554/00 Input parameters relating to objects
• CPC Class Codes: B60W 2556/50 of positioning data, e.g. GPS [Global Positioning System] data
• CPC Class Codes: B60W 50/14 Means for informing the driver, warning the driver or prompting a driver intervention
• 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

Abstract

An image processor for an automotive vehicle includes: an imaging element for capturing an image of a road; a traffic lane line detection element for detecting a position of a traffic lane line by determining an edge of the traffic lane line; a distance distribution calculation element for calculating a distance distribution of an edge intensity corresponding to a distance to the traffic lane line from the imaging element; and a detection reliability calculation element for calculating a degree of reliability of detection of the traffic lane line on the basis of the distance distribution of the edge intensity of the traffic lane line.

Claims

1. An image processor for an automotive vehicle comprising:

an imaging element for capturing an image of a road, on which the automotive vehicle is located;

a traffic lane line detection element for detecting a position of a traffic lane line on the road by determining an edge of the traffic lane line on the basis of the image of the road;

a distance distribution calculation element for calculating a distance distribution of an edge intensity of the traffic lane line, the distance distribution corresponding to a distance to the traffic lane line from the imaging element; and

a detection reliability calculation element for calculating a degree of reliability of detection of the traffic lane line on the basis of the distance distribution of the edge intensity of the traffic lane line.

2. The image processor according to claim 1, wherein

the detection reliability calculation element includes a detectable edge distance calculation element for calculating a detectable edge distance to the traffic lane line from the imaging element,

the detectable edge distance is defined as a distance, at which the edge intensity in the distance distribution shows a certain change, and

the detection reliability calculation element determines the degree of reliability of detection of the traffic lane line on the basis of a length of the detectable edge distance.

3. The image processor according to claim 2, wherein

the detectable edge distance calculation element determines the detectable edge distance, at which the edge intensity is equal to or smaller than a threshold edge intensity, and

the threshold edge intensity is determined on the basis of a maximum edge intensity in the distance distribution of the edge intensity.

4. The image processor according to claim 3, wherein

the threshold edge intensity is a half of the maximum edge intensity.

5. The image processor according to claim 2, wherein

the detectable edge distance calculation element determines the detectable edge distance, at which a degree of change of the edge intensity with respect to the distance is equal to or larger than a threshold degree of change of the edge intensity, and

the threshold degree of change of the edge intensity is preliminarily determined and memorized in the detectable edge distance calculation element.

6. The image processor according to claim 2, wherein

the degree of reliability of detection of the traffic lane line is proportional to the length of the detectable edge distance.

7. The image processor according to claim 1, further comprising:

a driving support element for performing a driving support on the basis of the degree of reliability of detection of the traffic lane line determined by the detection reliability calculation element.

8. The image processor according to claim 1, wherein

the traffic lane line detection element calculates the edge intensity in such a manner that the image of the road is differentiated along with a horizontal direction of the image in order to specify the edge of the traffic lane line.

9. An image processor for an automotive vehicle comprising:

an imaging element for imaging a road, on which the automotive vehicle is disposed;

a traffic lane line detection element for detecting a position of a traffic lane line on the road by determining an edge of the traffic lane line on the basis of an image of the road;

a distance distribution calculation element for calculating a distance distribution of a number of edge detection times of the traffic lane line detected by the traffic lane line detection element, the distance distribution corresponding to a distance to the traffic lane line from the imaging element; and

a detection reliability calculation element for calculating a degree of reliability of detection of the traffic lane line on the basis of the distance distribution of the number of edge detection times.

10. The image processor according to claim 9, wherein

the detection reliability calculation element includes a detectable edge distance calculation element for calculating a detectable edge distance to the traffic lane line from the imaging element,

the detectable edge distance is defined as a distance, at which the number of edge detection times in the distance distribution shows a certain change, and

the detection reliability calculation element determines the degree of reliability of detection of the traffic lane line on the basis of a length of the detectable edge distance.

11. The image processor according to claim 10, wherein

the detectable edge distance calculation element determines the detectable edge distance, at which the number of edge detection times is equal to or smaller than a threshold number of edge detection times, and

the threshold number of edge detection times is determined on the basis of a maximum number of edge detection times in the distance distribution of the number of edge detection times.

12. The image processor according to claim 11, wherein

the threshold number of edge detection times is a half of the maximum number of edge detection times.

13. The image processor according to claim 10, wherein

the detectable edge distance calculation element determines the detectable edge distance, at which a degree of change of the number of edge detection times with respect to the distance is equal to or larger than a threshold degree of change of the number of edge detection times, and

the threshold degree of change of the number of edge detection times is preliminarily determined and memorized in the detectable edge distance calculation element.

14. The image processor according to claim 10, wherein

the degree of reliability of detection of the traffic lane line is proportional to the length of the detectable edge distance.

15. The image processor according to claim 9, further comprising:

a driving support element for performing a driving support on the basis of the degree of reliability of detection of the traffic lane line determined by the detection reliability calculation element.

16. The image processor according to claim 9, wherein

the traffic lane line detection element detects the edge of the traffic lane line in such a manner that the image of the road is differentiated along with a horizontal direction of the image in order to specify the edge of the traffic lane line.

17. The image processor according to claim 9, wherein

the traffic lane line detection element counts the number of edge detection times of the traffic lane line by detecting the edge of the traffic lane line during a predetermined period.