Vehicle, image processing system image processing method, image processing program, method for configuring image processing system, and server

• US 20090041303A1
• Filed: 05/22/2006
• Published: 02/12/2009
• Est. Priority Date: 05/27/2005
• Status: Active Grant

• Current Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Original Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Inventors: Aoki, Tomoyoshi, Mori, Naoki, Kobayashi, Sachio, Nakamori, Takuma
• Granted Patent: US 8,135,175 B2
• Time in Patent Office: Days
• US Class Current: 382/104
• CPC Class Codes: G06T 7/73 using feature-based methods
• CPC Class Codes: G06V 10/255 Detecting or recognising potential candidate objects based on visual cues, e.g. shapes
• 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 processing system and the like capable of accurately recognizing lane edges defined by dotted lane marks are provided. According to an image processing system (100) of the present invention, a first processing unit (110) searches a road surface image captured by a vehicle-mounted camera for a “small area,” which is composed of high- or low-luminance pixels and satisfies “eligibility conditions” on the “size,” “shape,” and “arrangement” in the road surface image. Additionally, a second processing unit (120) recognizes “lane edges” of the lane along which the vehicle travels on the basis of the “small area.” Furthermore, a third processing unit (130) sets a “search range” of the small area searched by the first processing unit (110) on the basis of a result of the foregoing recognition of the lane edges by the second processing unit (120).

Claims

1. A vehicle equipped with:

an imaging means;

an image processing system which performs image processing on the basis of a road surface image captured by the imaging means; and

a vehicle running condition control system which controls a running condition of the vehicle on the basis of a result of the image processing performed by the image processing system,

wherein the image processing system includes;

a first processing unit which searches for a small area composed of high- or low-luminance pixels and satisfying eligibility conditions; and

a second processing unit which recognizes lane edges of a lane along which the vehicle travels on the basis of the small area found by the first processing unit; and

wherein the eligibility conditions are those on the size, the size and shape, the size and arrangement, or the size, shape, and arrangement in the road surface image.

2. A vehicle according to claim 1, further comprising a third processing unit which sets a search range of the small area searched by the first processing unit on the basis of a result of a previous search for the small area performed by the first processing unit, a result of previous recognition of the lane edges performed by the second processing unit, or standard arrangement information on dotted lane marks stored in a storage unit.

3. A vehicle according to claim 2, wherein the third processing unit sets the search range of the small area searched by the first processing unit on the basis of the standard arrangement information on the dotted lane marks stored in the storage unit if the small area is not previously found by the first processing unit or if the lane edges are not previously recognized by the second processing unit though the small area is previously found by the first processing unit.

4. A vehicle according to claim 1, further comprising a third processing unit which sets the search range of the small area searched by the first processing unit to be smaller than in the case of the small area not previously found by the first processing unit if the small area is previously found by the first processing unit or which sets the search range of the small area searched by the first processing unit to be smaller than in the case of the lane edges not previously recognized by the second processing unit if the lane edges are previously recognized by the second processing unit.

5. A vehicle according to claim 1, which is equipped with a speed sensor and a yaw rate sensor, further comprising a third processing unit which sets the search range of the small area searched by the first processing unit on the basis of one or both of a vehicle speed measured by the speed sensor and a vehicle yaw rate measured by the yaw rate sensor.

6. A vehicle according to claim 2, wherein the first processing unit sets one or both of a threshold value defining a high luminance level of a pixel and a threshold value defining a low luminance level of the pixel on the basis of a luminance average of pixels in the search range set by the third processing unit.

7. A vehicle according to claim 1, wherein the first processing unit performs one or both of a search for the small area composed of high-luminance pixels by performing a tophat filtering process and a search for the small area composed of low-luminance pixels by performing a bothat filtering process in the road surface image.

8. A vehicle according to claim 1, wherein the first processing unit corrects the eligibility conditions on the basis of a running speed of the vehicle and exposure time of the imaging means before searching for the small area satisfying the eligibility conditions.

9. A vehicle according to claim 1, wherein the first processing unit searches for only the small area composed of high-luminance pixels in the road surface image if the luminance average of a part or all of the pixels in the road surface image is equal to or lower than a night reference value.

10. A vehicle according to claim 1, wherein the second processing unit recognizes the outline of the dotted lane mark on the basis of the small area found by the first processing unit and a shading pattern of the dotted lane mark stored in the storage unit before recognizing the lane edge.

11. A vehicle according to claim 10, wherein the second processing unit preferentially recognizes a point close to the center of the vehicle traffic lane among points on the outline of the dotted lane mark as a part of the lane edge.

12. An image processing system comprising:

a first processing unit which searches for a small area composed of high- or low-luminance pixels and satisfying eligibility conditions in a road surface image captured by imaging means mounted on a vehicle; and

a second processing unit which recognizes lane edges of a lane along which the vehicle travels on the basis of the small area found by the first processing unit,

wherein the eligibility conditions are those on the size, the size and shape, the size and arrangement, or the size, shape, and arrangement in the road surface image.

13. An image processing system according to claim 12, further comprising a third processing unit which sets a search range of the small area searched by the first processing unit on the basis of a result of a previous search for the small area performed by the first processing unit, a result of previous recognition of the lane edges performed by the second processing unit, or standard arrangement information on dotted lane marks stored in a storage unit.

14. An image processing system according to claim 13, wherein the third processing unit sets the search range of the small area searched by the first processing unit on the basis of the standard arrangement information on the dotted lane marks stored in the storage unit if the small area is not previously found by the first processing unit or if the lane edges are not previously recognized by the second processing unit though the small area is previously found by the first processing unit.

15. An image processing system according to claim 12, further comprising a third processing unit which sets the search range of the small area searched by the first processing unit smaller than in the case of the small area not previously found by the first processing unit if the small area is previously found by the first processing unit or which sets the search range of the small area searched by the first processing unit to be smaller than in the case of the lane edges not previously recognized by the second processing unit if the lane edges are previously recognized by the second processing unit.

16. An image processing system according to claim 12, further comprising a third processing unit which sets the search range of the small area searched by the first processing unit on the basis of one or both of a vehicle speed measured by a speed sensor mounted on the vehicle and a vehicle yaw rate measured by a yaw rate sensor mounted on the vehicle.

17. An image processing system according to claim 13, wherein the first processing unit sets one or both of a threshold value defining a high luminance level of a pixel and a threshold value defining a low luminance level of the pixel on the basis of a luminance average of pixels in the search range set by the third processing unit.

18. An image processing system according to claim 12, wherein the first processing unit performs one or both of the search for the small area composed of high-luminance pixels by performing a tophat filtering process and the search for the small area composed of low-luminance pixels by performing a bothat filtering process in the road surface image.

19. An image processing system according to claim 12, wherein the first processing unit corrects the eligibility conditions on the basis of a running speed of the vehicle and exposure time of the imaging means before searching for the small area satisfying the eligibility conditions.

20. An image processing system according to claim 12, wherein the first processing unit searches for only the small area composed of high-luminance pixels in the road surface image if the luminance average of a part or all of the pixels in the road surface image is equal to or lower than a night reference value.

21. An image processing system according to claim 12, wherein the second processing unit recognizes the outline of the dotted lane mark on the basis of the small area found by the first processing unit and a shading pattern of the dotted lane mark stored in the storage unit before recognizing the lane edge.

22. An image processing system according to claim 21, wherein the second processing unit preferentially recognizes a point close to the center of a vehicle traffic lane among points on the outline of the dotted lane mark as a part of the lane edge.

25. A method of distributing or downloading a part or all of the image processing program according to claim 24 to an in-vehicle computer to configure the image processing system according to claim 12.

26. A server which performs the method according to claim 25.

23. An image processing method comprising:

a first process of searching for a small area composed of high- or low-luminance pixels and satisfying eligibility conditions in a road surface image captured by imaging means mounted on a vehicle; and

a second process of recognizing lane edges of a lane along which the vehicle travels on the basis of the small area found in the first process,

wherein the eligibility conditions are those on the size, the size and shape, the size and arrangement, or the size, shape, and arrangement in the road surface image.

24. An image processing program which gives a computer:

a first processing function of searching for a small area composed of high- or low-luminance pixels and satisfying eligibility conditions in a road surface image captured by imaging means mounted on a vehicle; and

a second processing function of recognizing lane edges of a lane along which the vehicle travels on the basis of the small area found by the first processing function,

wherein the eligibility conditions are those on the size, the size and shape, the size and arrangement, or the size, shape, and arrangement in the road surface image.