VEHICULAR IMAGE PROCESSING DEVICE AND VEHICULAR IMAGE PROCESSING PROGRAM

• US 20110019000A1
• Filed: 03/24/2009
• Published: 01/27/2011
• Est. Priority Date: 03/26/2008
• Status: Active Grant

• Current Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Original Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Inventors: Sakamoto, Yosuke
• Granted Patent: US 8,681,221 B2
• Time in Patent Office: Days
• US Class Current: 348/148
• CPC Class Codes: G06F 18/00 Pattern recognition
• CPC Class Codes: G06T 2207/10016 Video; Image sequence
• CPC Class Codes: G06T 2207/30256 Lane; Road marking
• CPC Class Codes: G06T 5/00 Image enhancement or restoration
• CPC Class Codes: G06T 5/002 Denoising; Smoothing noise processing or correction adapted to be used in an image pickup device containing and electronic image sensor H04N23/81, H04N25/60 - H04N25/67
• CPC Class Codes: G06T 5/70 Denoising; Smoothing
• CPC Class Codes: G06T 7/60 Analysis of geometric attributes
• 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

A vehicular image processing device is provided with a kernel setting unit which sets a plurality of smoothing kernels which have a width supposed to be between the width of the lane mark and that of the road to the image acquired from a photographing unit, a smoothing unit which smoothes the acquired image by filtering using the set smoothing kernels, a variation degree calculating unit which calculates the variation degree of the pixel value of each pixel in the acquired image with respect to the smoothed image, and a pixel value replacing unit which replaces the pixel value of a pixel which is of the acquired image and has the variation degree not greater than a predefined value with a specific value.

Claims

1. A vehicular image processing device configured to process an image acquired from a photographing unit mounted in a vehicle and detect a lane mark on a road where the vehicle is travelling from the processed image, comprising:

a kernel setting unit configured to set a kernel size for the image acquired from the photographing device so that the width of the kernel in a predefined direction is in a predefined range greater than the width of an image portion of the lane mark in the predefined direction;

a smoothing unit configured to smooth the acquired image according to a filtering process by the usage of the smoothing kernel size set by the kernel setting unit;

a variation degree calculating unit configured to calculate a variation degree of the pixel value of each pixel in the acquired image with respect to the smoothed image processed by the smoothing unit;

a pixel value replacing unit configured to replace the pixel value of the acquired image with a specific value if the variation degree is equal to or smaller than a predefined value; and

a lane mark detecting unit configured to detect the lane mark from the image with the pixel value replaced by the pixel value replacing unit.

2. The vehicular image processing device according to claim 1, wherein the specific value is a fixed value preliminarily defined.

3. The vehicular image processing device according to claim 1, wherein the specific value is the pixel value of a pixel in the smoothed image corresponded to the pixel in the acquired image.

4. The vehicular image processing device according to claim 1, wherein the kernel setting unit sets the kernel size in such a way that the kernel size for an image portion in the image corresponded to a predefined area on the road is set smaller as a distance from the vehicle to the predefined area on the road is becoming greater.

5. The vehicular image processing device according to claim 1, wherein the kernel setting unit sets the kernel to a rectangular shape or a trapezoidal shape.

6. The vehicular image processing device according to claim 5, wherein the kernel setting unit sets the direction of the kernel in such a way that the inclination of the center line of the long side of the kernel with respect to the direction corresponded to the travelling direction of the vehicle in the image is equal to a predefined angle.

7. The vehicular image processing device according to claim 1, wherein the variation degree calculating unit calculates a difference of pixel value of each pixel obtained by subtracting the pixel value of each pixel in the smoothed image from the pixel value of each pixel in the acquired image or a ratio of pixel value of each pixel obtained by dividing the pixel value of each pixel in the acquired image by the pixel value of each pixel in the smoothed image as the variation degree.

8. The vehicular image processing device according to claim 1, wherein luminance is used as the pixel value in the smoothed image processed by the smoothing unit.

9. The vehicular image processing device according to claim 1, wherein luminance or saturation calculated from color components of a color image is used as the pixel value in the smoothed image processed by the smoothing unit.

10. The vehicular image processing device according to claim 2, wherein the lane mark detecting unit detects an area composed of pixels of pixel value not equal to the fixed value in the replaced image by the pixel value replacing unit as an image portion corresponded to the lane mark on the road where the vehicle is travelling.

17. The vehicular image processing device according to claim 2, wherein the kernel setting unit sets the kernel size in such a way that the kernel size for an image portion in the image corresponded to a predefined area on the road is set smaller as a distance from the vehicle to the predefined area on the road is becoming greater.

18. The vehicular image processing device according to claim 2, wherein the kernel setting unit sets the kernel to a rectangular shape or a trapezoidal shape.

19. The vehicular image processing device according to claim 2, wherein the variation degree calculating unit calculates a difference of pixel value of each pixel obtained by subtracting the pixel value of each pixel in the smoothed image from the pixel value of each pixel in the acquired image or a ratio of pixel value of each pixel obtained by dividing the pixel value of each pixel in the acquired image by the pixel value of each pixel in the smoothed image as the variation degree.

20. The vehicular image processing device according to claim 2, wherein luminance is used as the pixel value in the smoothed image processed by the smoothing unit.

11. A vehicle which is provided with a photographing unit and has a function of processing an image acquired from the photographing unit and detecting a lane mark on a road where the vehicle is travelling, comprising:

a kernel setting unit configured to set a kernel size for the image acquired from the photographing device so that the width of the kernel in a predefined direction is in a predefined range greater than the width of an image portion of the lane mark in the predefined direction;

a smoothing unit configured to smooth the acquired image according to a filtering process by the usage of the smoothing kernel size set by the kernel setting unit;

a variation degree calculating unit configured to calculate a variation degree of the pixel value of each pixel in the acquired image with respect to the smoothed image processed by the smoothing unit;

a pixel value replacing unit configured to replace the pixel value of the acquired image with a specific value if the variation degree is equal to or smaller than a predefined value; and

a lane mark detecting unit configured to detect the lane mark from the image with the pixel value replaced by the pixel value replacing unit.

12. The vehicle according to claim 11, wherein the specific value is a fixed value preliminarily defined.

13. The vehicle according to claim 11, wherein the specific value is the pixel value of a pixel in the smoothed image corresponded to the pixel in the acquired image.

14. A vehicular image processing program configured to causing a computer to process an image acquired from a photographing unit mounted in a vehicle and detect a lane mark on a road where the vehicle is travelling from the processed image, and the computer being caused to execute:

a kernel setting process configured to set a kernel size for the image acquired from the photographing device so that the width of the kernel in a predefined direction is in a predefined range greater than the width of an image portion of the lane mark in the predefined direction;

a smoothing process configured to smooth the acquired image according to a filtering process by the usage of the smoothing kernel size set by the kernel setting process;

a variation degree calculating process configured to calculate a variation degree of the pixel value of each pixel between the acquired image and the image smoothed by the smoothing process;

a pixel value replacing process configured to replace the pixel value of the acquired image with a specific value if the variation degree is equal to or smaller than a predefined value; and

a lane mark detecting process configured to detect the lane mark from the image with the pixel value replaced by the pixel value replacing process.

15. The vehicular image processing program according to claim 14, wherein the specific value is a fixed value preliminarily defined.

16. The vehicular image processing program according to claim 14, wherein the specific value is the pixel value of a pixel in the smoothed image corresponded to the pixel in the acquired image.