Image processing apparatus

• US 20080024606A1
• Filed: 06/21/2007
• Published: 01/31/2008
• Est. Priority Date: 07/25/2006
• Status: Abandoned Application

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Kawasaki, Naoki
• Application Number:
  US11/821,120
• Publication Number:
  US 20080024606A1
• Time in Patent Office: Days
• US Class Current: 348/148
• CPC Class Codes: G03B 7/08 Control effected solely on the basis of the response, to the intensity of the light received by the camera, of a built-in light-sensitive device
• CPC Class Codes: G06V 10/141 Control of illumination
• 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: H04N 23/71 Circuitry for evaluating the brightness variation

Abstract

An image processing unit for use in a vehicle has a camera for capturing an image of a field around the vehicle, and the image captured by the camera is used to estimates an external environment of the vehicle. The external environment of the vehicle such as a luminance of the image and the like around the vehicle is estimated by using a camera control value and a pixel value of an imaging object based on a relationship that the pixel value of the imaging object captured by the camera is determined by the luminance of the imaging object and the camera control value.

Claims

1. A vehicle image processing apparatus comprising:

an onboard camera for capturing an image including an imaging object around a vehicle;

a camera control value setup unit configured for setting a camera control value of at least one of camera control parameters such as an onboard camera aperture, a shutter speed, and an output signal gain in accordance with an external environment for the vehicle during imaging;

an imaging object pixel value acquisition unit configured for acquiring a pixel value for the imaging object in the image captured by the onboard camera; and

an imaging object luminance estimation unit configured for estimating a luminance of the imaging object from the camera control value set by the camera control value setup unit and the pixel value for the imaging object acquired by the imaging object pixel value acquisition unit using a cause-effect relationship in which the pixel value for the imaging object in the image captured by the onboard camera is determined based on the luminance of the imaging object and the camera control value.

2. The vehicle image processing apparatus according to claim 1,

wherein the onboard camera captures a road around the vehicle as the imaging object, and

the imaging object luminance estimation unit estimates the luminance of the road surface.

3. The vehicle image processing apparatus according to claim 2 further comprising:

a lane divider recognition unit configured for recognizing a lane marking that exists in the image captured by the onboard camera with a road surface included therein,

wherein the imaging object luminance estimation unit estimates the luminance of the lane marking.

4. The vehicle image processing apparatus according to claim 1,

wherein the onboard camera captures a sky around the vehicle as the image including the imaging object, and

the imaging object luminance estimation unit estimates the luminance of the sky.

5. A vehicle image processing apparatus comprising:

an onboard camera configured for capturing an image including a road surface around a vehicle;

a camera control value setup unit configured for setting a camera control value of at least one of camera control parameters such as an onboard camera aperture, a shutter speed, and an output signal gain so as to provided a specified pixel value for the road surface in the image captured by the onboard camera; and

a road surface luminance estimation unit configured for estimating a luminance of the road surface from the camera control value using a cause-effect relationship in which the luminance of the road surface is determined based on the camera control value when the camera control value setup unit sets the camera control value so as to provide the specified pixel value for the road surface.

6. A vehicle image processing apparatus comprising:

an ambient illuminance acquisition unit configured for acquiring an illuminance around a vehicle;

an onboard camera configured for capturing an image including an imaging object around the vehicle;

an imaging object luminance acquisition unit configured for acquiring an imaging object luminance estimated at least based on a pixel value for the imaging object in the image captured by the onboard camera; and

an imaging object lightness estimation unit configured for estimating an imaging object lightness from the illuminance acquired by the ambient illuminance acquisition unit and the imaging object luminance using a cause-effect relationship in which the imaging object luminance is determined based on the illuminance around the vehicle and the imaging object lightness.

7. The vehicle image processing apparatus according to claim 6,

wherein the onboard camera captures a road around the vehicle as the image including the imaging object, and

the imaging object lightness estimation unit estimates the lightness of the road surface.

8. The vehicle image processing apparatus according to claim 7 further comprising:

a lane marking recognition unit configured for recognizing a lane marking that exists in the image captured by the onboard camera with a road surface included therein,

wherein the imaging object lightness estimation unit estimates the lightness of the lane marking.

9. The vehicle image processing apparatus according to claim 7 further comprising:

a lighting unit disposed on the vehicle and configured for emitting a light that lights around the vehicle,

wherein the imaging object lightness estimation unit estimates the lightness of the imaging object from the illuminance of the light emitted from the lighting unit, the illuminance acquired by the ambient illuminance acquisition unit, and the luminance of the imaging object based on a cause-effect relationship that the luminance of the imaging object is determined by the illuminance of the light emitted from the lighting unit, the illuminance around the vehicle, and the lightness of the imaging object when the lighting unit is being turned on.

10. A vehicle image processing apparatus comprising:

an onboard camera configured for capturing an image including a sky around a vehicle;

a sky luminance acquisition unit configured for acquiring a luminance of the sky around the vehicle at least based on a pixel value for the sky in the image captured by the onboard camera; and

an ambient illuminance estimation unit configured for acquiring an illuminance around the vehicle from the luminance of the sky acquired by the sky luminance acquisition unit using a cause-effect relationship in which the illuminance around the vehicle is determined based on the luminance of the sky around the vehicle.

11. A vehicle image processing apparatus comprising:

an onboard camera configured for capturing an image including an imaging object around a vehicle;

an imaging object luminance acquisition unit configured for acquiring an imaging object luminance at least based on a pixel value for the imaging object in the image captured by the onboard camera;

an imaging object lightness acquisition unit configured for acquiring a lightness of the imaging object around the vehicle; and

an ambient illuminance estimation unit configured for estimating an illuminance around the vehicle from the imaging object luminance acquired by the imaging object luminance acquisition unit and the imaging object lightness acquired by the imaging object lightness acquisition unit using a cause-effect relationship in which the luminance of an imaging object is determined based on the illuminance around the vehicle and the lightness of the imaging object.

12. The vehicle image processing apparatus according to claim 11,

wherein the onboard camera captures a road around the vehicle as the image including the imaging object,

the imaging object luminance acquisition unit acquires a road surface luminance based on the pixel value of a road surface of the image,

the imaging object lightness acquisition unit acquires a road surface lightness, and

the ambient illuminance estimation unit estimates the illuminance around the vehicle from the road surface luminance acquired by the imaging object luminance acquisition unit and the road surface lightness acquired by the imaging object lightness acquisition unit based on a cause-effect relationship that the road surface luminance is determined by the illuminance around the vehicle and the road surface lightness.

13. The vehicle image processing apparatus according to claim 12 further comprising:

a lane marking recognition unit configured for recognizing a lane marking that exists in the image captured by the onboard camera with a road surface included therein,

wherein the imaging object luminance acquisition unit acquires a lane marking luminance based on the pixel value of the lane marking in the image,

the imaging object lightness acquisition unit acquires a lane marking lightness, and

the ambient illuminance estimation unit estimates the illuminance around the vehicle from the lane marking luminance acquired by the imaging object luminance acquisition unit and the lane marking lightness acquired by the imaging object lightness acquisition unit based on a cause-effect relationship that the lane marking luminance is determined by the illuminance around the vehicle and the lane marking lightness.