Image correction apparatus and image correction method

• US 20050225645A1
• Filed: 03/29/2005
• Published: 10/13/2005
• Est. Priority Date: 03/30/2004
• Status: Active Grant

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fuji Photo Film Co Limited (Fujifilm Holdings Corporation)
• Inventors: Kaku, Toshihiko
• Granted Patent: US 7,982,772 B2
• Time in Patent Office: Days
• US Class Current: 348/208.990
• CPC Class Codes: G06T 2207/20201 Motion blur correction
• CPC Class Codes: G06T 2207/30252 Vehicle exterior; Vicinity of vehicle
• CPC Class Codes: G06T 5/73 Deblurring; Sharpening
• CPC Class Codes: G06T 7/20 Analysis of motion motion estimation for coding, decoding, compressing or decompressing digital video signals H04N19/43, H04N19/51

Abstract

An image correction apparatus which corrects blurring generated by the traveling of a vehicle in the captured image, including: a camera which captures an image of front of a vehicle continuously; mobile vector calculation means of calculating a mobile vector in an image of each object based on a position of an object in each image continuously captured by the camera; and blurring correction means of correcting blurring of the image captured by the camera using the mobile vector calculated by the mobile vector calculation means.

Claims

1. An image correction apparatus, comprising:

a camera which captures an image of front of a vehicle continuously;

mobile vector calculation means of calculating a mobile vector in an image of each object based on a position of an object in each image continuously captured by said camera; and

blurring correction means of correcting blurring of the image captured by said camera using the mobile vector calculated by said mobile vector calculation means.

2. The image correction apparatus as claimed in claim 1, wherein said mobile vector calculation means calculates a vanishing point of an optical flow of the image captured by said camera, and corrects direction of the mobile vector assuming that the mobile vector of each object is radially oriented from the vanishing point.

3. The image correction apparatus as claimed in claim 2, wherein said mobile vector calculation means corrects length of the mobile vector based on a direction to which an object in each image continuously captured by said camera has been corrected.

4. The image correction apparatus as claimed in claim 1, further comprising:

distance measurement means of measuring distance from the vehicle to each object;

speed measurement means of measuring speed of the vehicle; and

optical flow calculation means of calculating a calculatory optical flow of each object based on speed measured by said speed measurement means and distance to each object measured by said distance measurement means, wherein

said mobile vector calculation means calculates a position of the object in a second image by calculating a position of the object, which is included in a first image, in a second image based on the optical flow calculated by said optical flow calculation means, and searching the same object in a region centering on the position.

5. The image correction apparatus as claimed in claim 4, further comprising:

steering angle measurement means of measuring steering angle of the vehicle; and

swing speed calculation means of calculating swing speed of the vehicle based on speed measured by said speed measurement means and steering angle measured by said steering angle measurement means, wherein

said optical flow calculation means calculates a calculatory optical flow of each object further based on the swing speed calculated by said swing speed calculation means.

6. The image correction apparatus as claimed in claim 1, wherein said blurring correction means corrects blurring by adding an image, which is obtained by differentiating an image in each object to a direction of the mobile vector, to an original image.

7. The image correction apparatus as claimed in claim 6, further comprising a display unit which displays an image, of which blurring has been corrected by said blurring correction means.

8. The image correction apparatus as claimed in claim 1, further comprising:

exposure time control means of controlling exposure time of said camera; and

acceleration measurement means of measuring acceleration of the vehicle;

wherein

the larger the acceleration of the vehicle measured by said acceleration measurement means is, the shorter said exposure time control means controls exposure time of said camera.

9. The image correction apparatus as claimed in claim 8, wherein

said acceleration measurement means further measures change of swing speed of the vehicle, and

the larger the change of swing speed of the vehicle measured by said acceleration measurement means is, the shorter said exposure time control means controls exposure time of said camera.

10. The image correction apparatus as claimed in claim 8, wherein

said acceleration measurement means measures at least one of an amount of stepping on an accelerator of the vehicle, an amount of stepping on a brake, and a steering angle of a steering, and

the larger at least one variation of an amount of stepping on the accelerator, an amount of stepping on the brake, and a steering angle of the steering wheel is, the shorter said exposure time control means controls the exposure time of said camera.

11. The image correction apparatus as claimed in claim 1, wherein said blurring correction means corrects blurring in the region near right side and left side of each of the images continuously captured by said camera more accurately than correction of blurring in a region near upper side and lower side of each of the images.

12. The image correction apparatus as claimed in claim 11, wherein said blurring correction means omits to correct blurring in a region near upper side and lower side of each of the images continuously captured by said camera.

13. The image correction apparatus as claimed in claim 1, wherein

said mobile vector calculation means calculates a vanishing point of an optical flow of the image captured by said camera, and

said blurring correction means corrects blurring in a region near the vanishing point of the optical flow less accurately than the other regions.

14. The image correction apparatus as claimed in claim 1, wherein

said blurring correction means corrects blurring in a central region of each of the images continuously captured by said camera less accurately than the other regions.

19. The image correction method as claimed in claim 4, further comprising:

a steering angle measurement step of measuring steering angle of the vehicle; and

a swing speed calculation step of calculating swing speed of the vehicle based on speed measured in said speed measurement step and steering angle measured in said steering angle measurement step, wherein

a calculatory optical flow of each object is calculated in said optical flow calculation step further based on the swing speed calculated in said swing speed calculation step.

15. An image correction method, comprising:

a step of capturing an image of front of a vehicle continuously by a camera;

a mobile vector calculation step of calculating a mobile vector in an image of each object based on a position of an object in each image continuously captured by the camera;

a blurring correction step of correcting blurring of the image captured by the camera using the mobile vector calculated in said mobile vector calculation step; and

a steering angle measurement step of measuring steering angle of the vehicle.

16. The image correction method as claimed in claim 15, wherein a vanishing point of an optical flow of the image captured by said camera is calculated in said mobile vector calculation step, and direction of the mobile vector is corrected assuming that the mobile vector of each object is radially oriented from the vanishing point.

17. The image correction method as claimed in claim 16, wherein length of the mobile vector is corrected in said mobile vector calculation step based on a direction to which an object in each image continuously captured by said camera has been corrected.

18. The image correction method as claimed in claim 15, further comprising:

a distance measurement step of measuring distance from the vehicle to each object;

a speed measurement step of measuring speed of the vehicle; and

an optical flow calculation step of calculating a calculatory optical flow of each object based on speed measured in said speed measurement step and distance to each object measured in said distance measurement step, wherein

a position of the object in a second image is calculated in said mobile vector calculation step by calculating a position of the object, which is included in a first image, in a second image based on the optical flow calculated in said optical flow calculation step, and searching the same object in a region centering on the position.

20. The image correction method as claimed in claim 15, wherein blurring is corrected in said blurring correction step by adding an image, which is obtained by differentiating an image in each object to a direction of the mobile vector, to an original image.

21. The image correction method as claimed in claim 20, further comprising a displaying step of displaying an image, of which blurring has been corrected in said blurring correction step.

22. The image correction method as claimed in claim 15, wherein blurring is corrected in said blurring correction step in the region near right side and left side of each of the images continuously captured by said camera more accurately than correction of blurring in a region near upper side and lower side of each of the images.

23. The image correction method as claimed in claim 22, wherein blurring correction is omitted in said blurring correction step in a region near upper side and lower side of each of the images continuously captured by said camera.

24. The image correction method as claimed in claim 15, wherein

a vanishing point of an optical flow of the image captured by said camera is calculated in said mobile vector calculation step, and

blurring is corrected in said blurring correction step in a region near the vanishing point of the optical flow less accurately than the other regions.

25. The image correction method as claimed in claim 15, wherein

blurring is corrected in said blurring correction steps in a central region of each of the images continuously captured by the camera less accurately than the other regions.