Method and Device for Multi-Camera Image Correction

• US 20130113876A1
• Filed: 12/27/2012
• Published: 05/09/2013
• Est. Priority Date: 09/29/2010
• Status: Active Grant

• Current Assignee: Huawei Device Company Limited (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Huawei Device Company Limited (Huawei Investment & Holding Co., Ltd.)
• Inventors: ZHAO, Song, Liu, Yuan, Wang, Jing, Zhao, Guangyao
• Granted Patent: US 9,172,871 B2
• Time in Patent Office: Days
• US Class Current: 348/38
• CPC Class Codes: G06T 7/80 Analysis of captured images to determine intrinsic or extrinsic camera parameters, i.e. camera calibration
• CPC Class Codes: H04N 23/698 for achieving an enlarged field of view, e.g. panoramic image capture
• CPC Class Codes: H04N 7/15 Conference systems

Abstract

Embodiments of the present invention provide a method and a device for multi-camera image correction. The method for multi-camera image correction includes: acquiring information of independent images that are captured by each camera and have no overlap area or have an overlap area smaller than a threshold; acquiring, according to information of each independent image, an image correction parameter that corresponds to each camera and allows adjacent independent images to be corrected into a contiguous image; and performing, according to the image correction parameter, correction processing on video data of a camera that corresponds to the image correction parameter. In the embodiments of the present invention, maintenance manpower is saved, adjustment efficiency is improved, and remote maintenance may be performed in the case of no overlap area or of a small overlap area. In addition, images are corrected in a data processing manner, which efficiently ensures precision of image correction.

Claims

1. A method for multi-camera image correction, comprising:

acquiring information of independent images that are captured by each camera and have no overlap area or have an overlap area smaller than a threshold;

acquiring, according to information of each independent image, an image correction parameter that corresponds to each camera and allows adjacent independent images to be corrected into a contiguous image; and

performing, according to the image correction parameter, correction processing on video data of a camera that corresponds to the image correction parameter.

2. The method according to claim 1, wherein the acquiring information of the independent images that are captured by each camera and have no overlap area or have the overlap area smaller than the threshold comprises:

sending a capturing command to an image capturing system which each camera belongs to, and receiving information of independent images that are captured and sent by the image capturing system which each camera belongs to;

wherein the acquiring, according to the information of the independent images, the image correction parameter that corresponds to each camera comprises;

acquiring, according to the information of the independent images, at least one of a geometric correction parameter and a color correction parameter corresponding to each camera; and

the performing, according to the image correction parameter, the correction processing on the video data of the camera that corresponds to the image correction parameter comprises;

performing, according to at least one of the geometric correction parameter and the color correction parameter, the correction processing on the video data of the camera.

3. The method according to claim 2, wherein the acquiring, according to the information of the independent images, the geometric correction parameter corresponding to each camera comprises:

performing joint correction processing on the information of each independent image, acquiring information of each corrected image corresponding to the information of each independent image, wherein adjacent corrected images are contiguous, and acquiring each geometric correction parameter according to the information of each corrected image and information of a corresponding independent image.

4. The method according to claim 3, wherein the performing joint correction processing on the information of each independent image comprises:

selecting one image from the information of each independent image as base image information, and performing the correction processing on the base image information; and

using the base image information, which the correction processing has been performed on, as reference image information to perform the correction processing on information of each of other independent images.

5. The method according to claim 4, before the sending the capturing command to the image capturing system which each camera belongs to, further comprising:

sending the position adjustment instruction to each camera., so that each camera is aligned with each other.

6. The method according to claim 2, wherein the sending the capturing command to the image capturing system which each camera belongs to, and receiving the information of the independent images that are captured and sent by the image capturing system which each camera belongs to comprises:

sending, to the image capturing system which each camera belongs to, the capturing command for shooting template images, and receiving information of the template images exposed at a multiple exposure time, wherein the template images are captured and sent by each camera; and

the acquiring, according to the information of the independent images, the color correction parameter corresponding to each camera comprises;

acquiring, according to the information of the template images exposed at the multiple exposure time, a color correction parameter corresponding to each camera.

7. The method according to claim 6, wherein the acquiring, according to the information of the template images exposed at the multiple exposure time, the color correction parameter corresponding to each camera comprises:

acquiring levels of color component values of each adjacent image area between each camera in each exposure time according to the information of the template images exposed at the multiple exposure time;

performing interpolation processing on levels of pixel color component values of each image area in each exposure time to acquire a grading curve of pixel color component values of each camera in each exposure time; and

acquiring a color and brightness correction parameter of each camera according to a target curve and the grading curve of the pixel color component values.

8. The method according to claim 6, wherein the acquiring, according to the information of the template images exposed at the multiple exposure time, the color correction parameter corresponding to each camera comprises:

acquiring, according to the information of the template images exposed at the multiple exposure time, levels of color component values of adjacent image areas between multiple image partitions inside each camera in each exposure time;

performing interpolation processing on the levels of color component values of each image area in each exposure time to acquire a grading curve of color component values of each image partition in each exposure time; and

acquiring a color correction parameter of each image partition inside each camera according to a target curve and the grading curve of the color component values.

9. The method according to claim 7, wherein the target curve comprises one of the group consisting of:

(a) any curve among grading curves of the color component values, (b) an average curve of the grading curves of the color component values, and (c) a pixel reference distribution curve.

10. The method according to claim 8, wherein the target curse comprises one of the group consisting of:

(a) any curve among grading curves of the color component values, (b) an average curve of the grading curves of the color component values, and (c) a pixel reference distribution curve.

11. The method according to claim 6, wherein the performing correction processing on the video data of the corresponding camera according to the color correction parameter comprises:

determining a color look up table according to the color correction parameter, and performing the correction processing on the video data according to the color look up table.

12. The method according to claim 7, wherein the performing correction processing on the video data of the corresponding camera according to the color correction parameter comprises:

determining a color look up table according to the color correction parameter, and performing the correction processing on the video data according to the color look up table.

13. The method according to claim 8, wherein the performing correction processing on the video data of the corresponding camera according to the color correction parameter comprises:

determining a color look up table according to the color correction parameter, and performing the correction processing on the video data according to the color look up table.

14. A device for multi-camera image correction, comprising:

an acquiring module, configured to acquire information of independent images that are captured by each camera and have no overlap area or have an overlap area smaller than a threshold; and

acquire, according to information of each independent image, an image correction parameter that corresponds to each camera and allows adjacent independent images to be corrected into a contiguous image; and

a processing module, configured to perform, according to the image correction parameter acquired by the acquiring module, correction processing on video data of a camera that corresponds to the image correction parameter.

15. The device according to claim 14, wherein the acquiring module comprises:

a first acquiring unit, configured to send a capturing command to an image capturing system which each camera belongs to, and receive the information of the independent images that are captured and sent by the image capturing system which each camera belongs to;

a second acquiring unit, configured to acquire, according to the information of the independent images received by the first acquiring unit, at least one of a geometric correction parameter and a color correction parameter corresponding to each camera; and

the processing unit is configured to perform the correction processing on the video data of the corresponding camera according to at least one of the geometric correction parameter and color correction parameter acquired by the second acquiring unit.

16. The device according to claim 15, wherein the second acquiring unit is configured to perform joint correction processing on the information of each independent image, acquire information of each corrected image corresponding to the information of each independent image, wherein adjacent corrected images are contiguous, and acquire each geometric correction parameter according to the information of each corrected image and information of a corresponding independent image.

17. The device according to claim 15, wherein the first acquiring unit is configured to send, to an image capturing system which each camera belongs to, a capturing command for shooting template images, and receive information of the template images exposed at a multiple exposure time, wherein the template images are captured and sent by each camera;

and

the second acquiring module is configured to acquire levels of color component values of each adjacent image area between each camera in each exposure time according to the information of the template images exposed at the multiple exposure time;

perform interpolation processing on the levels of color component values of each image area in each exposure time to acquire a grading curve of color component values of each camera in each exposure time; and

acquire a color and brightness correction parameter of each camera according to a target curve and the grading curve of pixel color component values.

18. The device according to claim 15, wherein the first acquiring unit is configured to send, to an image capturing system which each camera belongs to, a capturing command for shooting template images, and receive information of the template images exposed at a multiple exposure time, wherein the template images are captured and sent by each camera;

and

the second acquiring module is configured to acquire, according to the information of the template images exposed at multiple exposure times, levels of color component values of adjacent image areas between multiple image partitions inside each camera in each exposure time;

perform interpolation processing on the levels of color component values of each image area in each exposure time to acquire a grading curve of color component values of each image partition in each exposure time; and

acquire a color correction parameter of each image partition inside each camera according to a target curve and the grading curve of color component values