Method for Obtaining a Picture and Multi-Camera System

• US 20160248988A1
• Filed: 05/05/2016
• Published: 08/25/2016
• Est. Priority Date: 02/18/2014
• Status: Active Grant

• Current Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Inventors: Urfalioglu, Onay, Cordara, Giovanni
• Granted Patent: US 9,866,766 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06T 2207/20021 Dividing image into blocks, subimages or windows
• CPC Class Codes: G06T 2207/30168 Image quality inspection
• CPC Class Codes: G06T 7/00 Image analysis
• CPC Class Codes: H04N 23/45 for generating image signals from two or more image sensors being of different type or operating in different modes, e.g. with a CMOS sensor for moving images in combination with a charge-coupled device [CCD] for still images
• CPC Class Codes: H04N 23/60 Control of cameras or camera modules
• CPC Class Codes: H04N 23/667 Camera operation mode switching, e.g. between still and video, sport and normal or high- and low-resolution modes
• CPC Class Codes: H04N 23/73 by influencing the exposure time
• CPC Class Codes: H04N 23/90 Arrangement of cameras or camera modules, e.g. multiple cameras in TV studios or sports stadiums
• CPC Class Codes: H04N 23/951 by using two or more images to influence resolution, frame rate or aspect ratio

Abstract

A method and a multi-camera system for obtaining pictures with improved image quality. At least two cameras are used for each capturing an image, and a fast shooting mode is employed. The fast shooting mode may work in a preprocessing mode, in which the captured image of highest sharpness is acquired as a final picture, or may work in a post processing mode, in which multiple captured images are acquired, and are then post-processed to obtain a final picture of high image quality. In both modes it may be automatically determined, whether to activate the fast shooting mode or not. The determination is based on a relative movement of the multi-camera system to an object of interest, or is based on a shooting behavior of the user.

Claims

1. A method for obtaining a picture with a multi-camera system, comprising:

detecting a fast shooting mode condition;

controlling at least two cameras each for capturing an image when a fast shooting mode condition is detected; and

obtaining the picture based on the at least two captured images.

2. The method according to claim 1, further comprising:

evaluating sharpness in at least a part of each of the at least two captured images; and

acquiring the captured image having the highest sharpness to obtain the picture.

3. The method according to claim 2, further comprising adjusting a lens of at least one camera before acquiring the captured image based on the result of evaluating the sharpness in at least the part of the image captured by the at least one camera.

4. The method according to claim 1, further comprising:

acquiring at least two captured images; and

post-processing the at least two acquired images to obtain the picture.

5. The method according to claim 4, further comprising:

evaluating the sharpness in at least a part of each of the at least two captured images;

setting different exposure times for the at least two cameras according to a result of evaluating the sharpness; and

acquiring with each camera the captured image based on the set exposure time of said camera.

6. The method according to claim 5, wherein during setting the different exposure times, the exposure time for a camera capturing an image with lower sharpness is set longer than the exposure time for a camera capturing an image with higher sharpness.

7. The method according to claim 2, wherein evaluating the sharpness comprises iteratively measuring the sharpness in a salient region of each of the captured images.

8. The method according to claim 1, wherein controlling the at least two cameras comprises regulating independently lens positions of the at least two cameras.

9. The method according to claim 1, wherein the fast shooting mode condition is detected when an autofocus process is incomplete for each of the at least two cameras.

10. The method according to claim 1, wherein the fast shooting mode condition is detected when the multi-camera system is moving.

11. The method according to claim 1, wherein the fast shooting mode condition is detected when an object of interest in at least one of the captured images is moving relative to the multi-camera system.

12. The method according to claim 1, wherein a fast shooting mode is detected when a command for obtaining the picture is detected after a time period less than a predetermined threshold value, wherein the time period is measured from activating the multi-camera system.

13. A multi-camera system for obtaining a picture, comprising:

a detecting unit for detecting a fast shooting mode condition;

at least two cameras each for capturing an image; and

an image control unit for controlling the at least two cameras to obtain the picture based on the at least two captured images when a fast shooting mode condition is detected.

14. The multi-camera system according to claim 13, further comprising a sharpness detecting unit for evaluating sharpness in at least a part of each of the at least two captured images.

15. The multi-camera system according to claim 13, wherein the at least two cameras have an overlapping field of view.

16. A computer program having a program code for performing a method on a computer, the method comprising:

detecting a fast shooting mode condition;

controlling at least two cameras each for capturing an image when a fast shooting mode condition is detected; and

obtaining a picture based on the at least two captured images.