Method for obtaining a picture and multi-camera system

Patent metadata

Field	Value
Publication number	US-9866766-B2
Application number	US-201615147482-A
Country	US
Kind code	B2
Filing date	May 5, 2016
Priority date	Feb 18, 2014
Publication date	Jan 9, 2018
Grant date	Jan 9, 2018

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.

First claim

What is claimed is:

1. A method for obtaining a picture with a multi-camera system, the method comprising:
detecting a fast shooting mode condition;
capturing a first image with a first camera when the fast shooting mode condition is detected;
capturing a second image with a second camera when the fast shooting mode condition is detected;
evaluating a first sharpness of a first part of the first image;
evaluating a second sharpness of a second part of the second image;
setting a first exposure time for the first camera based on the first sharpness;
setting a second exposure time for the second camera based on the second sharpness;
capturing a third image with the first exposure time;
capturing a fourth image with the second exposure time; and
obtaining the picture based on the third image and the fourth image.

2. The method of claim 1 , wherein the first exposure time is set longer than the second exposure time, when the first image is less sharp than the second image.

3. The method of claim 1 , wherein evaluating the first sharpness and evaluating the second sharpness comprises iteratively measuring the first sharpness and the second sharpness.

4. The method of claim 1 , wherein the fast shooting mode condition comprises an autofocus process being incomplete.

5. The method of claim 1 , wherein the fast shooting mode condition comprises the multi-camera system is moving.

6. The method of claim 1 , wherein the fast shooting mode condition comprises an object of interest is moving relative to the multi-camera system.

7. The method of claim 1 , wherein the fast shooting mode condition comprises receiving a command for obtaining the picture being detected after a time period less than a predetermined threshold value, wherein the time period is measured from activating the multi-camera system.

8. A multi-camera apparatus for obtaining a picture, the multi-camera apparatus comprising:
a first camera;
a second camera;
a processor in communication with the first camera and the second camera; the processor configured to:
detect a fast shooting mode condition;
evaluate a first sharpness of a first part of a first image captured by the first camera when the fast shooting mode condition is detected;
evaluate a second sharpness of a second part of a second image captured by the second camera when the fast shooting mode condition is detected;
set a first exposure time for the first camera based on the first sharpness;
set a second exposure time for the second camera based on the second sharpness; and
obtain the picture based on a third image captured with the first exposure time and a fourth image captured with the second exposure time.

9. The multi-camera apparatus of claim 8 , wherein the first camera and the second camera comprise an overlapping field of view.

10. A non-transitory computer readable storage medium comprising program instructions that when executed by a processor of a multi-camera apparatus cause the multi-camera apparatus to:
detect a fast shooting mode condition;
evaluate a first sharpness of a first part of a first image captured by the first camera when the fast shooting mode condition is detected;
evaluate a second sharpness of a second part of a second image captured by the second camera when the fast shooting mode condition is detected;
set a first exposure time for the first camera based on the first sharpness;
set a second exposure time for the second camera based on the second sharpness; and
obtain the picture based on a third image captured with the first exposure time and a fourth image captured with the second exposure time.

Assignees

• Huawei Tech Co Ltd

Inventors

• Urfalioglu Onay
• Cordara Giovanni

Classifications

• H04N23/45 Primary

  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 title

• H04N23/73

  by influencing the exposure time · CPC title

• H04N23/667

  Camera operation mode switching, e.g. between still and video, sport and normal or high- and low-resolution modes · CPC title

• H04N23/951

  by using two or more images to influence resolution, frame rate or aspect ratio · CPC title

• H04N23/90 Primary

  Arrangement of cameras or camera modules, e.g. multiple cameras in TV studios or sports stadiums · CPC title