Method and apparatus for camera shake effect image stabilization

Patent metadata

Field	Value
Publication number	US-9179060-B2
Application number	US-86262107-A
Country	US
Kind code	B2
Filing date	Sep 27, 2007
Priority date	Sep 27, 2007
Publication date	Nov 3, 2015
Grant date	Nov 3, 2015

Abstract

A method and apparatus for camera shake effect image stabilization determines a most favorable image sharpness metric out of image sharpness metrics from a plurality of images that were captured at a same lens position. A final image is selected based on the most favorable image sharpness metric.

First claim

What is claimed is:

1. A method for storing a stabilized image, comprising:
autofocusing a lens through a series of lens positions until a final lens position is determined;
determining image sharpness metric information for a set of images captured at the final lens position by calculating a sharpness metric value for each pixel in a plurality of regions of interest in the set of images, wherein each region of interest comprises a plurality of adjacent pixels, wherein each pixel comprises information captured from the lens;
selecting a final image frame from the set as the stabilized image based on the most favorable image sharpness metric information;
encoding the final image frame to create an encoded final image frame;
processing at least one image frame from the set for display before encoding the final image frame;
displaying the at least one image frame to a display; and
storing the encoded final image frame in a memory linked to a camera.

2. The method of claim 1 , wherein selecting the final image frame includes:
comparing two image sharpness metric informations associated with two image frames in the set and determining the most favorable image sharpness metric information between the two image frames.

3. The method of claim 1 , further comprising:
if the determining of the image sharpness metric information is performed on a first image frame of the set, then storing the image frame and associated image sharpness metric information as a most favorable image sharpness metric;
comparing a next image sharpness metric information of the set to the most favorable image sharpness metric information and determining a new most favorable image sharpness metric;
updating the most favorable image sharpness metric information and the next image sharpness metric; and
comparing each updated next sharpness metric information of the set to each updated most favorable image sharpness metric information until the set is empty.

4. The method of claim 1 , further comprising capturing the set of images during a camera shake condition, and wherein a quantity of images in the set to be compared is determined by a user.

5. A method for selecting a stabilized image, comprising:
autofocusing a lens through a series of lens positions until a final lens position is determined, based at least in part, on auto-focus image statistics logic;
capturing a set of images during a camera shake condition at the final lens position;
dividing each image of the set into a plurality of regions of interest, wherein each region of interest comprises a plurality of adjacent pixels;
determine an image sharpness metric information for each image of the set by performing statistical analysis on each region of interest, based on at least in part, on the auto-focus image statistics logic, by calculating a sharpness metric value for each pixel in the plurality of regions of interest in the set of images, wherein each pixel comprises information captured from the lens; and
selecting a final image from the set as the stabilized image based on a most favorable image sharpness metric.

6. The method of claim 5 , wherein selecting the final image includes:
comparing two image sharpness metrics associated with two images in the set and determining a most favorable image sharpness metric information between the two images; and
storing the most favorable image sharpness metric information and the associated image.

7. The method of claim 5 , further comprising:
if the determining of the image sharpness metric information is performed on a first image of the set, then storing the image and associated image sharpness metric information as a most favorable image sharpness metric;
comparing a next image sharpness metric information of the set to the most favorable image sharpness metric information and determining a new most favorable image sharpness metric;
updating the most favorable image sharpness metric information and the next image sharpness metric;
comparing each updated next sharpness metric information of the set to each updated most favorable image sharpness metric information until the set is empty; and
storing the image associated with a final most favorable image sharpness metric information as a stabilized image.

8. The method of claim 5 , wherein a quantity of images in the set to be compared is determined by a user.

9. A circuit in a camera for selecting a stabilized image, comprising:
autofocusing logic operative to autofocus a lens through a series of lens positions until a final lens position is determined;
image capturing logic operative to capture a set of images during a camera shake condition at the final lens position;
an image sharpness metric circuit operative to determine image sharpness metrics for each image frame of the set of images by calculating a sharpness metric value for each pixel in a plurality of regions of interest in the set of images, wherein each region of interest comprises a plurality of adjacent pixels, wherein each pixel comprises information captured from the lens;
memory operative to store the captured images and associated image sharpness metrics from the image sharpness metric circuit;
image stabilization logic operative to select a final image frame from the set as the stabilized image based on a most favorable image sharpness metric;
encoding logic operative to encode the final image frame as a final encoded image frame; and
processing logic operative to process at least one image frame from the set for display before the encoding logic encodes the final image frame, wherein the at least one image frame is displayed to a display.

10. The circuit in claim 9 , wherein a first address in the memory is operative to store a new image sharpness metric information and a new associated image from the image sharpness metric circuit and a second address in the memory is operative to store a current most favorable image sharpness metric information and an associated image.

11. The circuit in claim 9 , wherein the image stabilization logic, comprises:
comparator logic operative to compare the image sharpness metrics stored in the first and second addresses in memory; and
decision logic operative to output a signal indicating which address in memory contains the most favorable image sharpness metric.

12. The circuit in claim 9 , wherein the image sharpness metric circuit, comprises a statistical block operative to analyze image pixel information of an image and generate a statistical image sharpness metric information from the image pixel information.

13. An apparatus in a camera for selecting a stabilized image comprising:
autofocusing logic operative to autofocus a lens through a series of lens positions until a final lens position is determined;
an image sharpness metric circuit operative to determine image sharpness metrics for each image frame of a set of images that were captured at the final lens position by calculating a sharpness metric value for each pixel in a plurality of regions of interest in the set of images, wherein each region of interest comprises a plurality of adjacent pixels, wherein each pixel comprises information captured from the lens;
memory operative to store the captured images and associated image sharpness metrics from the image sharpness metric circuit;
image stabilization logic operative to select a final image frame from the set as the stabilized image based on a most favorable image sharpness metric;
a display operative to display the stabilized image frame;
encoding logic operative to encode the final image frame as a final encoded image frame; and
processing logic operative to proc

Assignees

• Safaee-Rad Reza
• Aleksic Milivoje
• Qualcomm Inc

Inventors

• Safaee-Rad Reza
• Aleksic Milivoje

Classifications

• H04N23/64 Primary

  Computer-aided capture of images, e.g. transfer from script file into camera, check of taken image quality, advice or proposal for image composition or decision on when to take image · CPC title

• H04N23/57

  Mechanical or electrical details of cameras or camera modules specially adapted for being embedded in other devices · CPC title

• H04N23/63

  by using electronic viewfinders · CPC title

• H04N23/673

  based on contrast or high frequency components of image signals, e.g. hill climbing method · CPC title

• H04N23/54 Primary

  Mounting of pick-up tubes, electronic image sensors, deviation or focusing coils · CPC title