METHOD AND APPARATUS FOR CAMERA SHAKE EFFECT IMAGE STABILIZATION

• US 20090086036A1
• Filed: 09/27/2007
• Published: 04/02/2009
• Est. Priority Date: 09/27/2007
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: ATI Technologies ULC (Advanced Micro Devices, Inc.)
• Inventors: Aleksic, Milivoje, Safaee-Rad, Reza
• Granted Patent: US 9,179,060 B2
• Time in Patent Office: Days
• US Class Current: 348/208.600
• CPC Class Codes: H04N 1/2145 of a sequence of images for selection of a single frame before final recording, e.g. from a continuous sequence captured before and after shutter-release
• CPC Class Codes: H04N 23/54 Mounting of pick-up tubes, electronic image sensors, deviation or focusing coils
• CPC Class Codes: H04N 23/57 Mechanical or electrical details of cameras or camera modules specially adapted for being embedded in other devices
• CPC Class Codes: H04N 23/63 by using electronic viewfinders
• CPC Class Codes: H04N 23/64 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 Class Codes: H04N 23/673 based on contrast or high frequency components of image signals, e.g. hill climbing method

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.

Claims

1. A method for camera shake effect image stabilization, comprising:

determining image sharpness metric information for each image of a set of images that were captured at a same lens position; and

selecting a final image from the set as a stabilized image based on most favorable image sharpness metric information.

2. The method of claim 1, wherein selecting the final image is comprised of:

comparing two image sharpness metric informations associated with two images in the set and determining the most favorable image sharpness metric information between the two images; and

storing the most favorable image sharpness metric information and the associated image.

3. The method of claim 1, further comprising:

if the determining of the image sharpness metric information is performed on a first image of the set, then store 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.

4. The method of claim 1 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 camera shake effect image stabilization, comprising:

capturing a set of images during a camera shake condition after a camera lens has been focused;

reusing auto-focus image statistics logic to determine an image sharpness metric information for each image of the set; and

selecting a final image from the set as a stabilized image based on a most favorable image sharpness metric.

6. The method of claim 5, wherein selecting the final image is comprised of:

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 store 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 for camera shake effect image stabilization, comprising:

image capturing logic operative to capture a set of images during a camera shake condition after a camera lens has been focused;

an image sharpness metric circuit operative to determine image sharpness metrics for each image of the set of images;

memory operative to store the captured images and associated image sharpness metrics from the image sharpness metric circuit; and

image stabilization logic operative to select a final image from the set as a stabilized image based on a most favorable image sharpness metric.

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 for camera shake effect image stabilization comprising:

an image sharpness metric circuit operative to determine image sharpness metrics for each image of a set of images that were captured at a same lens position;

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 from the set as a stabilized image based on a most favorable image sharpness metric; and

a display operative to display the stabilized image.

14. The apparatus of claim 13, wherein the apparatus is a handheld device and comprises radio telephone subsystem.

15. The apparatus of claim 13, 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.

16. The apparatus of claim 13, 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.

17. The apparatus of claim 13, 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.

18. The apparatus of claim 13 comprising image capturing logic operative to capture the set of images during a camera shake condition.