Object detection using difference of image frames

• US 9,014,428 B2
• Filed: 02/15/2013
• Issued: 04/21/2015
• Est. Priority Date: 02/15/2013
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.), Sony Mobile Communications AB (Sony Group Corp.)
• Inventors: Hellman, Erik, Westenius, Erik
• Primary Examiner(s): Bitar, Nancy
• Application Number:
  US13/768,004
• Publication Number:
  US 20140233787A1
• Time in Patent Office: 795 Days
• Field of Search: None
• US Class Current: 382/103
• CPC Class Codes: G06V 20/46 Extracting features or characteristics from the video content, e.g. video fingerprints, representative shots or key frames
• CPC Class Codes: G06V 40/28 Recognition of hand or arm movements, e.g. recognition of deaf sign language static hand signs G06V40/113

Abstract

Object detection using a difference between image frames may include receiving a first image of a field of view, receiving a second image of the field of view, determining a difference between portions of the first image and corresponding portions of the second image, and declaring based on the difference between the portions of the first image and the corresponding portions of the second image that a specific object has been detected in the field of view.

Claims

1. An image capturing device for detection of features of animal beings based on involuntary movement, the image capturing device comprising:

a camera configured to obtain data representing a first image and a second image including a portion of an animal being in a field of view of the camera, wherein the first image and the second image are such that the animal being has not voluntarily moved between the obtaining of the first image and the obtaining of the second image; and

an object detector including;

a difference calculator configured to receive the data representing the first image and the second image and determine a difference between portions of the first image and corresponding portions of the second image even though the first image and the second image are such that the animal being did not voluntarily moved between the obtaining of the first image and the obtaining of the second image, the difference determined as larger than zero at least in part because of the involuntary movement, and

a classifier configured to declare, based on the difference between the portions of the first image and the corresponding portions of the second image, that a specific feature of the animal being has been detected in the field of view of the camera.

2. The image capturing device of claim 1, wherein

the difference calculator is configured to generate a difference image by performing a portion to portion comparison of the portions of the first image and the corresponding portions of the second image,

the difference image includes portions corresponding to the difference between the portions of the first image and the corresponding portions of the second image as determined by the comparison of the portions of the first image and the corresponding portions of the second image, and

the portions of the difference image are binarily set or unset based on a comparison of the difference between the portions of the first image and the corresponding portions of the second image and a threshold.

3. The image capturing device of claim 1, wherein the difference calculator is configured to perform a pixel by pixel comparison of pixels of the first image and corresponding pixels of the second image to determine difference between the pixels of the first image and the corresponding pixels of the second image.

4. The image capturing device of claim 3, wherein the difference calculator is configured to generate a difference image whose pixels correspond to the difference between the pixels of the first image and the corresponding pixels of the second image.

5. The image capturing device of claim 4, wherein the difference calculator is configured to binarily declare pixels of the difference image set or unset based on a comparison of the difference between the pixels of the first image and the corresponding pixels of the second image and a threshold.

6. The image capturing device of claim 4, comprising:

a data store including data corresponding to sample features of animal beings including the specific feature,

wherein the classifier is configured to compare features in the difference image to the sample features to declare that the specific feature has been detected in the field of view of the camera.

7. The image capturing device of claim 4, wherein the classifier is configured to perform an optical character recognition (OCR) of the difference image to recognize a pattern in the difference image corresponding to the specific feature.

8. A method for detection of features of animal beings based on involuntary movement, the method comprising:

receiving a first image including a portion of an animal being in a field of view;

receiving a second image including the portion of the animal being in the field of view, wherein the first image and the second image are such that the animal being did not voluntarily moved between the first image and the second image as captured;

determining difference between portions of the first image and corresponding portions of the second image even though the first image and the second image are such that the animal being did not voluntarily moved between the obtaining of the first image and the obtaining of the second image, the difference determined as larger than zero at least in part because of the involuntary movement; and

declaring based on the difference between the portions of the first image and the corresponding portions of the second image that a specific feature of the animal being has been detected in the field of view.

9. The method of claim 8, wherein the determining the difference between the portions of the first image and the corresponding portions of the second image includes:

performing a pixel by pixel comparison of pixels of the first image and corresponding pixels of the second image to determine difference between the pixels of the first image and the corresponding pixels of the second image.

10. The method of claim 9, wherein the determining the difference between the portions of the first image and the corresponding portions of the second image includes:

generating a difference image whose pixels correspond to the difference between the pixels of the first image and the corresponding pixels of the second image.

11. The method of claim 10, wherein the determining the difference between the portions of the first image and the corresponding portions of the second image includes:

binarily declaring pixels of the difference image set or unset based on a comparison of the difference between the pixels of the first image and the corresponding pixels of the second image and a threshold.

12. The method of claim 10, wherein the declaring based on the difference between the portions of the first image and the corresponding portions of the second image that the specific feature of the animal being has been detected includes:

comparing features in the difference image to predetermined sample features of animal beings.

13. The method of claim 10, wherein the declaring based on the difference between the portions of the first image and the corresponding portions of the second image that the specific feature of the animal being has been detected includes:

performing an optical character recognition (OCR) of the difference image to recognize a pattern in the difference image corresponding to the specific feature of the animal being.

14. The method of claim 8, wherein the determining the difference between the portions of the first image and the corresponding portions of the second image includes:

generating a difference image by performing a portion to portion comparison of the portions of the first image and the corresponding portions of the second image, wherein the difference image includes portions corresponding to the difference between the portions of the first image and the corresponding portions of the second image as determined by the comparison of the portions of the first image and the corresponding portions of the second image, and wherein the portions of the difference image are binarily set or unset based on a comparison of the difference between the portions of the first image and the corresponding portions of the second image and a threshold.

15. An object detector for detection of features of animal beings based on involuntary movement, comprising:

a processor;

a data store operatively connected to the processor and including data representing a first image and a second image including a portion of an animal being in a field of view, wherein the first image and the second image are such that the animal being did not voluntarily moved between the first image and the second image as captured;

a difference calculator configured to receive the data representing the first image and the second image and determine difference between portions of the first image and corresponding portions of the second image even though the first image and the second image reflect that the animal being did not voluntarily moved between the obtaining of the first image and the obtaining of the second image, the difference determined as larger than zero at least in part because of the involuntary movement; and

a classifier configured to declare, based on the difference between the portions of the first image and the corresponding portions of the second image, that a specific feature of the animal being has been detected in the field of view.

16. The object detector of claim 15, wherein

the difference calculator is configured to generate a difference image by performing a portion to portion comparison of the portions of the first image and the corresponding portions of the second image,

the difference image includes portions corresponding to the difference between the portions of the first image and the corresponding portions of the second image as determined by the comparison of the portions of the first image and the corresponding portions of the second image, and

the portions of the difference image are binarily set or unset based on a comparison of the difference between the portions of the first image and the corresponding portions of the second image and a threshold.

17. The object detector of claim 15, wherein

the difference calculator is configured to:

perform a pixel by pixel comparison of pixels of the first image and corresponding pixels of the second image to determine difference between the pixels of the first image and the corresponding pixels of the second image, and

binarily declaring pixels of a difference image set or unset based on a comparison of the difference between the pixels of the first image and the corresponding pixels of the second image and a threshold, and

the classifier is configured to;

compare features in the difference image to predetermined sample features to declare that the specific feature of the animal being has been detected in the field of view.