System and method for detection and tracking of moving objects

Patent metadata

Field	Value
Publication number	US-9465997-B2
Application number	US-201213627629-A
Country	US
Kind code	B2
Filing date	Sep 26, 2012
Priority date	Sep 26, 2012
Publication date	Oct 11, 2016
Grant date	Oct 11, 2016

Abstract

A method implemented using a processor based device is disclosed. The method includes receiving a video stream comprising a plurality of image frames having at least one moving object, determining a difference between at least two image frames among the plurality of image frames and generating a difference image comprising a plurality of image blobs corresponding to the at least one moving object. The method further includes generating a plurality of bounding boxes, each bounding box surrounding at least one corresponding image blob among the plurality of image blobs, and determining a subset of bounding boxes among the plurality of bounding boxes, associated with the corresponding moving object, using a fuzzy technique based on a perceptual characterization of the subset of bounding boxes. The method also includes merging the subset of bounding boxes to generate a merged bounding box enclosing the subset of bounding boxes to detect the moving object.

First claim

What is claimed as new and desired to be protected by Letters Patent of the United States is:

1. A method implemented using a processor based device, comprising:
receiving a video stream comprising a plurality of image frames having at least one moving object;
determining a difference between at least two image frames among the plurality of image frames and generating a difference image comprising a plurality of image blobs corresponding to the at least one moving object;
generating a plurality of bounding boxes, each bounding box surrounding at least one corresponding image blob among the plurality of image blobs;
determining a subset of bounding boxes among the plurality of bounding boxes, associated with the corresponding moving object, using a fuzzy decision variable determined based on a motion cohesion fuzzy parameter, an appearance similarity fuzzy parameter, and a box affinity fuzzy parameter corresponding to each pair of bounding boxes among the subset of bounding boxes; and
merging the subset of bounding boxes to generate a merged bounding box enclosing the subset of bounding boxes to detect the moving object.

2. The method of claim 1 , wherein the box affinity fuzzy parameter for a pair of bounding boxes is based on a geometrical affinity of the pair of bounding boxes.

3. The method of claim 1 , wherein the motion cohesion fuzzy parameter for a pair of bounding boxes is based on a motion cohesion between the pair of bounding boxes.

4. The method of claim 1 , wherein the appearance similarity fuzzy parameter for a pair of bounding boxes is based on an appearance similarity between the pair of bounding boxes.

5. The method of claim 1 , wherein each of the motion cohesion fuzzy parameter, the appearance similarity fuzzy parameter, the box affinity fuzzy parameter, and merge fuzzy parameter comprises a corresponding linguistic variable determined based on a corresponding characterizing parameter and a corresponding membership function.

6. The method of claim 5 , wherein the corresponding membership function comprises a Gaussian function, or a sigmoid function.

7. The method of claim 1 , wherein merging the subset of bounding boxes is based on an agglomerative clustering algorithm.

8. The method of claim 7 , wherein merging the subset of bounding boxes comprises merging a pair of bounding boxes to generate the merged bounding box enclosing the pair of bounding boxes.

9. The method of claim 8 , further comprising determining an area of the merged bounding box, wherein merging the pair of bounding boxes is based on the determined area of the merged bounding box.

10. A system comprising:
a processor based device configured to:
receive from a video camera a video stream comprising a plurality of image frames having at least one moving object;
determine a difference between at least two image frames among the plurality of image frames to generate a difference image comprising a plurality of image blobs;
generate a plurality of bounding boxes, each bounding box surrounding at least one corresponding image blob among the plurality of image blobs;
determine a subset of bounding boxes among the plurality of bounding boxes, associated with the corresponding moving object, using a fuzzy decision variable determined based on a motion cohesion fuzzy parameter, an appearance similarity fuzzy parameter and a box affinity fuzzy parameter corresponding to each pair of bounding boxes among the subset of bounding boxes; and
merge the subset of bounding boxes to generate a merged bounding box enclosing the subset of bounding boxes to detect the moving object.

11. The system of claim 10 , wherein the processor based device is further configured to determine at least one of a geometric affinity, a motion cohesion and an appearance similarity corresponding to a pair of bounding boxes.

12. The system of claim 10 , wherein the processor based device is further configured to determine the fuzzy parameter comprising a linguistic variable determined based on a characterizing parameter and a membership function for each of the motion cohesion fuzzy parameter, the appearance similarity fuzzy parameter, the box affinity fuzzy parameter, and merge fuzzy parameter.

13. The system of claim 10 , wherein the processor based device is configured to merge a pair of bounding boxes among the subset of bounding boxes to generate a merged bounding box enclosing the pair of bounding boxes.

14. The system of claim 13 , wherein the processor based device is configured to determine an area of the merged bounding box, wherein the pair of bounding boxes is merged based on the determined area of the merged bounding box.

15. A non-transitory computer readable medium encoded with a program to instruct a processor based device to:
receive a video stream comprising a plurality of image frames having at least one moving object;
determine a difference between at least two image frames among the plurality of image frames to generate a difference image comprising a plurality of image blobs corresponding to the at least one moving object;
generate a plurality of bounding boxes, each bounding box surrounding at least one corresponding image blob among the plurality of image blobs;
determine a subset of bounding boxes among the plurality of bounding boxes, associated with the corresponding moving object, using a fuzzy decision variable determined based on a motion cohesion fuzzy parameter, an appearance similarity fuzzy parameter and a box affinity fuzzy parameter corresponding to each pair of bounding boxes among the subset of bounding boxes; and
merge the subset of bounding boxes to generate a merged bounding box enclosing the subset of bounding boxes to detect the moving object.

Assignees

• Gen Electric

Inventors

• Tu Jilin
• Xu Yi
• Del Amo Ana Isabel
• Sebastian Thomas Baby

Classifications

• G06T7/254 Primary

  involving subtraction of images · CPC title

• G06V10/809

  of classification results, e.g. where the classifiers operate on the same input data · CPC title

• G06V20/52 Primary

  Surveillance or monitoring of activities, e.g. for recognising suspicious objects (recognising microscopic objects G06V20/69) · CPC title

• G06F18/254

  of classification results, e.g. of results related to same input data · CPC title

• G06K9/00771 Primary

  Physics · mapped topic