Method and apparatus for modeling behavior using a probability distrubution function

• US 20030059081A1
• Filed: 06/28/2002
• Published: 03/27/2003
• Est. Priority Date: 09/27/2001
• Status: Active Grant

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Trajkovic, Miroslav
• Granted Patent: US 7,202,791 B2
• Time in Patent Office: Days
• US Class Current: 382/100
• CPC Class Codes: G06F 18/23 Clustering techniques
• CPC Class Codes: G06T 7/20 Analysis of motion motion estimation for coding, decoding, compressing or decompressing digital video signals H04N19/43, H04N19/51
• CPC Class Codes: G06V 10/762 using clustering, e.g. of similar faces in social networks
• CPC Class Codes: G06V 20/52 Surveillance or monitoring of activities, e.g. for recognising suspicious objects recognising microscopic objects G06V20/69
• CPC Class Codes: G06V 40/20 Movements or behaviour, e.g. gesture recognition recognition of facial expressions G06V40/16
• CPC Class Codes: G08B 13/19602 Image analysis to detect motion of the intruder, e.g. by frame subtraction
• CPC Class Codes: G08B 13/19613 Recognition of a predetermined image pattern or behaviour pattern indicating theft or intrusion
• CPC Class Codes: G08B 13/19615 wherein said pattern is defined by the user
• CPC Class Codes: G08B 13/19671 Addition of non-video data, i.e. metadata, to video stream
• CPC Class Codes: G08B 13/19673 Addition of time stamp, i.e. time metadata, to video stream
• CPC Class Codes: G08B 21/0423 detecting deviation from an expected pattern of behaviour or schedule
• CPC Class Codes: G08B 21/0476 Cameras to detect unsafe condition, e.g. video cameras
• CPC Class Codes: H04N 7/181 for receiving images from a plurality of remote sources

Abstract

A method and apparatus are disclosed for modeling patterns of behavior of humans or other animate objects and detecting a violation of a repetitive pattern of behavior. The behavior of one or more persons is observed over time and features of the behavior are recorded in a multi-dimensional space. Over time, the multi-dimensional data provides an indication of patterns of human behavior. Activities that are repetitive in terms of time, location and activity, such as sleeping and eating, would appear as a Gaussian distribution or cluster in the multi-dimensional data. Probability distribution functions can be analyzed using known Gaussian or clustering techniques to identify repetitive patterns of behavior and characteristics thereof, such as a mean and variance. Deviations from repetitive patterns of behavior can be detected and an alarm can be triggered, if appropriate.

Claims

1. A method for modeling behavior of an animate object, said method comprising the steps of:

obtaining a plurality of images;

extracting a plurality of features from said plurality of images; and

analyzing said plurality of extracted features in a multi-dimensional space.

2. The method of claim 1, wherein said multi-dimensional space provides a probability distribution function of said image data.

3. The method of claim 1, further comprising the step of clustering said extracted feature data to identify at least one repetitive pattern of behavior.

4. The method of claim 3, wherein said clustering step further comprises the step of computing a mean and variance of each cluster.

5. The method of claim 3, wherein a cluster of data corresponds to a pattern of behavior.

6. The method of claim 1, further comprising the step of fitting said extracted feature data to a probability distribution function to identify at least one Gaussian having a mean and a variance.

7. The method of claim 6, wherein a Gaussian corresponds to a pattern of behavior.

8. The method of claim 1, wherein said extracted feature data includes an indication of time.

9. The method of claim 1, wherein said extracted feature data includes an indication of location.

10. The method of claim 1, wherein said extracted feature data includes an indication of activity.

11. The method of claim 1, wherein said extracted feature data includes an indication of body posture.

12. A system for modeling behavior of an animate object, said system comprising:

a memory that stores computer-readable code; and

a processor operatively coupled to said memory, said processor configured to implement said computer-readable code, said computer-readable code configured to;

obtain a plurality of images;

extract a plurality of features from said plurality of images; and

analyze said plurality of extracted features in a multi-dimensional space.

13. The system of claim 12, wherein said multi-dimensional space provides a probability distribution function of said image data.

14. The system of claim 12, wherein said processor is further configured to cluster said extracted feature data to identify at least one repetitive pattern of behavior.

15. The system of claim 14, wherein said processor is further configured to compute a mean and variance of each cluster.

16. The system of claim 14, wherein a cluster of data corresponds to a pattern of behavior.

17. The system of claim 12, wherein said processor is further configured to fit said extracted feature data to a probability distribution function to identify at least one Gaussian having a mean and a variance.

18. The system of claim 17, wherein a Gaussian corresponds to a pattern of behavior.

19. An article of manufacture for modeling behavior of an animate object, said article of manufacture comprising:

a computer-readable medium having computer-readable code means embodied thereon, said computer-readable program code means comprising;

a step to obtain a plurality of images;

a step to extract a plurality of features from said plurality of images; and

a step to analyze said plurality of extracted features in a multi-dimensional space.

20. The article of manufacture of claim 19, wherein said multi-dimensional space provides a probability distribution function of said image data.