SYSTEM AND METHOD FOR WAVING DETECTION BASED ON OBJECT TRAJECTORY

• US 20100027846A1
• Filed: 07/31/2008
• Published: 02/04/2010
• Est. Priority Date: 07/31/2008
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd. (Samsung Group)
• Original Assignee: Samsung Electronics Co. Ltd. (Samsung Group)
• Inventors: Xu, Ning, Guan, Haiying
• Granted Patent: US 8,433,101 B2
• Time in Patent Office: Days
• US Class Current: 382/107
• CPC Class Codes: G06F 18/29 Graphical models, e.g. Bayesian networks
• CPC Class Codes: G06V 10/84 using probabilistic graphical models from image or video features, e.g. Markov models or Bayesian networks
• CPC Class Codes: G06V 40/20 Movements or behaviour, e.g. gesture recognition recognition of facial expressions G06V40/16

Abstract

A system and method for detecting a waving motion from a sequence of ordered points is disclosed. In one embodiment, the method comprising receiving a sequence of ordered points, selecting a subset of the sequence of ordered points, determining if the subset defines a circular shape, and storing an indication of whether or not the subset defines a waving motion. Various metrics for determining if the subset defines a waving motion, which allow for a trade-off between accuracy and complexity, are disclosed.

Claims

1. A computer-implemented method of detecting a waving motion in a sequence of ordered points, the method comprising:

receiving a sequence of ordered points;

selecting a subset of the sequence of ordered points;

determining if the subset defines a waving motion; and

storing an indication of whether or not the subset defines a waving motion.

2. The method of claim 1, further comprising preprocessing the sequence of ordered points prior to selecting a subset.

3. The method of claim 2, wherein the preprocessing comprises applying at least one of a median filter or an averaging filter.

4. The method of claim 1, wherein the sequence of ordered points is derived from a video sequence.

5. The method of claim 1, wherein determining if the subset defines a waving motion comprises determining a set of extreme points.

6. The method of claim 5, wherein determining if the subset defines a waving motion further comprises determining the number of extreme points, wherein it is determined that the subset defines a waving motion if the number of extreme points is greater than a threshold.

7. The method of claim 5, wherein determining if the subset defines a waving motion further comprises determining the number of points between pairs of successive extreme points, wherein it is determined that the subset defines a waving motion if each of the number of points is between a first threshold and a second threshold.

8. The method of claim 5, wherein determining if the subset defines a waving motion further comprises determining a line segment between each pair of successive extreme points.

9. The method of claim 8, wherein determining if the subset defines a waving motion further comprises determining the angle of each line segment, wherein it is determined that the subset defines a waving motion if the angle of each line segment is between a first threshold and a second threshold.

10. The method of claim 9, wherein the first threshold and second threshold are predetermined.

11. The method of claim 9, wherein the first threshold and second threshold are based on the determined angles.

12. The method of claim 8, wherein determining if the subset defines a waving motion further comprises determining a time span of each line segment, wherein it is determined that the subset defines a waving motion if the time span of each line segment is between a first threshold and a second threshold.

13. The method of claim 8, wherein determining if the subset defines a waving motion further comprises determining a length of each line segment, wherein it is determined that the subset defines a waving motion if the length of each line segment is between a first threshold and a second threshold.

14. The method of claim 8, wherein determining if the subset defines a waving motion further comprises determining a center point of the subset and a center point of each line segment, wherein it is determined that the subset defines a waving motion if a distance between the center point of the subset and the center point of each line segment is between a first threshold and a second threshold.

15. The method of claim 1, further comprising determining if the subset is in a horizontal or vertical orientation, wherein the stored indication is also indicative of the orientation.

16. A system for detecting a waving motion in a sequence of ordered points, the system comprising:

an input configured to receive a sequence of ordered points;

a selection module configured to select a subset of the sequence of ordered points;

a determination module configured to determine if the subset defines a waving motion; and

a memory configured to store an indication of whether or not the subset defines a waving motion.

17. The system of claim 16, wherein the input comprises a camera.

18. The system of claim 16, wherein the system comprises a television, a DVD player, a radio, a set-top box, a music player, or a video player.

19. A system for detecting a waving motion in a sequence of ordered points, the system comprising:

means for receiving a sequence of ordered points;

means for selecting a subset of the sequence of ordered points;

means for determining if the subset defines a waving motion; and

means for storing an indication of whether or not the subset defines a waving motion.

20. A programmable storage device comprising code which, when executed, causes a processor to perform a method of detecting a waving motion in a sequence of ordered points, the method comprising:

receiving a sequence of ordered points;

selecting a subset of the sequence of ordered points;

determining if the subset defines a circular shape; and

storing an indication of whether or not the subset defines a waving motion.