Computer vision-based object tracking system

• US 20070273766A1
• Filed: 05/23/2006
• Published: 11/29/2007
• Est. Priority Date: 05/23/2006
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Wilson, Andrew D.
• Granted Patent: US 8,803,978 B2
• Time in Patent Office: Days
• US Class Current: 348/169
• CPC Class Codes: G01S 3/7864 T.V. type tracking systems
• CPC Class Codes: G06T 2207/30241 Trajectory
• CPC Class Codes: G06T 7/246 using feature-based methods, e.g. the tracking of corners or segments
• CPC Class Codes: G06V 10/62 relating to a temporal dimension, e.g. time-based feature extraction; Pattern tracking
• CPC Class Codes: H04N 25/443 by reading pixels from selected 2D regions of the array, e.g. for windowing or digital zooming
• CPC Class Codes: H04N 25/76 Addressed sensors, e.g. MOS or CMOS sensors
• CPC Class Codes: H04N 3/155 Control of the image-sensor operation, e.g. image processing within the image-sensor
• CPC Class Codes: H04N 5/33 Transforming infrared radiation cameras or camera modules for generating image signals from infrared radiation H04N23/20; circuitry of SSIS for transforming infrared radiation into image signals H04N25/20

Abstract

A computer-implemented method for utilizing a camera device to track an object is presented. As part of the method, a region of interest is determined within an overall image sensing area. A point light source is then tracked within the region of interest. In a particular arrangement, the camera device incorporates CMOS image sensor technology and the point light source is an IR LED. Other embodiments pertain to manipulations of the region of interest to accommodate changes to the status of the point light source.

Claims

1. A computer-implemented method of utilizing a camera device to track an object, the method comprising:

determining a region of interest within an overall image sensing area; and

tracking a point light source within the region of interest, the point light source being associated with the object.

2. The method of claim 1, wherein tracking comprises tracking with a CMOS image sensor.

3. The method of claim 2, wherein tracking a light source comprises tracking an IR LED.

4. The method of claim 2 further comprising re-determining the region of interest when the point light source moves to a location that is beyond a predetermined threshold.

5. The method of claim 1, wherein tracking a point light source comprises tracking an LED.

6. The method of claim 1, wherein tracking a point light source comprises tracking an IR LED.

7. The method of claim 1, wherein determining a region of interest comprises increasing the size of the region of interest when the point light source is not detected.

8. The method of claim 1, wherein determining a region of interest comprises decreasing the size of the region of interest upon detection of the point light source.

9. The method of claim 1 further comprising re-determining the region of interest upon movement of the point light source.

10. The method of claim 1 further comprising actively adjusting the region of interest to accommodate movement of the point light source.

11. The method of claim 1 wherein determining the region of interest comprises limiting the region of interest based on a calculated potential for movement of the point light source.

12. A computer vision-based object tracking system, the system comprising:

an object;

a point light source that is associated with the object such that the point light source moves when the object moves; and

a camera device configured to track the object by tracking the point light source, the camera device being further configured to track the point light source within a region of interest that is less than an overall image sensing area.

13. The system of claim 12, wherein the camera device is configured to track the point light source using a CMOS image sensor.

14. The system of claim 12, wherein the point light source is an IR LED.

15. The system of claim 12, wherein the camera device is configured to track the point light source within a different region of interest when the point light source moves to a location that is beyond a predetermined threshold.

16. A computer-implemented method of utilizing a camera device to track an object, the method comprising adjusting a characteristic of a region of interest based on a characteristic of a point light source associated with the object, wherein the region of interest is a region within an overall image sensing area.

17. The method of claim 16, wherein adjusting a characteristic of the region of interest comprises increasing the size of the region of interest when the point light source is not detected.

18. The method of claim 16, wherein adjusting a characteristic of the region of interest comprises relocating the region of interest when the point light source moves.

19. The method of claim 16, wherein adjusting a characteristic of a region of interest comprises relocating the region of interest when the point light source moves beyond a predetermined threshold.

20. The method of claim 16, wherein the point light source is an IR LED.