Object initialization in video tracking

Abstract

A system and method initializes objects in video data. In an embodiment, the video data is an output of a video tracker, and in a particular embodiment, the video tracker is a particle filter. A histogram is calculated that indicates a number of particles that do not cover an object in an input image from the particle filter at a position in the input image. The system and method then initializes an object to be tracked in the input image as a function of the histogram.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example embodiment of a process to initialize an object in a video tracker.

FIG. 2 illustrates an example embodiment of a human template.

FIG. 3 illustrates an example embodiment of a vehicle template.

FIG. 4A illustrates a binary image.

FIG. 4B illustrates an example of an Uncovered Object Histogram.

FIG. 5A illustrates an input binary image.

FIG. 5B illustrates several possible templates covering a portion of an object in the input image of FIG. 5A.

FIG. 5C illustrates a result of a template optimization procedure applied to FIG. 5B.

FIG. 6 illustrates an example embodiment of a computer architecture upon which one or more embodiments of an object initialization process may operate.

Claims

1. A method comprising: configuring a video system to: track objects using a particle filter;calculate a histogram indicating a number of particles that do not cover an input image at a position in said input image; andinitialize an object to be tracked in said input image as a function of said histogram.

2. The method of claim 1, wherein said initialization comprises an optimization algorithm using criteria based on said histogram.

3. The method of claim 1, wherein said histogram comprises an Uncovered Object Histogram (UOH), and further wherein said UOH is calculated by comparing each of said number of particles to said input image.

4. The method of claim 3, wherein said comparison comprises:

5. The method of claim 4, wherein said initialization further comprises positioning templates in a three-dimensional space based on said calculated UOH.

6. The method of claim 5, wherein said templates minimize said calculated UOH when said templates are added to all particles in said particle set.

7. The method of claim 6, wherein said minimization comprises positioning said templates as follows:

8. A system comprising: a module to track objects using a particle filter;a module to calculate a histogram indicating a number of particles that do not cover an input image at a position in said input image; anda module to initialize an object to be tracked in said input image as a function of said histogram.

9. The system of claim 8, wherein said module to initialize comprises an optimization algorithm using criteria based on said histogram.

10. The system of claim 8, wherein said histogram comprises an Uncovered Object Histogram (UOH), and further comprising a module to calculate said UOH by comparing each of said number of particles to said input image.

11. The system of claim 10, wherein said calculation module comprises:

12. The system of claim 11, wherein said initialization module further comprises positioning templates in a three-dimensional space based on said calculated UOH.

13. The system of claim 12, wherein said templates minimize said calculated UOH when said templates are added to all particles in said particle set.

14. The system of claim 13, wherein said minimization comprises positioning said templates as follows:

15. A machine readable medium comprising instructions for executing a method comprising: configuring a video system to: track objects using a particle filter;calculate a histogram indicating a number of particles that do not cover an input image at a position in said input image; andinitialize an object to be tracked in said input image as a function of said histogram.

16. The machine readable medium of claim 15, wherein said initialization comprises an optimization algorithm using criteria based on said histogram.

17. The machine readable medium of claim 15, wherein said histogram comprises an Uncovered Object Histogram (UOH), and further wherein said UOH is calculated by comparing each of said number of particles to said input image.

18. The machine readable medium of claim 17, wherein said comparison comprises:

19. The machine readable medium of claim 18, wherein said initialization further comprises positioning templates in a three-dimensional space based on said calculated UOH.

20. The machine readable medium of claim 19, wherein said templates minimize said calculated UOH when said templates are added to all particles in said particle set; and further whereinsaid minimization comprises positioning said templates as follows: