1. Tracking objects using Gabor filters
Mark de Greef, Sjoerd Kerkstra, Roeland Weve
Supervisor: Theo Gevers

2. Tracking objects using Gabor filters
Overview
Introduction
Color spaces
Feature selection and mean shift
Demonstration
Conclusion
Tracking objects using Gabor filters

3. Tracking objects using Gabor filters
Introduction
Goal: investigate the use of texture in tracking.
Trackers often use color features (like RGB)
Color features are not sufficient for tracking in some cases
We use texture information as a basis for tracking
Our tracker is based on the on-line feature selection framework.
Tracking objects using Gabor filters

4. Tracking objects using Gabor filters
Color spaces
RGB
rgb
HSV
Intensity
Tracking objects using Gabor filters

5. Tracking objects using Gabor filters
Captures localized frequency information
Biologically motivated
Tracking objects using Gabor filters

6. Tracking objects using Gabor filters
1D Gabor * =
Tracking objects using Gabor filters

7. Tracking objects using Gabor filters
2D Log-Gabor * =
Tracking objects using Gabor filters

8. Inverse Fourier transform
IFFT ->
Tracking objects using Gabor filters

9. Tracking objects using Gabor filters
Feature selection
1D histograms
Background/object separation
Tracking objects using Gabor filters

10. Tracking objects using Gabor filters
Mean shift tracking
Probability density of target model and target candidate
Try to minimize distance between probability densities
Tracking objects using Gabor filters

11. Tracking objects using Gabor filters
Demonstration
Tracking objects using Gabor filters

12. Tracking without log-Gabor

13. Tracking without log-Gabor

14. Tracking a grid ball

15. Tracking using log-Gabor
Tracking objects using Gabor filters

16. Tracking objects using Gabor filters
Tracking a leaf
Tracking objects using Gabor filters

17. Tracking objects using Gabor filters
Tracking without log-Gabor
Tracking objects using Gabor filters

18. Tracking a leaf

19. Tracking objects using Gabor filters
Tracking with log-Gabor
Tracking objects using Gabor filters

20. Tracking objects using Gabor filters
Tracking a soccer ball
Tracking objects using Gabor filters

21. Tracking without log-Gabor
Tracking objects using Gabor filters

22. Tracking objects using Gabor filters
Tracking a soccer ball
Tracking objects using Gabor filters

23. Tracking with log-Gabor
Tracking objects using Gabor filters

24. Tracking objects using Gabor filters
Problems
High wavelength log-Gabor filters
A frame in the soccer game movie
Tracking objects using Gabor filters

25. Problems High wavelength filters pollute feature selection
Solved by limiting wavelength of log-Gabor filter to 2*min(h,w)

26. Tracking objects using Gabor filters
Conclusion
Log-Gabor filters make tracking possible in situations where color features do not
Problems with large wavelengths can be avoided
Addition of log-Gabor features to color features does not degrade tracking performance
Tracking objects using Gabor filters

27. Tracking objects using Gabor filters
Questions?
Tracking objects using Gabor filters