A Real-Time Approach of Level-Set-Based Contour Tracking for Accurate Foreground Extraction

Real-time contour tracking in video surveillance suffers the problem of low speed and influence of shadows and noises. In this paper, a novel approach of video tracking is proposed, which employs a faster level-set-based method and a foreground extracting method free of noises. Compared with traditional level-set-based methods, our method avoids the high computational complexity of solving partial differential equations. In addition to the fast tracking method, we analyze the color information in the RGB color space so that the shadows and noises are eliminated in foreground extraction. It is performed without any manual thresholds’ tuning. Furthermore, we make use of the foreground extraction process to get the coarse contour of the object, which is also performed automatically and significantly reduces the time spent in the curve evolution step. With this approach, real-time surveillance system can be implemented. Experiments show that our approach outperforms previous methods for indoor environments.

[1]  Alper Yilmaz,et al.  Level Set Methods , 2007, Wiley Encyclopedia of Computer Science and Engineering.

[2]  Touradj Ebrahimi,et al.  Detecting shadows in image sequences , 2004 .

[3]  J. Sethian,et al.  Fronts propagating with curvature-dependent speed: algorithms based on Hamilton-Jacobi formulations , 1988 .

[4]  Michel Barlaud,et al.  Detection and Tracking of Moving Objects using a New Level Set Based Method , 2000, ICPR.

[5]  Na Li,et al.  Real-time video object segmentation using HSV space , 2002, Proceedings. International Conference on Image Processing.

[6]  Demetri Terzopoulos,et al.  Snakes: Active contour models , 2004, International Journal of Computer Vision.

[7]  J A Sethian,et al.  A fast marching level set method for monotonically advancing fronts. , 1996, Proceedings of the National Academy of Sciences of the United States of America.

[8]  S. Osher,et al.  Level set methods: an overview and some recent results , 2001 .

[9]  W. Clem Karl,et al.  Real-time tracking using level sets , 2005, 2005 IEEE Computer Society Conference on Computer Vision and Pattern Recognition (CVPR'05).

[10]  J. Sethian,et al.  FRONTS PROPAGATING WITH CURVATURE DEPENDENT SPEED: ALGORITHMS BASED ON HAMILTON-JACOB1 FORMULATIONS , 2003 .

[11]  Jun-Wei Hsieh,et al.  Tracking Multiple Moving Objects Using A Level-Set Method , 2004, Int. J. Pattern Recognit. Artif. Intell..