1. Department of Computer Science Center for Visual Computing Bag-of-Feature-Graphs: A New Paradigm for Non-rigid Shape Retrieval Tingbo HOU, Xiaohua HOU, Ming ZHONG and Hong QIN Department of Computer Science Stony Brook University (SUNY SB) ICPR 2012

2. Department of Computer Science Center for Visual Computing Nonrigid Shape Retrieval ICPR 2012 … … Shape Query Shape Database Retrieved Shapes

3. Department of Computer Science Center for Visual Computing Overview of BoFG  Inspired by the ideas from Bag-of-Words (BoW) and Spatial- Sensitive Bag-of-Words (SS-BoW)  Feature-driven  Concise and fast to compute  Spatially informative ICPR 2012

4. Department of Computer Science Center for Visual Computing Previous Works Relevant to This Project  Bag-of-Words 1.Y. Liu, H. Zha, and H. Qin. CVPR, 2006. 2.H. Tabia, M. Daoudi, J. P. Vandeborre, and O. Colot. 3DOR, 2010. 3.R. Toldo, U. Castellani, and A. Fusiello. VC, 2010. 4.G. Lavoué. 3DOR, 2011.  Shape Google (Spatially-Sensitive Bag-of-Words) 1.M. Ovsjanikov, A. M. Bronstein, L. J. Guibas and M. M. Bronstein. NORDIA, 2009. 2.(SI-HKS) M. M. Bronstein and I. Kokkinos. CVPR, 2010. 3.A. M. Bronstein, M. M. Bronstein, L. J. Guibas, and M. Ovsjanikov. ACM TOG, 2011. ICPR 2012

5. Department of Computer Science Center for Visual Computing Background (1) ICPR 2012

6. Department of Computer Science Center for Visual Computing Background (2) ICPR 2012

7. Department of Computer Science Center for Visual Computing Shape-Google Revisit (1) ICPR 2012

8. Department of Computer Science Center for Visual Computing Shape-Google Revisit (2) ICPR 2012

9. Department of Computer Science Center for Visual Computing New Paradigm: Bag-of-Feature Graphs (1)  Motivation: Reduce computation complexity  Considering all points on shape -> only considering feature points  Vector/matrix of word frequencies -> feature graphs associated with words ICPR 2012

10. Department of Computer Science Center for Visual Computing Formulation (1) ICPR 2012 …

11. Department of Computer Science Center for Visual Computing Formulation (2) ICPR 2012

12. Department of Computer Science Center for Visual Computing Nonrigid Shapes and Their BoFG Descriptors ICPR 2012

13. Department of Computer Science Center for Visual Computing Time Complexity of BoW, SS-BOW and BoFG ICPR 2012

14. Department of Computer Science Center for Visual Computing Experiments ICPR 2012 1 http://toca.cs.technion.ac.il/book/shrec.html

15. Department of Computer Science Center for Visual Computing ICPR 2012

16. Department of Computer Science Center for Visual Computing Experiments ICPR 2012 Time performance (in seconds) of three descriptors on two shapes with 3K and 30k vertices

17. Department of Computer Science Center for Visual Computing Experiments Precision-recall curves of evaluated methods, with categories of (1) null, (2) scale changes and (3) holes. ICPR 2012 (1)(2) (3)

18. Department of Computer Science Center for Visual Computing Partial shape retrieval  Query shape is only a part of a complete model  Online feature alignment is required to extract corresponding sub- graphs ICPR 2012

19. Department of Computer Science Center for Visual Computing Summary  Bag-of-Feature-Graphs (BoFG) is a new paradigm for shape representation  This representation is feature-driven, concise, and spatially-aware  The key idea is to construct graphs of features associated with geometric words  BoFG has much improved time-performance and competitive retrieval results in comparison with other state-of-the-art methods ICPR 2012

20. Department of Computer Science Center for Visual Computing Future Work  Investigate graph comparison with heavy outliers  Improve the performance on partial shape retrieval  Acknowledgements: Research Grants from National Science Foundation ICPR 2012

21. Department of Computer Science Center for Visual Computing ICPR 2012