Shape Retrieval Using Shape Contexts and Cyclic Dynamic Time Warping
Belongie et al. used sets of shape contexts for contours at certain landmarks and showed that they offer good results in shape matching. We propose a better selection of landmark points based on a low-pass filtering of the shape contour and consider that shape context at landmarks along the contour form a cyclic sequence. These cyclic sequences can be properly compared by means of Cyclic Dynamic Time Warping, as shown in the paper. Experiments on the MPEG7 CE-Shape-1 and the SQUID Demo databases show that our proposal outperforms the WARP system and Belongie’s approach for shape retrieval.
KeywordsDynamic Time Warping Uniform Spacing Optimal Alignment Shape Match Cyclic Shift
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- 5.Folkers, A., Samet, H.: Content-based Image Retrieval Using Fourier Descriptors on a Logo Database. In: Proc. of the 16th Int. Conf. on Pattern Recognition, pp. 521–524 (2002)Google Scholar
- 7.Latecki, J., Lakämper, R., Eckhardt, U.: Shape descriptors for non-rigid shapes with a single closed contour. In: Proc. of the IEEE Conf. on Computer Vision and Pattern Recognition, pp. 424–429 (2000)Google Scholar
- 10.Mokhtarian, F., Kittler, J., Abbasi, S.: Shape queries using image databases, http://www.ee.surrey.ac.uk/Research/VSSP/imagedb/demo.html
- 11.Mokhtarian, F., Abbasi, S., Kittler, J.: Robust and efficient shape indexing through curvature scale space. In: BMVC (1996)Google Scholar
- 13.Sankoff, D., Kruskal, J. (eds.): Time warps, string edits, and macromolecules: the theory and practice of sequence comparison. Addison-Wesley, Reading (1983)Google Scholar