Browsing by Author "Lin, BS"

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2D C-tree spatial representation for iconic image
(1999-04-01)
Hsu, FJ
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Lee, SY
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Lin, BS
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資訊科學與工程研究所
;
Institute of Computer Science and Engineering
The 2D string approaches provide a natural way of constructing iconic indexing for images. The 2D C-string representation with an efficient cutting mechanism is more characteristic of spatial knowledge and efficient in the representation of iconic images. However, the computation of object ranks in a 2D C-string might make the inference of spatial reasoning somewhat complicated. This shortcoming is overcome by the 2D C-tree representation. The 2D C-tree not only keeps the comprehensive spatial knowledge in the original 2D C-string, but also the ordered labeled tree is more suitable for spatial reasoning and image retrieval. The spatial knowledge can be derived directly from the inference rules embedded in the characteristic structure of the 2D C-tree representation. (C) 1999 Academic Press.
Similarity retrieval by 2D C-trees matching in image databases
(1998-03-01)
Hsu, FJ
;
Lee, SY
;
Lin, BS
;
資訊科學與工程研究所
;
Institute of Computer Science and Engineering
The image retrieval based on spatial content is an attracting task in many image database applications. The 2D strings provide a natural way of constructing spatial indexing for images and support effective picture query. Nevertheless, the 2D string is deficient in describing the spatial knowledge of nonzero sized objects with overlapping. In this paper, we use an ordered labeled tree, a 2D C-tree, to be the spatial representation for images and propose the tree-matching algorithm for similarity retrieval. The distance between 2D C-trees is used to measure the similarity of images. The proposed tree comparison algorithm is also modified to compute the partial tree distance for subpicture query. Experimental results for verifying the effectiveness of similarity retrieval by 2D C-trees matching are presented. (C) 1998 Academic Press.
Video data indexing by 2D C-trees
(1998-08-01)
Hsu, FJ
;
Lee, SY
;
Lin, BS
;
資訊工程學系
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Department of Computer Science
Video data contains a large amount of spatial and temporal information. The changes of video frames are quite useful for motion analysis and cannot be provided by other media easily. Chang et al: had proposed an effective 2D string approach for spatial indexing of image data. In this paper, we extend this iconic approach and apply it to video data indexing. We propose 2D C-trees to represent the spatial content within individual frames. A video sequence can then be represented and indexed by a temporal set or an ordering set of 2D C-trees. The similarity retrieval of video matching problem becomes the problem of video sequence matching by computing the similarity, or the minimum cost of matched frames. We present three schemes, full-sequence matching, segment matching and subsequence matching, for video information retrieval. The matching schemes can be modified and extended to approximate sequence matching by computing the partial distance for providing a comprehensive retrieval of video data. A prototype video information system is also developed to validate the effectiveness of video data indexing by 2D C-trees. (C) 1998 Academic Press.