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In this paper, a composite descriptor for shape retrieval has been proposed. The proposed descriptor is obtained from generic fourier descriptors (GFD) for the shape region and the shape contour. A composite descriptor derived from GFD of the shape region and the shape contour is used for indexing and retrieval of shapes. Difference between two images is computed as the Euclidean distance between their composite descriptors. Experiments are performed to test the effectiveness of the proposed descriptor for retrieval of 2d images. Sets of composite descriptors, obtained by assigning different weights to the region component and the contour component, are also evaluated. Item S8 within the MPEG-7 still images content set is used for performing experiments; this dataset consists of 3621 still images. Experimental results show that the proposed descriptor is effective.

In this paper, spherical harmonics are proposed as shape descriptors for 2D images. We introduce the concept of connectivity; 2D images are decomposed using connectivity, which is followed by 3D model construction. Spherical harmonics are obtained for 3D models and used as descriptors for the underlying 2D shapes. Difference between two images is computed as the Euclidean distance between their spherical harmonics descriptors. Experiments are performed to test the effectiveness of spherical harmonics for retrieval of 2D images. Item S8 within the MPEG-7 still images content set is used for performing experiments; this dataset consists of 3621 still images. Experimental results show that the proposed descriptors for 2D images are effective

Obtaining high quality content in an e-learning portal is critical to maximise the learning experience. For e-learning portals the content specialists are the publishers. Typically, publishers are nominated by portal administrators to make their content available to instructors. Instructors subsequently customise the portal by selecting content according to their requirements. The choice of content is limited to that provided by the publishers. This is a rigid system owing to the fact that instructors do not have access to an exhaustive range of content. We propose a system based on XML Web services which can be adopted by publishers in adherence with a number of emerging Web standards including SOAP and UDDI to disseminate their content. This system can be leveraged by portals to preview and subsequently acquire content which best suits the requirements as determined by instructors.

Previously, we proposed the concept of connectivity to obtain discriminating shape descriptors. In this paper, we use connectivity to obtain superior distance histograms for multi-scale images. Experiments are performed to evaluate the distance histograms, based on connectivity, for shape-based retrieval of multi-scale images. Item S8 within the MPEG-7 still images content set is used for performing experiments. Experimental results show that the proposed method enhances retrieval performance significantly.

UDDI is a standard for publishing and discovery of web services. UDDI registries provide keyword searches for web services. The search functionality is very simple and fails to account for relationships between web services. In this paper, we propose an algorithm which retrieves closely related web services. The proposed algorithm is based on singular value decomposition (SVD) in linear algebra, which reveals semantic relationships among web services. The preliminary evaluation shows the effectiveness and feasibility of the algorithm.

Segmented object shape is an important visual feature and one of the content based image retrieval techniques is the shape based technique which allows users to ask or objects similar in shape to a query object. We describe a method for shape representation and similarity measure which we call the grid based method and evaluate its performance by comparing it with two popular methods, namely, the Fourier descriptors method and the moment invariants method. The comparative study is done by performing the same queries on the same database for all the methods. We also test the methods for robustness to noise by performing the queries on the database of noisy shapes. Experimental results show that the method proposed by us performs favorably compared with the other two methods.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.