17484895
Sequential processing for content-based retrieval of composite objects
It is becoming increasingly important for multimedia databases to provide capabilities for content-based retrieval of composite objects. Composite objects consist of several simple objects which have feature, spatial, temporal, semantic attributes, and spatial and temporal relationships between them. A content-based composite object query is satisfied by evaluating a program of content-based rules (i.e., color, texture), spatial and temporal rules (i.e., east, west), fuzzy conjunctions (i.e., appears similar AND is spatially near) and database lookups (i.e., semantics). We propose a new sequential processing method for efficiently computing content-based queries of composite objects. The proposed method evaluates the composite object queries by (1) defining an efficient ordering of the sub-goals of the query, which involve spatial, temporal, content-based and fuzzy rules, (2) developing a query block management strategy for generating, evaluating, and caching intermediate sub-goal results, and (3) conducting a best-first dynamic programming-based search with intelligent back-tracking. The method is guaranteed to find the optimal answer to the query and reduces the query time by avoiding the exploration of unlikely candidates.
30741426
Multimedia database management systems
Introduction. Multimedia Data Types and Formats. Multimedia Database Design Issues. Text Document Indexing and Retrieval. Indexing and Retrieval of Audio. Image Indexing and Retrieval. Video Indexing and Retrieval. Integrated Multimedia Indexing and Retrieval. Techniques and Data Structures for Efficient Multimedia Similarity Search. System Support for Distributed Multimedia Databases. Measurement of Multimedia Information Retrieval Effectiveness. Products, Applications, and New Developments.
2339969
Interactive search fusion methods for video database retrieval
In this paper, we investigate a new method for video database retrieval using interactive search fusion. Recent video analysis techniques have enabled the extraction of a variety of descriptors of features, concepts, clusters, classification results, speech and textual terms, MPEG-7 metadata, and so on. However, given an information need users are faced with a daunting task of trying to formulate queries over these multiple disparate data sources in order to retrieve the desired video content. In this paper, we explore a novel approach based on search fusion in which the user interactively builds a query by sequentially choosing among the descriptors and data sources and by selecting from various combining and score aggregation functions to fuse results of individual searches. For example, the system allows building of queries such as "retrieve video clips that have color of beach scenes, the detection of sky, and detection of water". In this paper we present the search fusion method and evaluate the performance on a large video database.
20964781
Special Issue on Image Understanding for Digital Photographs
15943562
Content-based transcoding of images in the Internet
We present a system for transcoding images in the Internet in order to improve their delivery to client devices with a wide range of communication, processing, storage and display capabilities. The content-based image transcoder analyzes the images in order to classify them into image type and image purpose classes. The system then utilizes transcoding policies based on the content classes to manipulate and transcode the images. We describe the image transcoding process for a variety of client devices, including PDAs, hand-held computers (HHCs), TV browsers and color PCs, and demonstrate improvements in delivery speed and accessibility of the images in the Internet.
1805433
MPEG-7 MDS Content Description Tools and Applications
In this paper, we present the tools specified by the MDS part of the MPEG-7 standard for describing multimedia data such as images and video. In particular, we focus on the description tools that represent the structure and semantics of multimedia data to whose development we have actively contributed. We also describe some of our research prototype systems dealing with the extraction and application of MPEG-7 structural and semantic descriptions. These systems are AMOS, a video object segmentation and retrieval system, and IMKA, an intelligent multimedia knowledge application using the MediaNet knowledge representation framework.
17816721
Triangle Guarding
We consider the problem of triangle guarding ( -guarding) a simple, 2D polygon Q. A polygon Q is -guarded if every point q of Q is contained in the convex hull of some three guards that can all see q. This rather odd condition approximates a desire, for example, to see all sides of q or to locate (via triangulation) q from at least two angularly well-separated views. If we restrict the guards to lie in Q and Q has a transparent boundary then the vertices of the convex hull of Q (CH (Q)) form the minimum set of -guards. We examine two other variations of the problem. In the first, the guards may be placed within a transparent border surrounding Q. For this variation, we describe a polynomial time algorithm, related to the classic algorithm for finding min-link separators, that finds a minimum set of -guards. In the second, we consider the case where Q’s boundary is opaque and show that, as in the traditional art gallery problem, finding a minimum set of vertex -guards is NP-hard. Transparent Fences Given simple polygons P and Q with Q contained in P , where |Q|+ |P | = n, what is the minimum number and placement of guards in P needed to -guard Q, assuming that both Q and P have transparent boundaries? Our algorithm for this problem is inspired by an algorithm for finding min-link separators between two convex polygons, one contained in the other [1]. The following basic lemmas motivate using this approach. Define legal regions to be regions of the outer polygon P , that are not contained in the interior of CH (Q) (Figure 1).
13121681
A parallel algebra for object databases
The paper describes an algebra for use with parallel object databases, and in particular ODMG compliant databases with OQL. Although there have been many proposals for parallel relational database systems, there has been much less work on parallel object databases, and on parallel query processing for object databases. The parallel algebra presented in the paper is an extension of an existing physical algebra for OQL, and has an important role during query optimization, and for describing execution plans. The paper presents not only the algebra, but also its role in the architecture of a parallel database.
18781640
An Analysis of the Alias Method for Discrete Random-Variate Generation
This paper introduces and studies an optimization problem related to the alias method for discrete random-variate generation. The alias method is an efficient method to generate random variates from a discrete probability distribution. The efficiency of the alias method can be improved by designing the alias table such that the expected number of computations that must be performed per value generated is minimized. The problem of optimizing the construction of the alias table is proven to be strongly NP-hard, even if either of two variations of the alias method relaxing the alias-table-generation restrictions are used. Integer-programming formulations describing these three optimization problems are presented, and insights regarding necessary optimality criteria and relationships among their optimal solutions are discussed.
16384039
Experimenting with object navigation in parallel object databases
This paper addresses the problem of selecting the best object navigation strategy for a query to be run in parallel, when considering multiple alternative strategies. This is done by performing experiments with three pointer-based join algorithms, running simple and complex queries in a parallel ODMG-compliant object database system. We believe our results provide insights into how physical properties of queries impact on the performance of different joins operators in a parallel environment.
37305588
A dynamic programming algorithm for the conditional covering problem on tree graphs
In a previous article, we presented algorithms for solving the Conditional Covering Problem (CCP) on path and extended star graphs. The CCP on these graphs can be solved in O(n2) time, where n is the number of nodes in the graph. In this article, we propose a new dynamic programming procedure to solve the CCP on tree graphs. This recursion works from the leaf nodes of the tree up to the root node, using notions of protected and unprotected costs as done for the CCP path algorithm in our previous work. We introduce new preliminary routines and data structures to merge information from subpaths and subtrees, resulting in an O(n4) algorithm to optimally solve the problem. © 2005 Wiley Periodicals, Inc. NETWORKS, Vol. 46(4), 186–197 2005