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1.
Abstract. Providing a customized result set based upon a user preference is the ultimate objective of many content-based image retrieval
systems. There are two main challenges in meeting this objective: First, there is a gap between the physical characteristics
of digital images and the semantic meaning of the images. Secondly, different people may have different perceptions on the
same set of images. To address both these challenges, we propose a model, named Yoda, that conceptualizes content-based querying
as the task of soft classifying images into classes. These classes can overlap, and their members are different for different
users. The “soft” classification is hence performed for each and every image feature, including both physical and semantic
features. Subsequently, each image will be ranked based on the weighted aggregation of its classification memberships. The
weights are user-dependent, and hence different users would obtain different result sets for the same query. Yoda employs
a fuzzy-logic based aggregation function for ranking images. We show that, in addition to some performance benefits, fuzzy
aggregation is less sensitive to noise and can support disjunctive queries as compared to weighted-average aggregation used
by other content-based image retrieval systems. Finally, since Yoda heavily relies on user-dependent weights (i.e., user profiles)
for the aggregation task, we utilize the users' relevance feedback to improve the profiles using genetic algorithms (GA).
Our learning mechanism requires fewer user interactions, and results in a faster convergence to the user's preferences as
compared to other learning techniques.
Correspondence to: Y.-S. Chen (E-mail: yishinc@usc.edu)
This research has been funded in part by NSF grants EEC-9529152 (IMSC ERC) and IIS-0082826, NIH-NLM R01-LM07061, DARPA and
USAF under agreement nr. F30602-99-1-0524, and unrestricted cash gifts from NCR, Microsoft, and Okawa Foundation. 相似文献
2.
A multimedia application involves information that may be in a form of video, images, audio, text and graphics, need to be
stored, retrieved and manipulated in large databases. In this paper, we propose an object-oriented database schema that supports
multimedia documents and their temporal, spatial and logical structures. We present a document example and show how the schema
can adress all the structures described. We also present a multimedia query specification language that can be used to describe
a multimedia content portion to be retrieved from the database. The language provides means by which the user can specify
the information on the media as well as the temoral and spatial relationships among these media. 相似文献
3.
Paola Carrara Daniela Fogli Giuseppe Fresta Piero Mussio 《Universal Access in the Information Society》2002,1(4):288-304
This paper proposes a new effective strategy for designing and implementing interactive systems overcoming culture, skill
and situation hurdles in Human-Computer Interaction (HCI). The strategy to identify and reduce these hurdles is developed
in the framework of a methodology based on a recently introduced model of HCI, and exploits the technological innovations
of XML (Extensible Markup Language). HCI is modelled as a cyclic process in which the user and the interactive system communicate
by materializing and interpreting a sequence of messages. The interaction process is formalized by specifying both the physical
message appearance and the computational aspect of the interaction. This formalization allows the adoption of notation traditionally
adopted by users in their workplaces as the starting point of the interactive system design. In this way, the human–system
interaction language takes into account the users’ culture. Moreover, the methodology permits user representatives to build
a hierarchy of systems progressively adapted to users’ situations, skills and habits, according to the work organization in
the domain considered. The strategy is proved to be effective by describing how to implement it using BANCO (Browsing Adaptive
Network for Changing user Operativity), a feasibility prototype based on XML, which allows the hierarchy implementation and
system adaptations. Several examples from an environmental case under study are used throughout the paper to illustrate the
methodology and the effectiveness of the technology adopted.
Published online: 4 June 2002 相似文献
4.
Integrated spatial and feature image query 总被引:3,自引:0,他引:3
We present a new system for querying for images by regions and their spatial and feature attributes. The system enables the
user to find the images that contain arrangements of regions similar to those diagrammed in a query image. By indexing the
attributes of regions, such as sizes, locations and visual features, a wide variety of complex joint spatial and feature queries
are efficiently computed. In order to demonstrate the utility of the system, we develop a process for the extracting color
regions from photographic images. We demonstrate that integrated spatial and feature querying using color regions improves
image search capabilities over non-spatial content-based image retrieval methods. 相似文献
5.
Curvature scale space image in shape similarity retrieval 总被引:7,自引:0,他引:7
6.
NeTra: A toolbox for navigating large image databases 总被引:17,自引:0,他引:17
We present here an implementation of NeTra, a prototype image retrieval system that uses color, texture, shape and spatial
location information in segmented image regions to search and retrieve similar regions from the database. A distinguishing
aspect of this system is its incorporation of a robust automated image segmentation algorithm that allows object- or region-based
search. Image segmentation significantly improves the quality of image retrieval when images contain multiple complex objects.
Images are segmented into homogeneous regions at the time of ingest into the database, and image attributes that represent
each of these regions are computed. In addition to image segmentation, other important components of the system include an
efficient color representation, and indexing of color, texture, and shape features for fast search and retrieval. This representation
allows the user to compose interesting queries such as “retrieve all images that contain regions that have the color of object
A, texture of object B, shape of object C, and lie in the upper of the image”, where the individual objects could be regions
belonging to different images. A Java-based web implementation of NeTra is available at http://vivaldi.ece.ucsb.edu/Netra. 相似文献
7.
Lawrence D. Bergman Jerre Shoudt Vittorio Castelli Chung-Sheng Li Loey Knapp 《International Journal on Digital Libraries》1999,2(2-3):178-189
In this paper, we describe a new interface for querying multimedia digital libraries and an interface building framework.
The interface employs a drag-and-drop style of interaction and combines a structured natural-language style query specification
with reusable multimedia objects. We call this interface DanDMM, short for “drag-and-drop multimedia”. DanDMM interfaces capture
the syntax of the underlying query language, and dynamically reconfigure to reflect the contents of the data repository.
A distinguishing feature of DanDMM is its ability to synthesize integrated interfaces that incorporate both example-based
specification using multimedia objects, and traditional techniques including keyword, attribute, and free text-based search.
We describe the DanDMM-builder, a framework for synthesizing DanDMM interfaces, and give several examples of interfaces that
have been constructed using DanDMM-builder, including a remote-sensing library application and a video digital library.
Received: 15 December 1997 / Revised: June 1999 相似文献
8.
Christian Shin David Doermann Azriel Rosenfeld 《International Journal on Document Analysis and Recognition》2001,3(4):232-247
Searching for documents by their type or genre is a natural way to enhance the effectiveness of document retrieval. The layout
of a document contains a significant amount of information that can be used to classify it by type in the absence of domain-specific
models. Our approach to classification is based on “visual similarity” of layout structure and is implemented by building
a supervised classifier, given examples of each class. We use image features such as percentages of text and non-text (graphics,
images, tables, and rulings) content regions, column structures, relative point sizes of fonts, density of content area, and
statistics of features of connected components which can be derived without class knowledge. In order to obtain class labels
for training samples, we conducted a study where subjects ranked document pages with respect to their resemblance to representative
page images. Class labels can also be assigned based on known document types, or can be defined by the user. We implemented
our classification scheme using decision tree classifiers and self-organizing maps.
Received June 15, 2000 / Revised November 15, 2000 相似文献
9.
The development of a system supporting querying of image databases by color content tackles a major design choice about properties
of colors which are referenced within user queries. On the one hand, low-level properties directly reflect numerical features
and concepts tied to the machine representation of color information. On the other hand, high-level properties address concepts
such as the perceptual quality of colors and the sensations that they convey. Color-induced sensations include warmth, accordance or contrast, harmony, excitement, depression, anguish, etc. In other words, they refer to the semantics of color usage. In particular, paintings are an example where the message is contained more in the high-level color qualities
and spatial arrangements than in the physical properties of colors. Starting from this observation, Johannes Itten introduced
a formalism to analyze the use of color in art and the effects that this induces on the user's psyche. In this paper, we present
a system which translates the Itten theory into a formal language that expresses the semantics associated with the combination
of chromatic properties of color images. The system exploits a competitive learning technique to segment images into regions
with homogeneous colors. Fuzzy sets are used to represent low-level region properties such as hue, saturation, luminance,
warmth, size and position. A formal language and a set of model-checking rules are implemented to define semantic clauses
and verify the degree of truth by which they hold over an image. 相似文献
10.
Ezio Berenci Claudio Carpineto Vittorio Giannini Stefano Mizzaro 《International Journal on Digital Libraries》2000,3(3):249-260
We present an approach to increasing the effectiveness of ranked-output retrieval systems that relies on graphical display
and user manipulation of “views” of retrieval results, where a view is the subset of retrieved documents that contain a specified
subset of query terms. This approach has been implemented in a system named VIEWER (VIEwing WEb Results), acting as an interface
to available search engines. An experimental evaluation of the performance of VIEWER in contrast to AltaVista is the major
focus of the paper. We first report the results of an experiment on single, short query searches where VIEWER, used as an
interactive ranking system, markedly outperformed AltaVista. We then concentrate on a more realistic searching scenario, involving
free query formulation, unconstrained selection of retrieval results, and possibility of query reformulation. We report the
results of an experiment where the use of VIEWER, compared to AltaVista, seemed to shift the user effort from inspection to
evaluation of results, increasing retrieval effectiveness, and user satisfaction. In particular, we found that the VIEWER
users retrieved half as many nonrelevant documents as the AltaVista users while retrieving a comparable number of relevant
documents.
Published online: 22 September 2000 相似文献
11.
To improve the discrimination power of color-indexing techniques, we encode a minimal amount of spatial information in the
index. We tesselate each image with five partially overlapping, fuzzy regions. In the index, for each region in an image,
we store its average color and the covariance matrix of the color distribution. A similiarity function of these color features
is used to match query images with images in the database. In addition, we propose two measures to evaluate the performance
of image-indexing techniques. We present experimental results using an image database which contains more than 11,600 color
images. 相似文献
12.
Wen-Syan Li K.Selçuk Candan Kyoji Hirata Yoshinori Hara 《The VLDB Journal The International Journal on Very Large Data Bases》2001,9(4):312-326
Due to the fuzziness of query specification and media matching, multimedia retrieval is conducted by way of exploration.
It is essential to provide feedback so that users can visualize query reformulation alternatives and database content distribution.
Since media matching is an expensive task, another issue is how to efficiently support exploration so that the system is not
overloaded by perpetual query reformulation. In this paper, we present a uniform framework to represent statistical information
of both semantics and visual metadata for images in the databases. We propose the concept of query verification, which evaluates queries using statistics, and provides users with feedback, including the strictness and reformulation alternatives
of each query condition as well as estimated numbers of matches. With query verification, the system increases the efficiency
of the multimedia database exploration for both users and the system. Such statistical information is also utilized to support
progressive query processing and query relaxation.
Received: 9 June 1998/ Accepted: 21 July 2000 Published online: 4 May 2001 相似文献
13.
Steve Jones Shona McInnes Mark S. Staveley 《International Journal on Digital Libraries》1999,2(2-3):207-223
Online information repositories commonly provide keyword search facilities through textual query languages based on Boolean
logic. However, there is evidence to suggest that the syntactic demands of such languages can lead to user errors and adversely
affect the time that it takes users to form queries. Users also face difficulties because of the conflict in semantics between
AND and OR when used in Boolean logic and English language. Analysis of usage logs for the New Zealand Digital Library (NZDL)
show that few Boolean queries contain more than three terms, use of the intersection operator dominates and that query refinement
is common. We suggest that graphical query languages, in particular Venn-like diagrams, can alleviate the problems that users
experience when forming Boolean expressions with textual languages. A study of the utility of Venn diagrams for query specification
indicates that with little or no training users can interpret and form Venn-like diagrams in a consistent manner which accurately
correspond to Boolean expressions. We describe VQuery, a Venn-diagram based user interface to the New Zealand Digital Library
(NZDL). In a study which compared VQuery with a standard textual Boolean interface, users took significantly longer to form
queries and produced more erroneous queries when using VQuery. We discuss the implications of these results and suggest directions
for future work.
Received: 15 December 1997 / Revised: June 1999 相似文献
14.
Approximate query mapping: Accounting for translation closeness 总被引:2,自引:0,他引:2
Kevin Chen-Chuan Chang Héctor García-Molina 《The VLDB Journal The International Journal on Very Large Data Bases》2001,10(2-3):155-181
In this paper we present a mechanism for approximately translating Boolean query constraints across heterogeneous information
sources. Achieving the best translation is challenging because sources support different constraints for formulating queries,
and often these constraints cannot be precisely translated. For instance, a query [score>8] might be “perfectly” translated
as [rating>0.8] at some site, but can only be approximated as [grade=A] at another. Unlike other work, our general framework
adopts a customizable “closeness” metric for the translation that combines both precision and recall. Our results show that
for query translation we need to handle interdependencies among both query conjuncts as well as disjuncts. As the basis, we
identify the essential requirements of a rule system for users to encode the mappings for atomic semantic units. Our algorithm
then translates complex queries by rewriting them in terms of the semantic units. We show that, under practical assumptions,
our algorithm generates the best approximate translations with respect to the closeness metric of choice. We also present
a case study to show how our technique may be applied in practice.
Received: 15 October 2000 / Accepted: 15 April 2001 Published online: 28 June 2001 相似文献
15.
Vincent Aguilera Sophie Cluet Tova Milo Pierangelo Veltri Dan Vodislav 《The VLDB Journal The International Journal on Very Large Data Bases》2002,11(3):238-255
We are interested in defining and querying views in a huge and highly heterogeneous XML repository (Web scale). In this context,
view definitions are very large, involving lots of sources, and there is no apparent limitation to their size. This raises
interesting problems that we address in the paper: (i) how to distribute views over several machines without having a negative
impact on the query translation process; (ii) how to quickly select the relevant part of a view given a query; (iii) how to
minimize the cost of communicating potentially large queries to the machines where they will be evaluated. The solution that
we propose is based on a simple view definition language that allows for automatic generation of views. The language maps
paths in the view abstract DTD to paths in the concrete source DTDs. It enables a distributed implementation of the view system
that is scalable both in terms of data and load. In particular, the query translation algorithm is shown to have a good (linear)
complexity.
Received: November 1, 2001 / Accepted: March 2, 2002 Published online: September 25, 2002 相似文献
16.
When specifying, designing and implementing technology for work, it is very important to consider the whole of the potential
user group, and not to forget that this might include people with disabilities. Obvious reasons for this are demography, disabled
people forming a significant and growing proportion of the workforce, and legal obligations caused by equal opportunities
legislation. There are more subtle reasons, however, which link so-called ‘disabled people’ with the rest of the population.
The paper notes that most people have some disabilities, sometimes temporarily due to accident, or permanently due to ageing
and other processes. In addition it notes that even otherwise fully functioning people can be seriously handicapped by hostile
environments, and a parallel is drawn between the human interface needs of disabled people operating in ordinary situations
and able-bodied people operating in high workload and stress situations. The paper concludes by suggesting a research agenda
for the field on the basis of these considerations. 相似文献
17.
As multimedia applications spread widely, it is crucial for programming and design support systems to handle “time” in multimedia
documents effectively and flexibly. This paper presents a set of interactive system support tools for designing and maintaining
the temporal behavior of multimedia documents. The tool set provides mechanisms for anomaly detection, temporal query processing,
and interactive scheduling. It is based on a fast incremental constraint solver we have developed, which can be adapted by
any constraint-based system. The incremental constraint solver provides immediate feedback to the user, supporting a highly
interactive design process. Combined with existing optimal layout generation mechanisms proposed in the literature, our tools
effectively utilize the flexibility provided by constraint-based systems. 相似文献
18.
Stephan Greene Egemen Tanin Catherine Plaisant Ben Shneiderman Lola Olsen Gene Major Steve Johns 《International Journal on Digital Libraries》1999,2(2-3):79-90
The Human-Computer Interaction Laboratory (HCIL) of the University of Maryland and NASA have collaborated over three years
to refine and apply user interface research concepts developed at HCIL in order to improve the usability of NASA data services.
The research focused on dynamic query user interfaces, visualization, and overview + preview designs. An operational prototype,
using query previews, was implemented with NASA’s Global Change Master Directory (GCMD), a directory service for earth science
datasets. Users can see the histogram of the data distribution over several attributes and choose among attribute values.
A result bar shows the cardinality of the result set, thereby preventing users from submitting queries that would have zero
hits. Our experience confirmed the importance of metadata accuracy and completeness. The query preview interfaces make visible
the problems or gaps in the metadata that are undetectable with classic form fill-in interfaces. This could be seen as a problem,
but we think that it will have a long-term beneficial effect on the quality of the metadata as data providers will be compelled
to produce more complete and accurate metadata. The adaptation of the research prototype to the NASA data required revised
data structures and algorithms.
Received: 12 December 1997 / Revised: June 1999 相似文献
19.
Aya Soffer Hanan Samet 《The VLDB Journal The International Journal on Very Large Data Bases》1998,7(4):253-274
Symbolic images are composed of a finite set of symbols that have a semantic meaning. Examples of symbolic images include
maps (where the semantic meaning of the symbols is given in the legend), engineering drawings, and floor plans. Two approaches
for supporting queries on symbolic-image databases that are based on image content are studied. The classification approach
preprocesses all symbolic images and attaches a semantic classification and an associated certainty factor to each object
that it finds in the image. The abstraction approach describes each object in the symbolic image by using a vector consisting
of the values of some of its features (e.g., shape, genus, etc.). The approaches differ in the way in which responses to queries
are computed. In the classification approach, images are retrieved on the basis of whether or not they contain objects that
have the same classification as the objects in the query. On the other hand, in the abstraction approach, retrieval is on
the basis of similarity of feature vector values of these objects. Methods of integrating these two approaches into a relational
multimedia database management system so that symbolic images can be stored and retrieved based on their content are described.
Schema definitions and indices that support query specifications involving spatial as well as contextual constraints are presented.
Spatial constraints may be based on both locational information (e.g., distance) and relational information (e.g., north of).
Different strategies for image retrieval for a number of typical queries using these approaches are described. Estimated costs
are derived for these strategies. Results are reported of a comparative study of the two approaches in terms of image insertion
time, storage space, retrieval accuracy, and retrieval time.
Received June 12, 1998 / Accepted October 13, 1998 相似文献
20.
Kian-Lee Tan Cheng Hian Goh Beng Chin Ooi 《The VLDB Journal The International Journal on Very Large Data Bases》2000,9(3):261-278
In many decision-making scenarios, decision makers require rapid feedback to their queries, which typically involve aggregates.
The traditional blocking execution model can no longer meet the demands of these users. One promising approach in the literature, called online aggregation, evaluates an aggregation query progressively as follows: as soon as certain data have been evaluated, approximate answers
are produced with their respective running confidence intervals; as more data are examined, the answers and their corresponding
running confidence intervals are refined. In this paper, we extend this approach to handle nested queries with aggregates
(i.e., at least one inner query block is an aggregate query) by providing users with (approximate) answers progressively as
the inner aggregation query blocks are evaluated. We address the new issues pose by nested queries. In particular, the answer
space begins with a superset of the final answers and is refined as the aggregates from the inner query blocks are refined.
For the intermediary answers to be meaningful, they have to be interpreted with the aggregates from the inner queries. We
also propose a multi-threaded model in evaluating such queries: each query block is assigned to a thread, and the threads can be evaluated concurrently and independently.
The time slice across the threads is nondeterministic in the sense that the user controls the relative rate at which these subqueries are being evaluated. For enumerative nested queries, we propose a priority-based evaluation strategy to present answers that are certainly in the final answer
space first, before presenting those whose validity may be affected as the inner query aggregates are refined. We implemented
a prototype system using Java and evaluated our system. Results for nested queries with a level and multiple levels of nesting
are reported. Our results show the effectiveness of the proposed mechanisms in providing progressive feedback that reduces
the initial waiting time of users significantly without sacrificing the quality of the answers.
Received April 25, 2000 / Accepted June 27, 2000 相似文献