Databases Reference
In-Depth Information
XML (extensible Markup Language) has become almost
de facto
standard as a
common protocol for exchange of digital documents, and its multimedia
applications such as SVG, X3D, VoiceXML, and SMIL have been developed.
However, as application areas are enlarging, we meet more restrictions of XML: for
example, from a data model pont of views such as complex objects and semistructured
data, from viewpoints of combination of shared and personal information, and
from viewpoints of integration of multimedia information. It is indispensable to
relax such restrictions for advanced applications with electronic documents.
Further, from a user point of view, multimedia documents should be interactive
to users, because users want to read through a forest of multimedia information.
We are now engaged in heterogeneous document management
Kunishima et al 99),
digital
theme parks
Liu et al 00)
, interactive synchronous presentation of multimedia
information
Fujino et al 00)
, literature databases
Miyake et al 00)
, and so on, where we require
extensions of XML and interactive presentation of multimedia information, and
have implemented their prototype systems.
In this article, we discuss relaxation of such restrictions, or semantic extensions
of XML, and interactive multimedia presentation. We report our approaches to
their problems.
First, we discuss heterogeneities in management of digital documents and
requirements of extensions of XML in Section 2. Secondly, we discuss interactive
presentation of multimedia documents, especially authoring facilities, in Section
5. Thirdly, we propose a model of semantic extensions of XML in Section 3, its
architecture for interactive presentation in Section 5, and introduce an
implementation of our prototype systems in Section 4. Lastly we summarize their
technologies in Section 6.
2
Approachs to Management of Heterogeneous Documents
Consider that we write a paper in . It is compiled into a dvi file. The dvi file
is tranformed into a postscript file for printing and into a pdf file for online
publication. We sometimes write an oral manuscript and prepare a PowerPoint
file for presentation. Although their contents are the same, we have to produce
various files.
There are various heterogeneities in digital documents:
•
We can represent documents in various data format such as plain text ,
postscript, PDF, MS Word, MS PowerPonit, HTML, and XML. To manage
their content-based relationships, we have to consider links between objects
in various formats.
•
As we want to write personal information even in a shared document, the
documents must be viewed with different contents from each user. There
may be some shared levels: not only personal but also group levels, and we
can consider a shared hierarchy and view mechanisms according to some
purposes.
