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614 lines
26 KiB
614 lines
26 KiB
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
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<HTML>
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<HEAD>
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<META name="RCS-Id" content="$Id: NOTE-SYMM-modules-19990223.html,v 1.2 1999/02/23 19:58:44 renaudb Exp $">
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<META content="text/xhtml; charset=iso-8859-1" http-equiv="Content-Type">
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<TITLE>Modularization of Synchronized Multimedia Functionality</TITLE>
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<LINK rel="stylesheet" type="text/css" media="screen" href="/StyleSheets/TR/W3C-NOTE.css">
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</HEAD>
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<BODY>
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<DIV class="head">
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<P><A href="http://www.w3.org/"><IMG height="48" width="72" src="/Icons/WWW/w3c_home"
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alt="W3C"></A></P>
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<H1>Synchronized Multimedia Modules<BR>
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based upon SMIL 1.0
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</H1>
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<H2>
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W3C Note 23 February 1999
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</H2>
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<TABLE>
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<TR valign="baseline">
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<TD>This version:
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<TD><A class="loc" href="http://www.w3.org/TR/1999/NOTE-SYMM-modules-19990223">http://www.w3.org/TR/1999/NOTE-SYMM-modules-19990223</A>
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<TR valign="baseline">
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<TD>Latest version:
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<TD><A class="loc" href="http://www.w3.org/TR/NOTE-SYMM-modules">http://www.w3.org/TR/NOTE-SYMM-modules</A>
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<TR valign="baseline">
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<TD>Editors:
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<TD><SPAN class="author"><SPAN class="name">Patrick Schmitz</SPAN>
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<I>(<SPAN class="email"><A href="mailto:pschmitz@microsoft.com">pschmitz@microsoft.com</A></SPAN>)</I></SPAN><BR>
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<SPAN class="author"><SPAN class="name">Ted Wugofski</SPAN>
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<I>(<SPAN class="email"><A href="mailto:Ted.Wugofski@OTMP.com">Ted.Wugofski@OTMP.com</A></SPAN>)</I></SPAN><BR>
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<SPAN class="author"><SPAN class="name">Warner ten Kate</SPAN>
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<I>(<SPAN class="email"><A href="mailto:tenkate@natlab.research.philips.com">tenkate@natlab.research.philips.com</A></SPAN>)</I></SPAN>
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</TABLE>
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<P class="copyright"><A href="http://www.w3.org/Consortium/Legal/ipr-notice#Copyright">
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Copyright</A> © 1999 <A href="http://www.w3.org/">W3C</A>
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(<A href="http://www.lcs.mit.edu/">MIT</A>,
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<A href="http://www.inria.fr/">INRIA</A>,
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<A href="http://www.keio.ac.jp/">Keio</A>), All Rights Reserved. W3C
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<A href="http://www.w3.org/Consortium/Legal/ipr-notice#Legal_Disclaimer">liability</A>,
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<A href="http://www.w3.org/Consortium/Legal/ipr-notice#W3C_Trademarks">trademark</A>,
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<A href="http://www.w3.org/Consortium/Legal/copyright-documents">document
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use</A> and
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<A href="http://www.w3.org/Consortium/Legal/copyright-software">software
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licensing</A> rules apply.
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</DIV>
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<HR title="Separator from Header">
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<H2>
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Status of this document
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</H2>
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<P>
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This Note was produced by the W3C SYMM Interest Group. It describes a snapshot
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of certain aspects of the discussions on future work on SYMM and SMIL. Following
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the approach spearheaded by the W3C HTML Working group, the Note describes
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how SMIL 1.0 functionality and future SYMM functionality can be represented
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as a set of markup modules. The intention was to study the feasibility of
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such an approach, and the details of the proposed modularisation are preliminary
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only. Please send comments to the public mailing list
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<A HREF="mailto:www-smil@w3.org">www-smil@w3.org</A>.
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<P>
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This document is a NOTE made available by W3C for discussion only. This indicates
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no endorsement of its content, nor that W3C has, is, or will be allocating
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any resources to the issues addressed by the NOTE.
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<H2>
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Table of Contents
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</H2>
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<DL>
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<DD>
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<A href="#Abstract">Abstract</A>
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<DD>
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<A href="#Introduction">1. Introduction</A>
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<DD>
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<A href="#SymmModules">2. Synchronized Multimedia Modules</A>
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<DD>
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<A href="#ModuleIntegration">3. Module Integration</A>
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<DD>
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<A href="#Profiles">4. Multimedia Profiles</A>
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<DD>
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<A href="#Issues">5. Issues</A>
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<DD>
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<A href="#refs">References</A>
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</DL>
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<H2>
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<A name="Abstract">Abstract</A>
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</H2>
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<P>
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<I>This document describes a proposed modularization of synchronized multimedia
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functionality, based upon the SMIL 1.0 Recommendation. The proposed
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modules complement HTML/CSS modules to support the definition of multimedia
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profiles that combine SYMM and HTML/CSS modules, as well as other XML-based
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languages. A set of example profiles for multimedia use is described.
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The document is intended to form a basis for work by a future SYMM Working
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Group.</I>
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<H2>
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<A name="Introduction">1. Introduction</A>
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</H2>
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<P>
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The first W3C Working Group on Synchronized Multimedia (SYMM) developed
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<A href="#ref-SMIL">SMIL</A> - Synchronized Multimedia Integration Language.
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This XML-based language is used to express synchronization relationships
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among media elements. SMIL 1.0 documents describe multimedia presentations
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that can be played in SMIL-conformant viewers.
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<P>
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SMIL 1.0 provides limited means for integrating with HTML, CSS or other XML
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languages. This integration has been an area of considerable interest
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within the W3C as well as other external organizations (such as the
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<A href="http://www.atsc.org">ATSC T3/S17</A> specialist group). The
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<A href="http://www.w3.org/AudioVideo/">W3C SYMM Interest Group</A> has been
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tracking these issues in preparation for future work on the SMIL language..
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<P>
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The <A href="http://www.w3.org/MarkUp/">W3C HTML Working Group</A> is working
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towards a modularization of HTML. The
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<A href="http://www.w3.org/Style/CSS/">W3C CSS Working Group</A> has had
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similar discussions. One reason that the HTML Working Group is pursuing
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modularization is to support the use of HTML in a wider range of applications.
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In support of this activity, the HTML Working Group and the SYMM Interest
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Group have been discussing strategies for integrating multimedia functionality
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into HTML. Several proposals have been submitted and are being discussed
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(<A href="#ref-HTML+TIME">HTML+TIME</A> and <A href="#ref-BHTML">BHTML</A>).
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One approach to solving this problem is to modularize synchronized multimedia
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functionality, and make these modules available to other languages.
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<H3>
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1.1. Goals and Requirements
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</H3>
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<P>
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There are four goals for modularizing synchronized multimedia functionality:
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<UL>
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<LI>
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<EM>G1</EM>: provide a means for the W3C and third parties to integrate timing
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models into other languages (such as HTML).
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<LI>
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<EM>G2</EM>: provide a means for the W3C to extend SMIL with new or optional
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features.
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<LI>
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<EM>G3</EM>: provide a means for third parties to extend SMIL with
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domain-specific features.
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<LI>
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<EM>G4</EM>: provide a means for third parties to integrate other languages
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into SMIL applications.
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</UL>
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<P>
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In essence, modularizing SMIL is the first step towards the integration of
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timing and other key aspects of SMIL with other Web languages. This
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modularization provides a means for other languages, such as HTML and an
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XML-based vector-graphics format, to benefit from timing and synchronization
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functionality while reusing the lessons learned and work embodied in SMIL.
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This becomes especially important for the development of cross-language tools
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which can readily transcode syntax but generally have a difficult time porting
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content to different timing and content models.
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<P>
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This Note describes the current approach to this problem by the SYMM Interest
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Group. The modules described herein satisfy the following design requirements:
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<UL>
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<LI>
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<EM>R1</EM>: modularize SMIL 1.0 without meaningful changes to the SMIL 1.0
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content model.
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<LI>
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<EM>R2</EM>: modularize SMIL 1.0 without meaningful changes to the SMIL 1.0
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timing model.
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<LI>
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<EM>R3</EM>: specify SMIL 1.0 modules that complement HTML modules.
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<LI>
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<EM>R4</EM>: adopt new W3C recommendations when appropriate and not in conflict
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with other requirements.
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</UL>
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<P>
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Several additional requirements will inform the work of a future SYMM working
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group:
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<UL>
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<LI>
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<EM>R5</EM>: All of the modules should have integrated support for the document
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object model. This facilitates additional control via script and custom
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user agents (e.g. for playback controls). Support for the respective
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object model is optional for all profiles. In designing the object
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model for facilitating script control, it should be investigated whether
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declarative solutions can also be provided, and, where possible, be specified.
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<LI>
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<EM>R6</EM>: Interfaces should be defined that provide means for
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integration between 3rd party player/renderers and browser engines.
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Time-based behaviors of browsers should also be available to 3rd party
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player/renderers. For example, applications may interface with a HTML renderer
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and with an independent audio and video renderer. The result should
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be tightly integrated multimedia presentations.
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<LI>
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<EM>R7</EM>: Where practical, modules should be defined isomorphic with modules
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from other W3C recommendations. This will assist module sharing across
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profiles. Targetting for isomorphic modules requires bilateral
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cooperation. Alignment of overlap in functionality concerns in particular
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the HTML module definitions.
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<LI>
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<EM>R8</EM>: It must be possible to define a profile that is 100% backwards
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compatible with SMIL 1.0.
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<LI>
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<EM>R9</EM>: For the purpose of integration with other profiles, modules
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may take another syntax. However, it is required that the semantics are
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maintained.
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</UL>
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<P>
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The purpose of the requirements is to ensure that the modularization makes
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no significant changes to the SMIL 1.0 language while laying a foundation
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for integration with HTML, CSS, and other Web Languages. This Note provides
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a discussion of current integration strategies and proposals.
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<P>
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The SYMM Interest Group recommends that the results presented in this Note
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form the basis for some of the work of a future SYMM Working Group.
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<H3>
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1.2. Modules and Profiles
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</H3>
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<P>
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Modularization of synchronized multimedia functionality provides a building
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block for language, application, and platform developers. This Note recognizes
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that in addition to functional modules, there exists the notion of profiles
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and platforms.
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<P>
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For the purposes of this Note, we define the terms <EM>module</EM>,
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<EM>profile</EM>, and <EM>platform</EM>:
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<DL>
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<DT>
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<EM>module</EM>
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<DD>
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A module is a collection of elements. Each element is in one and only one
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module.
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<DT>
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<EM>profile</EM>
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<DD>
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A profile is a collection of modules particular to an application domain
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or language. For example: The SMIL profile corresponds to the collection
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of modules that make up the SMIL language. A enhanced television profile
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would correspond to the collection of modules for media-enhancement of broadcast
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television.
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<DT>
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<EM>platform</EM>
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<DD>
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A platform is a collection of profiles, non-Web technologies, policies, resource
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requirements, etc.
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</DL>
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<P>
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This Note focuses on modules and profiles, and is not concerned with specifying
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or characterizing platforms. Nevertheless, it is worth noting the distinction
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between a profile and a platform: a profile generally describes a <EM>document
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type</EM> and its usage, whereas a platform encompasses the <EM>entire
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environment</EM>. (The term "profile" as defined by the HTML WG is likely
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to bear a wider scope than used in this Note.)
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<H2>
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<A name="SymmModules">2. Synchronized Multimedia Modules</A>
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</H2>
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<P>
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This Note proposes a set of modules for SYMM functionality. The first
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section describes the modules associated with functionality defined in SMIL
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1.0. A second section describes proposed extensions to SMIL 1.0.
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<H3>
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2.1. SMIL 1.0 Modules
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</H3>
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<DL>
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<DT>
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<STRONG>Structure</STRONG>
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<DD>
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Includes the <smil>, <head> and <body> elements.
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These elements will be used in documents based upon traditional SMIL profiles.
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<DT>
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<DT>
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<STRONG>Meta</STRONG>
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<DD>
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Includes the <meta> element. The elements contain information describing
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the document, either to inform the human user or to assist some automation.
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The element will be used in documents based upon traditional SMIL profiles,
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possibly in concert with meta data modules available from other efforts.
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<DT>
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<DT>
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<STRONG>Layout</STRONG>
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<DD>
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Includes the <layout>, <root-layout> and <region> elements,
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and related attributes. This module supports the layout mechanism described
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in SMIL 1.0. These elements will all be used in documents based upon
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the SMIL profile.
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<DT>
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<DT>
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<STRONG>Timing and Synchronization markup</STRONG>
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<DD>
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This module includes timing structure (e.g. sequence and parallel timelines)
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and timing control properties (e.g. begin, end, and repeat) that describe
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the timing relationships among elements. This module also includes
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mechanisms to control the <EM>performed </EM>synchronization of the document
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(described in SMIL 1.0 as soft and hard).<BR />
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This is separated from the media so that it can be applied to HTML and XML
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applications independent of support for media. <BR />
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Note that in some integration profiles, the specific <EM>syntax</EM> for
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the markup may vary slightly with the profile (e.g. the SMIL 1.0
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<seq> element may be represented as a sequence attribute if a CSS
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style-based integration is used). These differences notwithstanding,
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the module <EM>semantics</EM> and the <EM>timing model</EM> will be consistent
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across all profiles. <BR />
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The specific syntax and mechanism of integration with HTML and XML applications
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is under review.
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<DT>
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<DT>
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<STRONG>Media Elements</STRONG>
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<DD>
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This includes the media declaration elements <ref>,
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<animation>, <audio>, <img>, <video>, <text>
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and <textstream>. The media declaration may relate to the object
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element in HTML (this needs attention).
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<DT>
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<DT>
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<STRONG>Linking</STRONG>
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<DD>
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Includes the <a> and <anchor> elements.<BR />
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The relation of this module to other linking modules, particularly XLink,
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XPointer and HTML linking, is under review. For example when integrating
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with HTML, timing applied to the (HTML) <a> and <area> elements
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could provide much or all of the SMIL 1.0 defined functionality.
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<DT>
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<DT>
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<STRONG>Content control</STRONG>
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<DD>
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This includes the <switch> element and test attributes introduced in
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SMIL 1.0. This is of general utility to authors, independent of the
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multimedia functionality.
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</DL>
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<H3>
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2.2. Proposed Extensions
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</H3>
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<DL>
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<DT>
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<STRONG>Layout</STRONG> (extensions)
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<DD>
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Additional functionality will likely be added to this module as part of ongoing
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work. Relationship of this Layout module to other Layout mechanisms,
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including CSS, is to be considered.
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<DT>
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<DT>
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<STRONG>Timing and Synchronization markup</STRONG> (extensions)
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<DD>
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Additional functionality will likely be added to the module as part of ongoing
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work. Proposed extensions include event-based timing constructs, e.g.
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to support user-interaction and stream events, and more detailed mechanisms
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to control the <EM>performed </EM>synchronization of the document.
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<DT>
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<DT>
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<STRONG>Transitions</STRONG>
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<DD>
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This module includes new functionality to support transition effects on
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elements. These may be media elements, or they may be traditional HTML
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(or XML) elements. A CSS-style syntax under consideration might represent
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transitions as in this HTML-based example:<BR />
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<PRE><html>
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<head>
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<title>Powerpoint Animation in HTML</title>
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<style>
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p.caption { transition-style: wipe; font-size: big }
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li { transition-style: dissolve }
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</style>
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</head>
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<body>
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<p class="caption">Multimedia Requirements</p>
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<ul>
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<li>Timing the Display of Bullet Items</li>
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<li>Transition Effects</li>
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</ul>
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</body>
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</html>
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</PRE>
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<P>
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Specifics of the module syntax is under review. There is a desire to
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present a simple syntax for typical use-cases, and also to support more complex
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functionality by modeling transitions as filters with timing support. The
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various proposals will be considered and refined as work proceeds.
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<DT>
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<STRONG>Animation</STRONG>
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<DD>
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This module includes functionality to support common simple animation like
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motion paths. Where Transitions apply rendering filters, Animation
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behaviors manipulate Object Model properties like position, color, size or
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rotation (e.g. in an XML-based vector-graphics format).
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<DT>
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<DT>
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<STRONG>Resource Management</STRONG>
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<DD>
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This module includes support for resource (e.g. bandwidth) management
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hints. These can facilitate user agent optimizations, and can control
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the degradation strategy of the user agents. For example, the author
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may assign priorities to elements to inform a user-agent that will dynamically
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balance network bandwidth. Other proposed markup includes hints for cueing
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or preloading media and a means of specifying that an individual media element
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is delivered as a substream within an aggregated media stream (for large
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streamed presentations).
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</DL>
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<H2>
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<A name="ModuleIntegration">3. Module Integration</A>
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</H2>
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<P>
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The HTML Working Group is still reviewing formal mechanisms to define or
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specify profiles. Several approaches are under consideration including
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DTDs, XML Schemas, and RDF-based mechanisms. The SYMM Activity will
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provide associated requirements and use-cases to the HTML Working Group,
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and will follow the recommendation of the HTML Working Group for profile
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specification.
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<P>
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Several mechanisms for integrating SYMM functionality with other languages
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(especially HTML) have been discussed. It is possible that a given
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module may be represented with different syntax depending upon the profile
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and integration. Nevertheless, the SYMM modules will define consistent
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<EM>semantics </EM>for all profiles, regardless of syntax variants.
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<P>
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The current variants and issues for integrating synchronized multimedia
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functionality with HTML and XML languages are:
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<UL>
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<LI>
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Defining tagsets for SMIL elements. This is a yes/no choice, and combines
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with the others. I.e. A profile can either:
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<UL>
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<LI>
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Define XML tags for SMIL elements together with SMIL attributes (as specified
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with one of the mechanisms below), <STRONG>or</STRONG>
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<LI>
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Define only attributes. All SMIL elements would be represented as attributes
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(of some sort) applied to HTML elements.
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</UL>
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<P>
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At issue in particular are the SMIL timing structure elements <par>
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and <seq>, which could be expressed as an attribute on HTML (or XML)
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container elements. While this is expressed as a dichotomy, it really defines
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a range of possibilities. Profiles may map <EM>some </EM>elements to
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attributes and leave others as elements.
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<LI>
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Attribute Syntax variants
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<DL>
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<DT>
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<STRONG>XML Namespace qualified attributes</STRONG>
|
|
<DD>
|
|
This has the advantage of general applicability to any XML language. It has
|
|
the disadvantage that it is impossible to set the value of an XMLNS attribute
|
|
via CSS stylesheets without defining a CSS property that corresponds to the
|
|
XMLNS attribute.
|
|
<DT>
|
|
<STRONG>CSS properties </STRONG>
|
|
<DD>
|
|
This has the advantage that stylesheets can be used to define timing,
|
|
transitions, etc. It the disadvantage that it requires CSS, which may
|
|
not be appropriate for some XML languages or for some profiles and platforms.
|
|
<DT>
|
|
<STRONG>XSL properties</STRONG>
|
|
<DD>
|
|
This is a variant on CSS properties, but would support a broader range of
|
|
XML applications.
|
|
</DL>
|
|
</UL>
|
|
<H2>
|
|
<A name="Profiles">4. Multimedia Profiles</A>
|
|
</H2>
|
|
<P>
|
|
A range of profiles have been discussed that would make use of different
|
|
sets of modules. Below is an initial list of profiles that could integrate
|
|
SYMM and HTML functionality in different ways. This is not intended
|
|
to be a final statement, but rather an indication of how modules would be
|
|
used. It provides a backdrop for the discussion of modularization.
|
|
<P>
|
|
In addition, some specific proposals can be described in terms of the relevant
|
|
modules:
|
|
<UL>
|
|
<LI>
|
|
<A href="#ref-SMIL">SMIL 1.0</A> would be defined as the 1.0 versions
|
|
of the Structure, Meta, Layout , Timing, Media, Linking, and Content control
|
|
modules. SMIL 2.0 would include all of the new versions of these modules,
|
|
as well as some or all of the new modules proposed.
|
|
<LI>
|
|
<A href="#ref-HTML+TIME">HTML+TIME</A> proposes a profile that extends an
|
|
HTML 4.0 profile to include Timing, Media, Linking and Content control
|
|
modules.
|
|
<LI>
|
|
<A href="#ref-BHTML">BHTML</A> proposes a profile that similarly extends
|
|
HTML to include Timing, Media and Linking, as well as Transition support.
|
|
</UL>
|
|
<H3>
|
|
4.1. Example Profiles
|
|
</H3>
|
|
<DL>
|
|
<DT>
|
|
<STRONG>Leightweight presentations</STRONG>
|
|
<DD>
|
|
A basic profile would handle simple presentations, supporting timing of text
|
|
content. The simplest version of this could be used to sequence stock quotes
|
|
or headlines on restricted <EM>platforms </EM>like palmtop devices or smart
|
|
phones. The <A href="http://www.w3.org/Mobile/">Mobile Access group</A>
|
|
is looking at related profiles. An HTML-based profile would combine
|
|
HTML modules (probably a subset of HTML) with the timing module. It might
|
|
include the transitions as well.
|
|
<DT>
|
|
|
|
<DT>
|
|
<STRONG>Timeline-Centric Multimedia presentations</STRONG>
|
|
<DD>
|
|
This describes the profile associated most closely with SMIL 1.0. This
|
|
does not integrate HTML, and uses SMIL layout rather than the flow layout
|
|
model associated with HTML . Typical use-cases for this profile are
|
|
multimedia presentations that include time-based and streaming media. This
|
|
would include most or all of the SMIL modules.
|
|
<DT>
|
|
|
|
<DT>
|
|
<STRONG>HTML integrated Multimedia presentations</STRONG>
|
|
<DD>
|
|
This is a variant on the Traditional Multimedia profile that mixes multimedia
|
|
and HTML. It mixes HTML layout (i.e. flow layout) and CSS
|
|
positioning. Use-cases for this profile are presentations that use
|
|
HTML as a media type in concert with time-based and streaming media (e.g.
|
|
PowerPoint-like presentations with time-based media). This profile would
|
|
include (most or all of) the HTML modules, the Timing, Media, Transition,
|
|
Animation, Resource Management and Content control modules (i.e. all but
|
|
the Structure, Meta and Layout modules). The linking functionality
|
|
would overlap between the Linking module and a similar HTML module.
|
|
<DT>
|
|
|
|
<DT>
|
|
<STRONG>Web Enhancement of Broadcast, On-Demand Video and DVD</STRONG>
|
|
<DD>
|
|
This describes support for web presentations tied to broadcast and/or on
|
|
demand media. The primary media will often define the main timeline.
|
|
The main additional requirements here are for stream event support and the
|
|
ability to tie the page clock to the primary media. Stream event support
|
|
requires event-based timing of elements (and timelines), and a means of
|
|
associating events with document-external (stream) triggers. E.g. where the
|
|
stream could be a TV-broadcast, it would be possible to refer to the events
|
|
by referencing the TV broadcast stream or player-object. It must be
|
|
possible to ensure that the multimedia (enhancement) timeline is strictly
|
|
synced to or driven by the primary (broadcast) media.<BR />
|
|
<BR />
|
|
Note that where "webcasting" may associate Web-pages to a TV-broadcast, in
|
|
"enhanced television" additional media form an integral part with the main
|
|
video presentation, providing enhancement of and interaction with the program.
|
|
<BR />
|
|
<BR />
|
|
While the typical use-cases may be dominated with the primary media (e.g.
|
|
streaming video broadcast or DVD video), the authoring model is still closely
|
|
tied to the Web and HTML. This profile would likely use the same modules
|
|
as the HTML integrated Multimedia presentations profile, but with the additional
|
|
timing and synchronization requirements described.
|
|
</DL>
|
|
<H2>
|
|
<A name="Issues">5. Issues</A>
|
|
</H2>
|
|
<H4>
|
|
Syntax
|
|
</H4>
|
|
<P>
|
|
The details of the elements and properties still need to be worked out.
|
|
In particular, there are open issues on the syntax for timing markup, and
|
|
the mechanism for integration with HTML and XML applications, and stylesheet
|
|
tools like CSS and XSL.
|
|
<H4>
|
|
Accessibility syntax
|
|
</H4>
|
|
<P>
|
|
An additional issue that must be coordinated with representatives of the
|
|
Web Accessibility Initiative (WAI) concerns accessibility support.
|
|
This includes elements and attributes which assist the accessibility of content
|
|
declared in the presentation. In SMIL 1.0, this concerns the title, alt and
|
|
longdesc attributes.
|
|
<P>
|
|
It is not clear whether this should be an additional module, or additional
|
|
support in specific modules. In particular, the intent is not to define
|
|
a new set of Accessibility mechanisms, but to integrate current work of expert
|
|
groups in this area.
|
|
<P>
|
|
<HR />
|
|
<H2>
|
|
<A name="refs">References</A>
|
|
</H2>
|
|
<DL>
|
|
<DT>
|
|
<A href="http://toocan.philabs.research.philips.com/misc/atsc/bhtml/" name="ref-BHTML">Broadcast
|
|
HTML</A>
|
|
<DD>
|
|
A Modular Hypertext Markup Language for Broadcast Applications. HTML working
|
|
group contributed paper. Ted Wugofski. This is available at:
|
|
http://toocan.philabs.research.philips.com/misc/atsc/bhtml/
|
|
<DT>
|
|
<A href="http://www.w3.org/TR/NOTE-HTMLplusTIME" name="ref-HTML+TIME">HTML+TIME</A>
|
|
<DD>
|
|
Timed Interactive Multimedia Extensions for HTML (HTML+TIME) Note 18 September
|
|
1998, Patrick Schmitz, Jin Yu, Peter Santangeli. This is available at:
|
|
http://www.w3.org/TR/NOTE-HTMLplusTIME
|
|
<DT>
|
|
<A href="http://www.w3.org/TR/1998/WD-html-in-xml-19981205/" name="ref-HTMLinXML">Reformulating
|
|
HTML in XML</A>
|
|
<DD>
|
|
W3C Working Draft 5 December 1998, Dave Raggett, Frank Boumphrey, Murray
|
|
Altheim, Ted Wugofski. This is available at:
|
|
http://www.w3.org/TR/1998/WD-html-in-xml-19981205
|
|
<DT>
|
|
<A href="http://www.w3.org/TR/REC-smil" name="ref-SMIL">SMIL 1.0</A>
|
|
<DD>
|
|
Synchronized Multimedia Integration Language (SMIL) 1.0 Specification 15
|
|
June 1998, Philipp Hoschka. This is available at: http://www.w3.org/TR/REC-smil
|
|
</DL>
|
|
</BODY></HTML>
|