XML Modules

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XML Modules

• Extending Web Accessibility

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W3C Web Accessibility Initiative (WAI)

• "The power of the Web is in its universality.
  Access by everyone regardless of disability is an
  essential aspect."
• -- Tim Berners-Lee, W3C Director and inventor
  of the World Wide Web

W3C World Wide Web Consortium
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What Is an XML Module?

• An XML module is a collection of
  semantically-related XML elements and attributes
  oriented toward accomplishing a certain task or
  function.
• An excellent example of modularization is the
  manner in which the W3C has organized into
  modules the various parts of the Synchronized
  Multimedia Implementation Language (SMIL).
• SMIL is an XML-based language that was created by
  the W3C for the purpose of enabling developers to
  include multimedia events in Web documents.

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There are 10 SMIL Modules

• Timing
• Time Manipulations
• Animation
• Content Control
• Layout

• Linking
• Media objects
• Metainformation
• Structure
• Transitions

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What Is a Language Profile?

• A language profile is the combination of modules
  to create an XML language designed to meet
  certain objectives.
• The W3C has created a language profile, for
  example, for the purpose of adding multimedia
  functionality to XHTML.
• The name of this profile is XHTMLSMIL.
• Its goal is to permit the Web designer to use
  SMIL animations, timings, and transitions within
  a conventional HTML or CSS page layout.
• Thus, XHTMLSMIL omits modules related to layout.
• As a result, the Web designer can create a layout
  via style sheets or HTML and include SMIL
  animations, timings, and transitions in
  traditional Web page elements.

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What Is HTMLTIME?

• Microsoft has created an implementation of
  XHTMLSMIL called HTMLTIME, which works with
  Internet Explorer versions 5.5 and later.
• True to its name, the most important part of
  HTMLTIME is the timing module, because that is
  how you create synchronized multimedia events.
• An excellent example of a multimedia event that
  requires timing is the captioning of a video,
  which requires you to display onscreen subtitles
  at precise times in sync with the video.

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Captioning a Video with SMIL

• The SMIL timing module contains a seq tag that
  enables you to sequence multimedia events.
• The tag name ltseqgt stands for sequence.
• You can use the seq tag to create video captions.

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The Moon Challenge

• President John F. Kennedys Moon Challenge video
  is at the course Web site.
• Its URL is
• www.udel.edu/awd/movies/KennedyMoonChallenge.avi
• Let us view it captioned.

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How the Captioning Works

• First, we modify the HTML tag to bind in the Time
  namespace
• ltHTML xmlnst"urnschemas-microsoft-comtime"gt
  
• Then we make the page use Time version 2
• ltSTYLEgt
• .time behavior url(defaulttime2)
• lt/STYLEgt

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Playing the Video

• In the body of the page, the first row of a table
  plays the video
• ltTABLE CELLSPACING"0" STYLE"background-colorWhi
  tefontboldfont-size11pt"gt
• ltTRgt
• ltTDgt
• lttVIDEO CLASS"time" ID"movie"
• SRC"KennedyMoonChallenge.avi" /gt
• lt/TDgt
• lt/TRgt

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Captioning the Video

• The second row of the table captions the video as
  it plays
• ltTRgt
• ltTD ID"caption" STYLE"background-color
  White" ALIGN"center"gt
• lttSEQ ID"txSeq" CLASS"time
  BEGIN"movie.begin.5"gt
• ltSPAN ID"1" CLASS"time" tDUR"2"gtWe
  choose to go to the moon inlt/SPANgt
• ltSPAN ID"2" CLASS"time" tDUR"2.5"gtthis
  decade and do the other things,lt/SPANgt

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Captioning the Video(continued)

• ltSPAN ID"3" CLASS"time" tDUR"2.15"gtnot
  because they are easy,lt/SPANgt
• ltSPAN ID"4" CLASS"time" tDUR"2.0"gtbut because
  they are hard.lt/SPANgt
• ltSPAN ID"5" CLASS"time" tDUR"1.8"gtBecause
  that goallt/SPANgt
• ltSPAN ID"6" CLASS"time" tDUR"1.8"gtwill serve
  to organizelt/SPANgt
• ltSPAN ID"7" CLASS"time" tDUR"1.8"gtand measure
  the bestlt/SPANgt
• ltSPAN ID"8" CLASS"time" tDUR"2.2"gtof our
  energies and skills.lt/SPANgt
• ltSPAN ID"9" CLASS"time" tDUR"2.1"gtBecause
  that challenge is onelt/SPANgt
• ltSPAN ID"10" CLASS"time" tDUR"1.9"gtthat we're
  willing to accept,lt/SPANgt
• ltSPAN ID"11" CLASS"time" tDUR"2.2"gtone we are
  unwilling to postpone,lt/SPANgt
• ltSPAN ID"12" CLASS"time" tDUR"2.3"gtand one we
  intend to win,lt/SPANgt
• ltSPAN ID"13" CLASS"time" tDUR"3"gtand the
  others too.lt/SPANgtlt/tSEQgt
• lt/TDgt
• lt/TRgt
• lt/TABLEgt