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Adapting Video for VI Learners

Design issues and approaches

Video-rich CD-ROM & Web materials

New opportunities

The Web/Internet started life as a predominantly hypertext based system for cross-platform sharing of information. It took off because of three factors:

  • open standards for files. These, being simple text, could be created; edited; and stored on any machine using just that simplest of tools, a text editor;
  • public domain programs (called Browsers) which could interpret these files, the open designs for which ensured that they appeared on all machines; and
  • the connectivity of the Internet.

The popularity of the Web ensured that both browser developers and operating system vendors strove to make access universal.

As the Web's popularity increased, the kinds of media it could handle were soon extended. Graphics were added first, and browsers were enhanced to handle embedded pictures. Then came sound; video; 3-D support and downloadable program fragments. Keeping up with these changes would have been impossible for browser developers. Instead, they took a clever turn, and developed extendible browsers. This meant that as new file formats for new functions were developed, their creators could provide so-called 'plugins' to match their novel products. These freely available subprograms are themselves downloaded over the Internet, and 'clip on' to add to the power of the user's browser.

These plugin media extensions have turned the Web into a massive distributed cross platform open standard multimedia system, with the process of development continuing. Web pages can now contain all the elements of conventional multimedia, together with mail, file transfer, news and other Internet functions not traditionally part of multimedia authoring languages.

Moreover, since file formats and browsers are cross platform, many designers are turning to them as a way of producing non-Web products: information or educational packs delivered on CD-ROM or DVD, or over a local network. The pack you are reading is just such a CD product, with both internal links to its own pages hypertext and multimedia elements, as well as external links to other Web sites. Instead of selecting a particular multimedia vendor's proprietory format, and thus having to use their format-specific multimedia player, the resources you are reading can be viewed on any browser, on any machine, on CD or over the Web. (In principle at least - web speeds, machine power and software updates can conspire against the ideal!).

To confuse matters, technologies are merging and overlapping. For example both Web resources and multimedia share file formats for video: MPEG, AVI and Quicktime can all be sent over the Internet and are supported by browser plugins. Graphics formats are also similar. Even more confusingly, at least one multimedia software vendor has provided a plugin which will let packages developed under their proprietory (and powerful) system to be distributed over the Web and displayed on browsers as though the multimedia asset were just another picture.

What is different about Web - style multimedia?

In the section on multimedia, we described it as

'an amalgam of several technologies bringing together hyperlinked, complex media with specialised program extensions, displaying them under a recognisable metaphor'

and we outlined why such systems are important to developers of materials for VI users. Clearly, those same features - nonlinearity, interactivity, and the ability to modify the user interface, also apply to Web materials. But there are distinctions.

The first is the metaphor. The Web standard file format is a 'hypertext markup language' called HTML. This is a way of telling a browser how text should be displayed: when a line is a heading, when a paragraph is indented, what is a link and where it points to, where a graphic has to go. No matter how much effort designers put into getting away from it, the underlying metaphor is that of a linked set of text pages. If that is what you want, you will find design easy. If on the other hand you want to achieve the kinds of computer based learning, or theatrical metaphors used by other multimedia, you will have to put in more work and the learning curve gets steeper. In particular, you will have to learn to program the browser (usually in a scripting language called JavaScript), and/or you may have to program miniature interfaces of your own called 'Applets' to get what you need.

Then there are the development tools. In a multimedia system, you will find that many of the production tools you need are right there in the package (although video is still usually a separate exercise). But the open standards of the Web mean that you will be developing materials using a raft of different tools - graphics and photo-retouching packages, video capture and editing, web page design, programming and scripting languages, and sound editors. There may be a lot to learn if you are going to stray far from the hypertext - plus - pictures metaphor.

It needn't be so hard...

You may think that given all this, creating materials for VI audiences is too complex. Not so, provided that you adopt a strategy which plays to HTML and its browsers' strengths. The primary decision is to stick with the 'adorned hypertext' metaphor. (If you can't, then conventional multimedia might be the best option). Even within this metaphor there are plenty of opportunities for using multimedia elements - they just won't appear as part of some graphic theatre.

Once you have made this choice, you get some built-in benefits of Web standards for free. Provided you put a little effort into supplying them, hidden text descriptions of pictures and videos will be revealed automatically when the viewer is using a text based browser, or has turned off graphics downloads. More: most browsers let the user choose text fonts, sizes and colours to suit themselves. Once these are chosen, the browser will impose this local user standard over all subsequent pages. Your only task as a designer is to make sure that you don't get in the way of these standard features by overly clever layouts.

If you decide that your users need more support (particularly for highlighting supplementary materials or links, or hiding them from other readers) then programing the browser through JavaScript is probably no harder than learning the scripting languages of multimedia packages.

Making VI-friendly HTML based CD-ROMs

Lets suppose that you decide to develop your video rich materials on a CD-ROM using Web standards. What is the process?

In many ways, the task and the approach is similar to that used for other non-linear multimedia designs. For educational producers with mixed audiences, accessibility still ranks equal with attractiveness. So as always, pay attention to the primary design for each of the media assets and each main web page itself - choose colours, fonts, sizes and so on as you would within any other delivery medium. There are some specific considerations for Web pages. Browsers vary a lot in how they interpret what you specify, so check your production on as many platforms as possible. Design your video clips and graphics with similar restraint. (Several online sources now offer guidance on design for accesibility: see the RNIB, Trace Center, and Magical Mist's sites in our Reference links for some start points)

As with other multimedia, there is usually no difficulty in making space for supplementary pages or diagrams, and the viewer can easily pause a video clip playing on a web page to invoke explanations or explore alternative stills. As before, time constraints for descriptions vanish. The easiest way to provide access to supplementary material is through direct text based hyperlinks off the page, playing to HTML's strengths and as a side-effect making your blind reader's life easier. (If you want to hide those links from other users, use JavaScript to do so, or create duplicate pages with and without extra support elements).

Here is a much abridged description of how to set about development:

  • Choose your tools. You will need a web page design system, and (probably) a graphics package able to export pictures in web formats. You'll definitely need the same video capture and editing systems as for multimedia work. (For the much more ambitious only: scripting support is built into your browser, so you need nothing special for that form of programming).
  • Design your materials to fit the hypertext metaphor
  • Collect all your assets (including the supplementary ones). As with multimedia, your video clips will be different in form to those shot for a continuous programme - terser and more focused on a single aspect.
  • Put the text assets into web pages and form the hyperlinks. At this stage, also insert text descriptions of all the graphical and video elements you aim to include. You can either allow these to emerge naturally through reader choice of text browser, or provide open or hidden links: be consistent.
  • Use a video capture and editing package to convert and compress the video clips: capture and compress other graphical assets;
  • Build links to the video and graphical fragments;
  • Test (and test, and test) and modify;
  • Move the master to CD-ROM, or Recordable CD
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