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The CPB/WGBH National Center for Accessible Media (NCAM) is a research and development facility dedicated to issues of media technology for disabled people in their homes, schools, workplaces, and communities. NCAM's mission is to expand access to present and future media for people with disabilities; to explore how existing access technologies may benefit other populations; to represent its constituents in industry, policy and legislative circles; and to provide access to educational and media technologies for special needs students.
Access to Rich Media Project
The Access to Rich Media project is in its third and final year. The project strives to ensure that Americans who are deaf, hard-of-hearing, blind, or have low vision are able to effectively use rich media. The project is working toward this end via two goals:
The Access to Rich Media project funding is provided by NIDRR, the National Institute on Disability and Rehabilitation Research (http://www.ed.gov/offices/OSERS/NIDRR) in the U.S. department of Education, and has technology partners such as Apple, Real, Microsoft, the W3C, Oratrix, Macromedia, and multiple content partners such as PBS's NOVA and the Library of Congress.
What is Rich Media?
Rich Media refers to elements on a Web page (or in a standalone player application) which exhibit change over time or in response to user interaction.
One obstacle to making rich media accessible is a lack of basic knowledge of the needs of blind, visually impaired, deaf, and hearing impaired users on the part of content providers. The W3C's Web Content Accessibility Guidelines(3) and Section 508 regulations(4) have helped raise awareness, but even developers and content providers aware of the issues often need additional information, tools, and models to help them implement solutions for their own content.
Another obstacle is a lack of specific technical knowledge related to accessibility on the part of multimedia developers. New versions of Macromedia Flash and Authorware have the ability to deliver information to screen readers, but of the small number of developers who are aware that such capabilities exist in these and other tools, few know how to use the features resulting in accessible rich media.
Access for people who are deaf or hearing impaired
Without captions, rich media that incorporates sound is likely to be inaccessible to deaf or hearing impaired users, since sound often plays an important role in communicating the author's message in rich media. The ability to create and add captions to many forms of online media holds promise for people who are deaf or hearing impaired. Players such as QuickTime, Windows Media, Real and Internet Explorer all have the ability to display captions built in.
There are currently three major methods of creating and displaying captions in multimedia Ñ Apple's QuickTime, MicrosoftÕs Synchronized Accessible Media Interchange (SAMI) format, and the World Wide Web Consortium's Synchronized Multimedia Integration Language (SMIL). None of these methods can fully enable real-time captioning display or description output and none of these technologies can import analog television's line-21 closed caption data. All three of these methods have limitations, which frustrate designers interested in creating accessible multimedia and frustrate consumers who must rely on these features. Equally disheartening, none of these access technologies are being used to any extent by Web designers to provide access.
NCAM has responded to these issues in two significant ways: first, the development of version 2.01 of MAGpie, an application for creating captions and audio descriptions, to address the need for easy-to-use tools for creating captions; and second, the development of a rich media accessibility Web site, which includes a showcase of examples of media with different sorts of captions and a learning area where developers can learn specific techniques to assist their work in creating captions.
Visitors to the Rich Media Accessibility Web site's showcase can view examples of captions in QuickTime, Real, Windows Media, Internet Explorer, and Macromedia Flash, and learn about different types of captions (pop-on, roll-up, etc.).
No solution is perfect, and each captioning technology is proof of this. There are a wide variety of issues that affect how captions are displayed, including the operating system and player or browser version. For example, QuickTime captions made by adding a QTtext track to a QuickTime movie will display at very different sizes depending not just on the settings of the user's computer, but of the author's as well. It is very important for a developer adding captions to media to be aware of a variety of issues and solutions, and it is also very important for individuals or groups to function as liaison between rich media developers and producers of the major media players, to ensure that issues can be remedied.
Access for People who are Blind or Visually Impaired
Currently, the most common solution to providing access to rich media for people who are blind or visually impaired is to provide either audio descriptions or an asynchronous text alternative. It is common practice for open descriptions to be added to the existing audio track and the new audio to be combined with the video. All users hear open descriptions, which is not necessarily desirable or practical. However, SMIL gives developers the ability to offer closed descriptions that are audible only when a user elects to hear them. To do so, users need only to modify their playerÕs preferences. This solution allows the developer to produce one version of a multimedia presentation that works for everyone.
With the release of the newest versions of Macromedia Flash and Macromedia Authorware it is possible to make rich media accessible to screen readers. Along with this new potential comes a host of issues for developers to grapple with. User agents that support Flash content do so in slightly different way, creating confusion and frustration for Flash developers. Currently, Flash and Authorware are the only media types that can easily be developed to deliver information to screen reader users.
With the release of SMIL 2.0 from the W3C, developers now are able to create audio descriptions that are "extended", meaning that the video and program audio are paused to allow an audio description to be inserted in a space where there would normally be insufficient time. As with captions, there are a variety of examples available on the Rich Media Accessibility Web site that demonstrate extended audio descriptions.
Much progress has been made in the past few years. The Section 508 regulations have increased the amount of amount of captioned and described rich media available, and since the release of SMIL 2.0 as a W3C recommendation modifications to SMIL players have been made and now await content authored in SMIL 2.0. Even with legislation and a higher level of tool availability for making accessible media, accessible media will not become the norm until developers understand how to make media that is accessible. Online resources such as the Rich Media Accessibility web site and a greater availability of training resources that highlight strategies for creating accessible media will help ensure that developers have the information necessary to create content that everyone can use.
(1) W3C's Web Content Accessibility Guidelines http://www.w3.org/TR/WCAG10/
(2) Section 508 Regulations http://www.section508.gov/final_text.html
Access to Rich Media project site: http://ncam.wgbh.org/webaccess/arm
CPB/WGBH National Center for Accessible Media: http://ncam.wgbh.org
Rich Media Accessibility Web site: http://ncam.wgbh.org/richmedia
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