Go to previous article
Go to next article
Return to 2002 Table of Contents
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.
The Access to Rich Media project is striving 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.
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.
The National Council on Disability's "Report on Access to Multimedia Technology By People with Disabilities"(1) asserted in 1998 that the current state of multimedia access for people who are blind was bleak. This assessment has not improved significantly as rich media technologies have become more widespread. The potential of these technologies to improve the lives of people with sensory disabilities is great, as countless business, news, information, shopping, education and cultural Web sites already include rich media. While strategies exist for providing access, little of this material is currently accessible to viewers with sensory disabilities.
Parents, students and teachers with sensory disabilities are visiting library, museum, and education sites only to find inaccessible audio, video, and animations. Science-focused blind or deaf students are finding university Web courses full of inaccessible media, graphs, mathematical equations and symbolic notations. Blind or deaf patients and caregivers cannot benefit from Web-based health support services, which use animation, video and/or audio-based illustrations and instructions. Blind or deaf scientists, researchers and managers are discovering that lack of access to Web-delivered media could greatly impact their professional lives. Employees from every industry can expect technical training, professional development and corporate information to incorporate rich media delivered via Web sites, LANs and intranets. Lotus, Oracle, Microsoft, IBM and many other technology developers offer groupware and knowledge management software packages, which utilize time-based media and real-time collaboration tools in business applications.
According to the results of a study released in June, 2001 by Kinetic strategies, 119,000 North Americans are signing up for high-speed Internet access to their homes per week(2). As broadband access to the Internet increases, the amount of rich media will undoubtedly follow. This proliferation of rich media and dynamic Web pages will create serious and pervasive barriers for people with sensory disabilities in almost every Web-based application imaginable.
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.
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. Other players, including Macromedia's Flash player and BMW's movie player, lack this functionality.
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.). Also at the site is an example of how caption data can be used to help search and locate specific areas in a video.
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.
Currently, the 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 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.
The most complicated issue with audio descriptions is in the delivery. This does not need to be a significant problem, as clear methods exist for providing described versions of audio and video files. Developers need to be made aware of what is required, and to employ strategies that address the needs of the users. For example, a developer might offer three versions of a video: one with the video and plain (undescribed) program audio; one with video and described program audio; and one with described program audio but without video. By downloading only the described program audio the blind user can save bandwidth, but the version with both video and described program audio is available for visually impaired users, if desired.
As rich media offerings become more prevalent, some sites will offer information in rich media that was previously provided in HTML. At present, screen-reader support for rich media players is lacking. The SMIL 2.0 specification provides ways for developers to include additional information in a rich media offering, but more work is needed to make sure that players and screen readers can work together. Providing screen-reader access to Flash content is in progress, but more work needs to be done for SMIL.
Much progress has been made in the past few years. Certainly the Section 508 regulations will increase the amount of amount of captioned and described rich media available, and the release of SMIL 2.0 as a W3C recommendation and the ensuing modifications to SMIL players will have an impact on the ways rich media is developed. There are significant issues to address -- advocating for the production of accessible rich media, correcting player and platform incompatibilities, and providing screen-reader access to complex rich media presentations. Better solutions for a variety of media types are needed -- in order to make sure that any efforts are ultimately going to be successful, representatives of the disabled communities must be involved.
(1) ACCESS TO MULTIMEDIA TECHNOLOGY BY PEOPLE WITH SENSORY DISABILITIESNational Council on DisabilityMarch 13, 1998http://www.ncd.gov/newsroom/publications/sensory.html
(2) Broadband hits 9 million-home markErich LueningZDNet News June 1, 2001 http://www5.zdnet.com/zdnn/stories/news/0,4586,5092009,00.html
(3) W3C's Web Content Accessibility Guidelineshttp://www.w3.org/TR/WCAG10/
(4) Section 508 Regulationshttp://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
Go to previous article
Go to next article
Return to 2002 Table of Contents
Return to Table of Proceedings