Making CD-ROM's Multimedia Work for All Users
Computer in Libraries
By Tom Wlodkowski
June, 1999
Advances in computer technology have brought most people as close as a mouse click to a wealth of information. It is no longer necessary to flip through volumes upon volumes of an encyclopedia to access a map of Africa, or to search for information about Babe Ruth. Today, we can simply show up at our local library, ask for our favorite encyclopedia on CD-ROM, and sit down at a nearby workstation and start clicking. While multimedia encyclopedias have revolutionized how people with disabilities access information, especially individuals who are blind or mobility impaired, they and other multimedia products also present some pitfalls. Fortunately there are readily available solutions that, if incorporated into multimedia software during the design phase, will make it universally accessible. But if full access is to be achieved, product developers need to be made aware of these pitfalls and how to eliminate them, and purchasers of software need to know what to look for and ask for before making a purchase.
How, for example, can a deaf person access the abundance of audio contained in these products? How can a blind person search for an article when the search controls are contained in an image, or learn from the array of video clips (an added bonus to the multimedia encyclopedia) if the visual images are not described? How can an individual with a physical disability operate the software with a single-switch device if product developers rely on one's ability to use a mouse in order to navigate? This article will answer some of these questions, profile work underway at the CPB/WGBH National Center for Accessible Media (NCAM) to improve multimedia accessibility, and conclude with a set of recommended guidelines to follow when purchasing multimedia software.
NCAM's primary mission is to research, develop and test methods of integrating access to meet the needs of people with sensory disabilities -- individuals who are blind or visually impaired, or deaf or hard-of-hearing. Access techniques include closed-captioning and audio description (the insertion of narrated descriptions of key visual elements into the natural pauses in dialogue of a video clip). Most of the solutions mentioned in this article will address the needs of individuals with sensory disabilities. However, if steps are taken to improve navigation for blind users by implementing an effective keyboard interface, many barriers confronting individuals with physical disabilities will be overcome as well.
Barriers confronting blind users
The largest number of access barriers common to multimedia software effect blind or visually impaired users. The barriers fall into two categories; (1) the ability to navigate around the product, and (2) the ability to access visual content. Since there is a high degree of customization in the design of multimedia software, and prevalent use of graphics to invoke navigation and to display text, access technologies cannot effectively interact with these products. The access technologies used by blind and visually impaired people to interact with mainstream computer applications are known as screen readers and screen magnifiers. A screen reader is software that conveys what's on the screen to the blind computer user via speech or braille output, and allows the user to use a conventional keyboard in place of the mouse to navigate to and operate all application controls. Since screen readers work best with text and standard operating system graphics (Windows dialogue boxes and buttons for example), today's highly graphical and nonstandard design of multimedia products make them virtually impossible to use by blind people. A screen magnifier provides the ability to dramatically enlarge the entire screen or portions of the screen so that a low vision user can more easily view the display and use the mouse to navigate. Often times the magnifier user is not able to enlarge the video components of a multimedia product, and may experience difficulty navigating a screen that contains animating images, a nonstandard cursor, etc.
Ongoing research
To address these issues, the National Science Foundation's Programs for Persons with Disabilities funded the CPB/WGBH National Center for Accessible Media (NCAM) to create and disseminate guidelines. These guidelines will enable educational software developers to create products for the classroom that are as user-friendly and educationally enriching for blind students as this software has become for sighted students. While the CD-ROM Access Project is addressing issues specific to the usability of science and math based multimedia by blind students, many of the guidelines will apply to a broader range of multimedia software, including encyclopedias. The project is focusing on development platforms such as Java, and exploring how developers can incorporate features that improve usability using popular authoring tools like Macromedia Director. NCAM is also developing tools and working with standards organizations to ensure that audio description and closed-captions can be included in digital multimedia. Our work in conjunction with ongoing efforts at Microsoft has resulted in Microsoft Encarta Encyclopedia becoming the first-ever commercially available multimedia product to include closed-captioning.
Solutions
There are several readily available solutions that have the capability to significantly improve access to multimedia software for consumers with disabilities. These include:
Java
Java is a powerful programming environment that offers software developers the ability to design one program that can run on multiple computer platforms (Windows and Macintosh for example). It also offers developers the ability to implement features essential for providing access to users with disabilities (effective implementation of a keyboard interface, the ability for a blind user to obtain audio output of the on-screen display, etc.). Work by the access division of Sun Microsystems, developers of Java, and by IBM's Special Needs division have made the Java environment truly accessible. The tools they have created eliminate the need for cumbersome retrofitting and will provide streamlined access to future software.
Microsoft Active Accessibility (MSAA)
Using MSAA, an applications programming interface developed by the Microsoft access group, software developers can use entirely graphical custom interfaces while still making each element known to a screen reader. In other words, a developer's choice to place a non-standard looking button on the screen will not prevent a screen reader from recognizing the button provided the developer implements MSAA in their design. In order for MSAA to be effective, it is important that any computer workstations in your library designated for use by blind or visually impaired patrons are equipped with an MSAA capable screen reader. MSAA is exclusively a solution for Windows based products.
SMIL
Synchronized Media Integration Language (SMIL) is a multimedia format that allows authors to attach closed-captions and audio descriptions to audio or video components. One common tool for playing SMIL presentations is the RealPlayer G2 from RealNetworks. SMIL was developed by the World Wide Web Consortium, an international industry consortium that publishes standards for the Web. SMIL formatted multimedia can also be delivered locally on a CD-ROM.
SAMI
Synchronized Accessible Media Interchange (SAMI) is a Microsoft-authored public specification that allows closed-captions and audio description to be played in the Windows Media Player. SAMI is the technology used to create the closed-captions in Encarta Encyclopedia.
Software purchasing guidelines
While the solutions mentioned above hold great promise for the short and long term future of improved access to multimedia, there are several guidelines you may wish to follow to ensure your library is home to the most accessible software available. The more that software publishers hear about the need for universally accessible software, the more likely they will be to address the needs of all users. You may also wish to incorporate this information into your purchasing process.
Here's what to look for:
- Does the program use standard menus? Can your access technology track the cursor as you use these menu?
- Does the program provide keyboard commands for important features?
- Are there preferences, options, or settings that make the product easier to use with assistive technology?
- Is all essential text on the screen read by your screen reader or smoothly enlarged by your screen magnifier? Can the text size be made larger in the product preferences?
- Are interactive activities usable with a keyboard? Or, for magnifier users, are icons and objects clear enough and screen layout simple enough that mouse navigation is possible with the magnification level the user requires?
- Do photos or other visual elements enlarge well?
- If essential information is conveyed in audio, is it also available visually, for example as captions, visual alerts, or written instructions?
- Is the product's help accessible? Does it give information about how to use the product in language appropriate for the user?
- Does the user have sufficient mastery of the assistive technology to use it with this software? Or does this software require skills that will take more time to acquire?
NCAM is based at WGBH-TV, the public broadcaster in Boston. WGBH has a long history of ensuring that media is accessible to all users. In 1971, WGBH pioneered closed-captioning for deaf and hard-of-hearing individuals. In 1990, the station launched Descriptive Video Service (DVS) to meet the need of blind and visually impaired viewers. The onset of the world wide web and the increase in popularity of CD-ROM technology opened entirely new venues for closed-captioning and DVS description. If 'GBH's core access technologies were to be effectively delivered in these media, many issues such as the ability of a blind person to navigate around a highly graphical menu screen had to be addressed. As a result, NCAM began work on research and development projects in 1993. For more information on the CD-ROM Access Project and other NCAM projects, visit the NCAM Web site at or contact the author at 617.300.3486.
