Flash and Accessibility (2003)
As the Web has evolved, new software and applications have been developed for use on Websites. Many of these new applications are proprietary products that don’t use standard features recognised by the World Wide Web Consortium (W3C). The use of non-standard formats can cause significant accessibility problems for some people.
“Use W3C technologies (according to specification) and follow accessibility guidelines. Where it is not possible to use a W3C technology, or doing so results in material that does not transform gracefully, provide an alternative version of the content that is accessible.
Many non-W3C formats (e.g., PDF, Shockwave, etc) require viewing with either plug-ins or stand-alone applications. Often, these formats cannot be viewed or navigated with standard user agents (including assistive technologies).”
Web Content Accessibility Guideline 11.
This Accessibility Guideline is probably one of the most contentious and difficult to interpret. In many cases the potential accessibility of a non-W3C application that requires specialist software is determined by three factors:
- The inherent accessibility of the application, or application version.
- The availability of user software (readers) to render the application, and the technological capacity needed for that software.
- The ability of current assistive technologies to access content generated by the application and rendered by the user software.
Macromedia Flash is a widely used tool for creating multimedia elements. Flash can generate interactive animations that deliver considerable visual impact with relatively small sized files. Flash content is browser independent and looks the same on all graphical browsers that are equipped with the necessary Flash plug-in or reader.
Before the simultaneous release of the Flash MX authoring tool and the Flash Player 6, Flash generated content was inaccessible to many disabled Web users. It was not possible to add alternative text equivalents to the visual content for users of screen readers or caption audio content for users with impaired hearing.
Although Flash presented accessibility barriers for many people with physical disabilities, in some cases the use of Flash enhanced accessibility for people with cognitive and learning disabilities. A concept or process is sometimes considerably easier to understand when it is presented in a simple, elegant animation rather than explained in words.
The Move to Accessibility
With the release of Flash Player 6 in 2002, Macromedia provided a player that supports Microsoft Active Accessibility (MSAA) to serve as a link between appropriately made Flash material and assistive technologies. At the time of the release, only Window-Eyes (from GW Micro) supported the accessible Flash content. A short while later Freedom Scientific released a new version of JAWS, the most widely used screen-reader, which could also access Flash 6 material.
A user who has Flash Player 6 installed, and a screen reader that supports it, can theoretically navigate Flash MX generated content that is exported for Flash Player 6 in much the same way as they would an accessible HTML page. They can read text content line by line, hear descriptions of movies and images and tab from one actionable item to the next.
When they encounter a Flash movie the screen reader loads the movie and notifies the user. “With the Window-Eyes screen reader, the user hears “Loading… load done.” Once a piece of content has been read, the screen reader moves on to read other parts of the Macromedia Flash content and the rest of the page.
A unique feature of Macromedia Flash content is that it may change over time. As the content changes, Macromedia Flash Player 6 sends a signal to the screen reader notifying it that there has been a change. When the screen reader receives this notification, it automatically returns to the top of the page and begins reading it again.”
Macromedia Flash MX Animation (accessed 15 May 03)
Flash however, is not device independent as required by the Web Content Accessibility Guidelines.
“Ensure that any element that has its own interface can be operated in a device-independent manner”.
WCAG Checkpoint 9.2
For people who do not use a mouse to access the Web, Flash content captures the keyboard if the user has Flash Player 6 or lower installed, not allowing the user to tab beyond the Flash. This is a major problem for visual mouse-impaired users and for vision impaired screen-reader/keyboard users. The problem has been solved with Flash Player 7.
Making Accessible Flash
The Macromedia Flash MX authoring tool was designed to help developers create accessible Flash content. The inclusion of an accessibility panel (more later) in Flash MX allows designers to add names and descriptions to whole Flash movies and objects within movies in a similar way to ‘alt’ and ‘longdesc’ text equivalents for HTML images. Text equivalents can also be can also be assigned to buttons, however each graphic should be contained in its own movie clip and given an instances name.
Flash Player 6 automatically presents the text content of any Flash presentation, including text in basic form elements such as input fields and check boxes, to an assistive technological device that supports it.
Designers can use the accessibility tools of Flash MX to hide individual elements that present no content from screen readers. Also, according to Macromedia:
“In the example of a rotating banner ad, a single text equivalent for the entire ad would convey the content of the advertisement to the user and prevent the screen reader from constantly returning to the top of the page.”
Macromedia Flash MX Animation (accessed 15 May 03)
The same Macromedia accessibility page also offers the following warning.
“Designers and developers should refrain from using animated movie clips or other animation within button symbols in Macromedia Flash MX. The use of such animations makes it difficult for screen readers and other assistive technologies to work with buttons.”
Most Flash movies are embedded with two tags; <object>, which is primarily needed by MS Internet Explorer; and <embed> which is used by Netscape and similar browsers to display Flash movies. This practice can cause some compliance problems, primarily because <embed> is non-standard, and can reduce accessibility. Drew McLellan discusses this issue and a possible solution in the A List Apart article “Flash Satay“.
Providing text equivalents for images will be of little value if a vision impaired user who is relying on a screen reader is unable to hear what is being read. If a site contains background music or sounds it is desirable to include an option for muting that sound so that screen reader users are able to hear the text equivalents to the Flash content.
The W3C Web Content Accessibility Guidelines recommend colour alone should not be used to communicate information since people who can’t differentiate between colours may not be able to access that information. Developers of Flash material should remain mindful of this guideline, particularly when it comes to choosing text and link colours. They should also avoid using colours and colour names as action keys, for example “select the red text for the next page”.
Using the Accessibility Panel
A central new feature of Flash MX is the addition of an accessibility panel that enables designers to control the accessibility of a Flash movie and some elements of a movie. The accessibility of graphics can also be enhanced, but only after they are converted into movie clips.
To address the accessibility of a whole movie, rather than the individual elements it may contain, select only the movie. Selecting the different elements in a Flash movie will activate an accessibility panel with the relevant options for that selection.
Make Movie Accessible:
This option is selected by default and can be used to provide a text equivalent name and clear description for a movie. Names and descriptions should also be provided for different elements within a movie as they are created.
Deselecting this option will hide a Flash movie that provides no content from assistive technologies.
Make Child Objects Accessible:
Also selected by default, this feature allows objects (elements) within a movie such as buttons to be more accessible. Screen readers will identify the different objects by speaking their names as they are encountered.
By deselecting this option, child objects can be hidden. In the case of text animation this will also prevent screen readers from reading the animation text.
When this option is selected Flash will automatically generate a name based on what it can determine about the object from text equivalents and text labels as well as the surrounding content.
Input field for a short text-equivalent name for a movie or object, similar to alt text. The name should be meaningful and short, less than 256 characters.
Input for additional descriptive information, similar to longdesc. The description should include an indication of the purpose of an object and any action that may result if that object is selected.
Can be used to provide a keyboard shortcut to a particular object.
Video Captions and Subtitles
“Flash can be captioned and subtitled, and now that Flash authors can incorporate video into Flash, this is more important than ever. Since caption and subtitle text will change often, it needs to be hidden from screen readers to avoid repetitive voicing of ‘Loading page, load done’.”
Flash MX: Moving Toward Accessible Rich Media (accessed 22 May 03)
This ‘A List Apart’ article by Andrew Kirkpatrick briefly outlines four ways of including captions and subtitles within a Flash video.
Andrew Kirkpatrick coordinates the CPB/WGBH National Center for Accessible Media (NCAM) in Boston. NCAM has developed MAGpie (Media Access Generator), a free multimedia tool for generating captions and audio descriptions in XML files. Flash parses a caption XML file to display the caption data stored in it. MAGpie can also be used to prepare audio description files for a Flash presentation.
MAGpie is available at: http://ncam.wgbh.org/webaccess/magpie/
With the release of Flash MX and Flash Player 6, Macromedia demonstrated a clear ongoing commitment to accessibility that has been widely acknowledged and praised by many people working in the area of disability support. A number of significant issues however, remain unresolved.
For example, some web users are unable to use a mouse and rely on the keyboard or alternative input devices. Many non-mouse interactions with a web page mirror the actions of the tab key and, with a conventional HTML page, the tabbing order can be set. Flash 6 determines the tab order and when this is not optimal it can make tabbing around a Flash page very difficult. Flash also doesn’t enable keyboard access to forms.
Accessibility advocate and author, Joe Clark, outlines some other problems in his ‘A List Apart’ article, “Flash MX: Clarifying the Concept.” (accessed May 2003)
Finally, the key question for website administrators and developers. Is the current version of Flash sufficiently accessible to meet the W3C Web Content Accessibility Guidelines and the demands of the Australian Disability Discrimination Act?
“The provision of information and online services through the Worldwide Web is a service covered by the DDA. Equal access for people with a disability in this area is required by the DDA where it can reasonably be provided.”
World Wide Web Access: Disability Discrimination Act Advisory Notes. Australian Human Rights and Equal Opportunity Commission (HREOC)
The answer to this question is a judgment call. It will need to be made on a case-by-case basis, depending on what the Flash material is being used for and the needs of the user. Some websites use Flash primarily for eye-catching or decorative purposes, for example a flower that blooms or a rotating corporate logo. These decorative elements often do not convey essential information, or at least information that is likely to be pertinent to people with disabilities. In these cases the level of accessibility support now available with Flash MX and Flash Player 6 and 7 is probably sufficient.
On the other hand, some websites use Flash to present navigational elements or to communicate key site content. In these cases, the accessibility limitations of Flash, and just as importantly, the lack of wide spread support for Flash Players by assistive technologies, may cause significant problems for some users. Alternative access to the information contained in the Flash element should be provided, ideally in the form of a standard HTML version of the content.
References and Additional Information
- Maximum Accessibility: Making Your Web Site More Usable for Everyone. John Slatin and Sharron Rush, 2003. Addison-Wesley, Boston.
- ActionScript: The Definitive Guide 2nd Edition. Colin Moock, 2002, O’Reilly.
- Flash MX: Moving Toward Accessible Rich Media. Andrew Kirkpatrick. A List Apart website.
- Flash Satay. Drew McLellan. A List Apart article.
- Macromedia Flash MX Animation
- Macromedia Flash FAQ
- Macromedia Flash Support Center Action Script Dictionary
- Flash Access: Unclear on the Concept. Joe Clark. A List Apart
- Flash MX: Clarifying the Concept. Joe Clark. A List Apart
- Flash News Flash: It’s Accessible. Lisa Delgado. Wired News website.
- Use of Flash on HP.com
- Flash MX Accessibility Issues. Jason Perry. O’Reilly Network
- Accessible Electronic Content: Macromedia Flash
- Flash Usability Whitepaper
- Making Flash Usable for Users With Disabilities. Jakob Nielsen, Alertbox article.