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Accessible Flash

By Nicola McIlroy, published 29th June 2004.


Over the years, Flash content has been widely criticized for contributing to accessibility and usability problems on the Internet. In the US, the implications of the legislation contained in Section 508 of the Rehabilitation Act [1] - to ensure that technology used by US federal agencies meets specific accessibility needs - have been widely seen as being a core factor in accessibility improvements made by Macromedia to Flash.


Until recently, the main problem with Flash content on the Internet was for users browsing with assistive devices, such as screen readers, as they were not able to access Flash content. Such devices were designed to create an off-screen model of the HTML text and hyperlinks in a webpage and to ignore graphics. A published flash movie is a graphic, usually referenced from an <object> or <embed> tag in HTML, and was too deeply embedded in the page to be accessed by such a device.


Flash content often requires mouse-clicks for navigation and users relying on the keyboard alone, were unable to navigate Flash content, unless this had been specifically programmed by the Flash developer. Flash content once accessed within a page, maintained focus, meaning that the user had no way to exit from Flash content using the keyboard alone. Other accessibility problems relating to Flash content included:


With the release of Flash MX in 2002 and Flash Player 6+, Macromedia significantly improved the accessibility of Flash, particularly for blind people browsing the Internet using screen readers.


The main improvement to accessibility in Flash MX was added support for Microsoft Active Accessibility (MSAA). MSAA is an Application Program Interface (API), which has allowed users of assistive technologies to automatically access the contents of a Flash movie by sending messages to a screen reader. As a result, screen readers supporting MSAA can now access text elements, buttons, input text fields, movie clips and entire Flash movies automatically. [3]


This is a big advancement - the main caveat is that only up-to-date versions of JAWS and Windows Eyes screen readers, using Flash Player6+, can provide even marginal access to Flash content. Using MSAA has introduced important accessibility barriers of its own; Flash is not inherently accessible and being a Microsoft Technology, it is unlikely it will ever be available on any platform except Windows. [4]


Macromedia have also added an 'Accessibility Panel' to Flash MX. This panel offers a number of accessibility features to the Flash developer, such as Flash elements to be hidden or revealed to screen readers. This improves accessibility by allowing the developer to hide continually animating elements which do not convey content, and cause problems for assistive devices by continually refreshing them. [5]


Flash MX also allows the developer to add a text equivalent for a single element, a group of elements, or an entire movie, through the 'Accessibility Panel'. This alternative text can be automatically accessed by screen readers using MSAA, and is Flash's equivalent of the HTML <alt> and <longdesc> attribute.


Other accessibility features are now possible with Flash MX:


Although there are limitations, Macromedia have improved the accessibility of Flash MX, and continue to do so with the release of Flash MX 2004. This version of Flash offers new accessibility features such as a powerful captioning tool from HiSoftware and a collection of validation and repair tools for accessible authoring. [7, 8, 9]


There is no doubt that Macromedia have worked very hard to improve the accessibility of Flash, through the addition of a number of features to new releases of the technology, and their efforts should be recognised. Indeed, Jakob Nielsen has reformed his opinion of Flash from being a 'usability disease' [2] to 'an opportunity' [10] for advanced Internet features to be made available to disabled people. While others, such as Joe Clark, who had felt that Macromedia were 'unclear on the concept' [11] of accessibility, now feel that Macromedia are aware of what needs to be done and have taken serious steps to improve the accessibility of Flash. [12] There are still improvements to be made though, and even then many people with older assistive technologies may still find Flash inaccessible.


What we mustn't lose sight of, though, is the ability of Flash in its own right as an assistive technology - through creative use of animation and multimedia, it can make textual information much more accessible to many people, not least to people with various cognitive impairments, including learning difficulties. As always, Flash works best when it is used as an enhancement to textual content.


Accessibility Tips for Flash Designers


Examples of Accessible Flash


References

  1. http://www.section508.gov/index.cfm?FuseAction=Content&ID=12 - Section 508
  2. http://www.useit.com/alertbox/20001029.html - Jakob Nielsen critique of Flash
  3. http://www.macromedia.com/macromedia/accessibility/features/flash/ - Macromedia's Site
  4. http://www.webaim.org/techniques/flash/ - MSAA accessibility barriers
  5. http://ncam.wgbh.org/richmedia/tutorials/refresh.html
  6. http://www.netreturn.com.au/common/flash100_03.html
  7. http://www.macromedia.com/macromedia/accessibility/features/flash/author.html - Accessibility and Macromedia Flash MX 2004
  8. http://www.hisoftware.com/accrepair_flash/AccRepair-FlashTutorial.htm - AccRepair®
  9. http://www.hisoftware.com/hmccflash/index.html - Hi-Caption SE
  10. http://www.useit.com/alertbox/20021014.html - Jakob Nielsen on accessibility of Flash
  11. http://www.alistapart.com/articles/unclear/ - Joe Clark's critique of Flash MX accessibility
  12. http://old.alistapart.com/stories/flash_mx_clarifying/ - Joe Clark 'Clarifying the Concept'