Skills for Access

Why this is important

Providing text-equivalents enables media that contains spoken or other audio information important to understanding the media's content (for example on-or off-screen sound effects, or background music) to be accessible to anyone who has difficulty hearing, or is unable to hear, the media soundtrack. Any Flash resource with spoken or non-spoken audio important to its understanding may cause problems unless the audio information is provided in another way.

General Principles

The flexibility of Flash as a multimedia technology offers several options for providing alternatives to audio content. Sound alerts could be replicated by visual cues, such as obvious changes to the appearance of the resource, while spoken information provided as a soundtrack that plays could be replicated by the provision of on-screen text.

For more complex Flash content, it's also possible to provide captions either by creating them as part of the movie, or using a specific tool to generate and combine a separate caption file within the Flash player, or by playing the Flash movie in an alternative media player and providing a synchronised caption file to play alongside the Flash movie.

NB: We have provided general advice on captioning in a separate How To: Provide text equivalents for audio - general advice on captions.

Before you continue

The advice on this page helps you avoid introducing a specific accessibility barrier, but it's not a magic formula. To avoid attempting to follow a technical solution that is not appropriate to the resource and its intended purpose, you need to know the context in which the multimedia resource is being used:

1. The purpose or aim of the multimedia resource in question, and whether it is being used to supplement another resource in the learning environment, or whether its use is required by students.
2. The target audience, their knowledge and expectations, and the type of browsing and assistive technology that they may be using.
3. Whether the information and experiences provided by the multimedia technology are already available in an equivalent, alternative form.

For more background on this approach, see our Guide to the use of multimedia in accessible e-learning.

Technique Details

The exact steps required to ensure that audio information in your Flash movie has an appropriate textual equivalent depend on the nature of the movie and the audio information. Consider the following questions:

• Would your movie be best served by providing captions?
• Is the nature of the audio content more suited to other visual or textual equivalents?
• If the source of the audio is an imported video clip, could it be captioned before being incorporated into the Flash movie?

It may be that the audio information is in fact a narration of information provided in text and graphics, and in such a case there would be no need to caption what is effectively an alternative to the movie's visual information. Example 1 is a Flash animation where text has been provided as part of the resource design, along with spoken information.

Example 1: Play the Flash movie.

Where captioning is the best strategy, four alternatives exist.

Option 1: Use software to create captions for Flash. These solutions provide captions in an XML file which can then be processed by the Flash Player. Within this XML file is timestamp information plus caption text (in multiple language captions if required) and style information. Examples include:

• HiCaption, from HiSoftware. An extension for Flash MX and MX 2004, this allows authoring and integration of captions for Flash movies. As of March 2005, the cost of this solution was US$99.
• MAGpie, the free captioning software for web based video and audio, also has a facility to author captions for Flash movies.

Option 2: Use Synchronised Multimedia Integration Language (SMIL) to combine a caption file with the Flash movie in a media player that supports both Flash and SMIL. For example, WebSavvy demonstrate a way in which Real Player can play a captioned Flash movie, by using SMIL to combine a Real text caption file with a Flash movie. QuickTime Player can also play .swf Flash movies.

Option 3: Provide the caption text as part of the Flash movie's timeline itself - you then have full control over positioning, styling and timing of the appearance of the caption text. However, even Macromedia admits that this process of providing captions is likely to be tedious in the extreme for all but the shortest of movies.

Option 4: If part of the movie's audio content is an embedded video clip, the video can be pre-captioned before being included in the Flash movie. A disadvantage here is that there is a loss of flexibility in terms of being able to turn on and off the captions when viewing the movie. Resources specifically aimed at describing best methods of providing captions (or preserving existing captions) for the embedded video seem conspicuous by their absence. We look forward to updating this paragraph when more information emerges!

Testing

The basic objective of testing is to answer the question "Does the Flash resource still make sense when sound is not available?" You can test how effective your solution is just by turning off your speakers! Make sure also that the task of turning on and off captions - or at least choosing between captioned and non-captioned versions of the Flash movie - is also easy to perform.

It would also, of course, be beneficial obtaining feedback from end users, particularly people who are deaf or hard of hearing. Remember that they are likely to be unfamiliar with the resource so will not be able to judge whether the text-alternatives you provide are a true reflection of the audio content of the Flash resource.