Skills for Access

Why this is important

Providing audio descriptions enables media that contains visual or aural information important to understanding the media's content, to be accessible to anyone who is blind or visually impaired and unable to see the video's content. The task of creating an effective set of audio descriptions that are appropriately synchronised with a media clip can be challenging, and this task can be made significantly easier when using authoring software such as MAGpie.

General Principles

MAGpie (Media Access Generator) is a free software developed by the National Centre for Accessible Media in the US, and helps web developers add synchronised captions and audio descriptions to web video. It supports creation of audio descriptions for media to be played in QuickTime or Real Player, but currently not for Windows Media Player, given that player's lack of support for audio description.

At the time of writing (April 2005), the current version of MAGPie is version 2.01, and is available for Windows and Mac OSX.

NB: We have provided general advice on audio description in a separate How To: Provide audio descriptions for video or animated content - general advice.

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

There are a number of very useful tutorials which provide step-by-step instructions for installing MAGpie, and for creating and combining captions and audio descriptions with media files. These tutorials note that the installation process can be frustratingly difficult to complete successfully unless certain steps are taken in advance of the download and installation. We therefore recommend you follow - in the exact order given - the installation process described in one of the tutorials offered by WebAIM, NCAM or the University of Wisconsin.

1. Open MAGpie. Open the media file to be captioned; choose the type of media file you'll be adding descriptions to, and save your new project.
2. Now write, record and save as separate files your audio descriptions using MAGpie (of course, you'll also need a microphone to capture you speaking the descriptions!). Alternatively, you can import existing descriptions if you've already created them. MAGpie allows you to store a text transcription of each audio description - an important aspect of any transcript you may make available.
3. Play the media file, listen to the soundtrack, and note the time at which the next audio description should be played. Remember that this should be on the one hand as close as possible to the point at which the users needs to be provided with the audio description, but also at a time when the main soundtrack is silent.
4. Add the time-stamp and the filename of the audio description file.
5. Repeat steps 3 and 4 until all audio descriptions have been specified and time-stamped.
6. Review the audio described media regularly, to ensure that audio descriptions are audible, that volume levels are appropriate, and that descriptions complement rather than overlap the main soundtrack.
7. If you're providing audio descriptions in another language, open a new audio description track and repeat steps 3 to 6.
8. When complete, MAGpie will save the project as either a QuickTime or Real SMIL file. If you've already created captions for the subject media file, the relevant code of this SMIL file can then be pasted into the SMIL file you previously created to combine the base media file with the caption file.

MAGpie can also create and combine a single audio description file rather than multiple audio description files.

Testing

The process of creating an audio described video using MAGpie is by its nature lengthy and iterative, requiring constant reviewing of presentation and timing - as a result, though, this methodology requires you to regularly review and improve the quality of the descriptions. Once available on the web, playing the described resource in as many different platforms as possible is recommended. At the same time, it is well worth seeking feedback from blind and visually impaired people, although, of course it is assumed that they are unlikely to be familiar with the content of the described video.