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E-Training 2 - Accessible Multimedia

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Multimedia elements are some of the most commonly encountered challenges of Web-based training programs for users with disabilities. Audio and video add flair and personality while also providing valuable content information. However, the barriers to access that multimedia elements can create are as numerous as the types of disabilities your potential trainees may possess. This complicates the development process, because all multimedia components must be made fully accessible to a wide range of disabilities.

Luckily, a few accommodations will prevent the majority of accessibility barriers from ever becoming an issue. One of the simplest ways of making video accessible is the use of captioning. Captioning refers to written description of actions and words during a video presentation. This allows users who have hearing disabilities to access the information being presented aurally. Captions can also serve a dual function by making it very easy to create written transcripts of the presentation, which users with visual disabilities can then access via screen reader.

Captioning can be a time consuming process, but is necessary in order to provide a fully accessible training experience. A number of software applications can make it easier for trainers to provide captioning service to their students. The Media Access Generator, also known as MAGpie, is one such tool developed by the National Center for Accessible Media. MAGpie is available free of charge, and can get content developers up and running making their own captions in a matter of minutes. In a later entry we’ll present readers with a short MAGpie tutorial that explains all of the major functions and provides some tips for navigating the interface.

Captioning can take two forms, both of which can be useful. Closed-captions are turned on and off by the user through a control system, much like on a television. Open-captions are actually embedded into the video stream, and are always displayed. Typically, closed-captions are preferred, as these are accessible to screen reader software while open-captions are considered part of the video image, and therefore unable to be converted. Most captioning software will produce closed-captions, and many will allow text files to be imported that make the conversion process simple.

When captioning multimedia, content creators must pay attention to more than just the words in the captions. Appropriate color and contrast are just as important as the caption text itself. Many color combinations can make it difficult to read the screen at a normal viewing distance, and virtually impossible for viewers with color blindness or other visual disabilities. Many captions use white as a preferred color; however, they sometimes become impossible to read depending on the background color.

In a study by the National Center for Accessible Media (NCAM), it was found that next to white, yellow and blue were the two most acceptable colors for captions. If using a predominantly white background, then choose a different caption color or provide a contrasting background for the captions.

Transcripts are another consideration when presenting multimedia. Unfortunately, current technology solutions for producing transcripts leave a lot to be desired. Right now, the best way to create an accurate transcript is to do it by had with a text editor. Content developers can kill two birds with one stone by using the captions as a basis for the transcript, using the export feature of captioning software to create a text transcript that can be provided alongside the video.

Next time, we’ll look at MAGpie, and how exactly to use captioning software to develop accessible videos.