Although people with vision impairment cannot see video and those who are Deaf or hearing impaired cannot hear the audio, the content can still be accessible to them if it can be interpreted by assistive technologies.
- The location and method of access for text transcripts for media content should be considered at the design phase.
- Media players must have specific controls such as pause/play and volume control to meet accessibility requirements.
- The look and feel of media player controls must meet accessibility requirements.
- If the text transcript is located on a separate page to the media content, ensure that a link to the text transcript is located either immediately before or after the media content.
- If the text transcript is on the same page as the media content, ensure that the words “End of document” or “End of transcript” are included at the end of the transcript.
- Ensure the text transcript is in HTML webpage format or a plain text file. Avoid using proprietary formats such as PDF or DOC/DOCX (Word).
Include within your visual design the following media player controls:
- Volume controls that are independent to the system volume controls.
- A pause and/or stop button.
- A button to turn on and off closed captions.
Ensure that your media player controls:
- Meet colour contrast requirements (see Colour and contrast: accessibility for designers).
- Have the keyboard focus indicator specified within the design (see Visible focus: accessibility for designers).
- Have text alternatives specified that describe the purpose of the control.
With the rapid expansion of broadband use, the proliferation of multimedia content has also increased. Although people with vision impairment cannot see video and those who are Deaf or hearing impaired cannot hear the audio, the content can still be accessible to them if it can be interpreted by assistive technologies. Presenting the content in different formats, perceivable by different senses, goes a long way to improving accessibility.
The main methods involve providing some or all of the following:
- Text transcripts of all dialogue and words spoken
- Audio descriptions of important visual details that cannot be understood from the soundtrack alone
- Text descriptions of important audio details that cannot be understood from the visuals alone
- Captions of words spoken
- Sign language track synchronised to the visual presentation
Don't assume Flash players
Although Adobe Flash has been a major player for embedding audio and video in webpages, it is facing competition from alternative players that do not require the Flash plugin. It is safe to assume Flash is available on most desktops, but less safe to assume it works on tablets and mobile devices to a reasonable degree. Developers are increasingly turning to non-Flash media players for compatibility with more devices, and to include greater controls, both for functionality as well as accessibility.
Plan for transcripts and long text
Designs with media players in them should also address where and how the text transcript will be accessed. Some text transcripts may create unduly long pages and can be visually hidden, linked to on a different page, or supplied as a download text file. Locating the transcript and considering how the transcript may synchronise with the media being played, or how it may be visually co-ordinated with closed captions or audio descriptions are all considerations for the designer. YouTube's HTML5 player has many features a designer may wish to borrow from or include in their layouts and interaction designs. YouTube has an HTML5 video project you can join to see the features and functionality available I the format for designers to take advantage of.
In addition to sensory conditions, people who use or depend on keyboards must also be accommodated when designing and defining media players. A common problem is called a keyboard trap, where a user enters an area of a webpage but cannot move out of the area using the keyboard, was once common in media players. For accessibility, keyboard traps must be eliminated and all functionality and controls need to be available to the keyboard.