Planning for Accessible Video and DVD Mark Harniss Center for Technology and Disability Studies University of Washington
Dec 19, 2015
Planning for Accessible Video and DVD
Mark HarnissCenter for Technology and Disability StudiesUniversity of Washington
Why Accessible Video?
10 million individuals in the United States who are blind or visually impaired. 1.3 million are legally blind.
10 million individuals in the United States are hard of hearing and approximately 1 million are functionally deaf.
Increasingly video is being used to convey critical information on the web and in classrooms.
Why Accessible Video?
Federal and state laws may require accessible video.
Developing accessible video does not just benefit users with disabilities, but other users as well.
Once a video is created it is difficult and expensive to go back and retrofit it to include accessibility options. It is always better to plan for all foreseeable uses
and to prepare for all foreseeable audiences.
What are the features of an accessible DVD?
CaptionedAudio describedIf a menu driven DVD, then voiced
menus
Captions
Captioning involves synchronizing text with the audio content of a video. There are two types of captions (open and closed) and a third way for providing synchronized text in DVDs called subtitling.
Closed Captions
Closed captions are stored in Line 21 of the vertical blanking interval (VBI) between the frames of a television signal.
They require a decoder to display and can be turned on or off by the viewer.
Closed Captions
All televisions larger than thirteen inches that were manufactured after 1993 in the United States are required to include a caption decoder.
Closed captions will generally show up onscreen as white letters in a black box and should (must) depict all sound on the video not just speech (for example, music or children crying).
Open Captions
Open captions are embedded in the video signal and are always on.
Subtitles
The term subtitling is more confusing. The term is sometimes used to refer to foreign language subtitles on film, which are essentially open captions.
However, DVDs provide another way of providing synchronized text called subtitles.
Some people make the distinction that subtitles only display spoken words, not sounds.
Audio Description
Audio description (AD), also referred to as descriptive video service (DVS), provides accessibility to individuals who are blind or have low vision by describing the people and actions displayed visually on the screen.
Audio description must fit in between existing audio and follow on-screen action in a reasonable fashion.
Audio Description
It must also attempt to describe all relevant visual features while not impacting the flow of the video.
Describing scenes is a bit of an art and requires careful wording and high quality, professional narration.
Voiced DVD Menus
DVD menus are generally not accessible to screen readers and must be voiced.
Voicing require scripting, recording and programming.
Accessible DVD Demo
Accessibility and Video Development
Often producers perceive that accessibility issues are merely technical and can be addressed in post-production after shooting has been completed.
Actually, creating an accessible DVD requires that a producer juggle a complex set of factors that require decisions during all phases of video development. Defining work flow is critical
Creative Tension
Does accessibility drive design or vice versa?Captions can block important information for
individuals who are sighted.Presenting adequate audio description can
take longer than the space required in a tightly edited, fast-paced video
Ideal to achieve one versionDo we optimize for one audience or create two
versions?
Phases of Video Development
Design, Pre-production, Production, and Post-production
Design
The design stage involves planning the content and treatment, and scriptwriting.
Accessibility Decisions at Design
Set up systems for capturing captioning content If non-scripted, plan for transcripts If scripted, consider including all relevant
sounds in script
Pre-production
The pre-production stage includes everything involved in getting ready to shoot video budgeting, selecting talent, arranging
locations, and creating storyboards.
Accessibility Decisions at Pre-Production
Storyboarding Include initial draft of audio description
Although audio description should never interfere with the creative intent of a video, it may be worthwhile to consider where the descriptions will need to go in a video
This allows you to plan for shooting and editing the video.
Accessibility Decisions at Pre-Production
Storyboarding Include placement of captions
Where will they go, what will they cover?
Accessibility Decisions at Pre-Production
Pick a captioning and audio description serviceGet samples of previous work.
Accessibility Decisions at Pre-Production
Plan for DVD menu programming and voicingWhat DVD options will be built into the
menu?For example, a DVD might allow a user to
choose video only, video with captions, or video with audio description and captions.
Script and flowchart voice menus
Accessibility Decisions at Pre-Production
Budget for additional costs related to accessibility features
Production
The production stage involves all the details involved with actually shooting video shooting scenes, recording music and other
audio, and developing graphics and animations.
Accessibility Decisions at Production
ShootingConsider shooting wider to allow for
captioning---more at bottom
Accessibility Decisions at Production
Shooting If introducing individuals with onscreen text,
allow space to ID (with video description)Either shoot subject cover shot (at least :20) or
plan to intro each person with a graphic image (can be as long as needed)
Post-production
The post-production stage involves taking the raw video and transitioning it to edited video includes logging and choosing shots, editing
video, and programming the DVD
Accessibility Decisions at Post-production
LoggingChoose shots that allow for captions and
audio descriptionLong enough, enough space
Decisions at Post-production
EditingEditing is often is where decisions about
flow are madeTight editing and quick action can make it
very difficult to insert audio description in the appropriate place.
Consider opening up spaces
Accessibility Decisions at Post-production
Make captioning decisionsWhat type of captions?Where placed on screen?How deal with onscreen titles?
Modify shot or move caption?
Accessibility Decisions at Post-production
Review processWho will review adequacy of accessibility
features?Consumers?
When?Who will revise and correct?
Conclusion
Many of the decisions to be made when developing an accessible DVD or video cannot be made at post-production, but must be addressed early on in the creation of the video in order to avoid unnecessary expense later in the project.
Resources
Robson, G. D. (2004) Closed captioning handbook. Burlington, MA: Focal Press
Creating Audio Descriptions for Rich Media http://ncam.wgbh.org/richmedia/tutorials/
audiodesc.html Audio Description
http://ncam.wgbh.org/richmedia/strategies/AD.php WGBH Captioning FAQ
http://main.wgbh.org/wgbh/pages/mag/services/captioning/faq/sugg-styles-conv-faq.html