Accessible Video in
Two Parts
Terrill Thompson
Techology Accessibility Specialist
University of Washington
tft@uw.edu
http://staff.washington.edu/tft
http://terrillthompson.com
Agenda
Part 1: Nuts and Bolts
• Closed captions
• Description
• Accessible media
players
Part 2: Making the Case
• Exploring enterprisewide strategies for
making video
accessible
Part 1
Approaches to Captioning
1. Let machines do it for you
2. Hire a captioning vendor
3. Recruit and manage volunteers
(crowdsourcing)
4. Do it yourself! (DIY)
Free or Cheap Captioning Tools
• MAGpie (Windows)
– http://ncam.wgbh.org/invent_build/web_multime
dia/tools-guidelines/magpie
• Subtitle Workshop (Windows)
– http://www.urusoft.net/products.php?cat=sw&la
ng=1
• Movie Captioner (Mac & Windows; not free)
– http://www.synchrimedia.com/
More Free or Cheap Captioning Tools
• CapScribe
– from U of Toronto
– also supports audio description
– http://cnice.idrc.ocad.ca/tools.php
Free Online Captioning Tools
• Amara (formerly Universal Subtitles)
– http://amara.org
• DotSub
– http://dotsub.com
• Subtitle Horse
– http://subtitle-horse.com
• CaptionTube
– http://captiontube.appspot.com
The Closed Captioning Process
• Transcribe video into caption-sized
segments
• Use a captioning tool to timestamp the
transcript
• Save to an output file that is appropriate
for your media type
Flavors of Closed Captions
• SubRip – SRT file, very simple and widely
supported
• Timed Text Markup Language (TTML) – A
W3C standard
• WebVTT – The preferred format for
HTML5
• And many more…
supports video accessibility
<video src="myvideo.mp4">
</video>
supports captions
<video controls>
<source src="myvideo.mp4" type="video/mp4">
<source src="myvideo.webm" type="video/webm">
<track kind="captions" src="mycaptions.vtt" default>
</video>
Description, a.k.a.
•
•
•
•
Audio description
Video description
Described video
Descriptive narration
What is Description?
• A separate narrative track, for people who
can’t see critical visual content
• Can be avoided by assuring that all important
information is communicated visually and
audibly
Types of Description
(in descending order by quality/cost)
1. Recorded audio, remixed into video
production
2. Recorded audio as a separate audio file,
synched with video by the media player
3. WebVTT text-based description, read by
assistive technologies during playback
DIY Text-based Description
• Use a captioning tool to compose description text and
synch it with the video
• Insert brief descriptions during periods when there is
no competing audio content
• Allow enough time for a screen reader to read the
description (your best estimate)
• Include all on-screen text
• Include succinct descriptions of any visual information
that is integral to the communication
• Export to WebVTT for (theoretical) use in HTML5 video
player
supports description too!
<video controls>
<source src="myvideo.mp4" type="video/mp4">
<source src="myvideo.webm" type="video/webm">
<track kind="captions" src="mycaptions.vtt" default>
<track kind="descriptions" src="mydesc.vtt">
</video>
Hiring Vendors
• Captioning Service Vendors
– http://www.dcmp.org/ai/10/
• Description Service Vendors
– http://www.dcmp.org/ai/179/
Source for both: Described and Captioned Media Program (DCMP)
Media Player Considerations
• Does it support closed captions?
• Are controls accessible by keyboard?
• Are controls properly labeled for screen
reader users?
• Does it support closed text-based description?
• Does it include an Application Program
Interface (API) so you can extend its
functionality (e.g., with video search or an
interactive transcript)?
Internet Explorer 10 has good support
for accessibility
Universal Media Player (UMP)
UMP Features
• Support for closed captions
• Support for closed text-based description
• Support for description via swapping to an alternative
video source
• Fully accessible player controls
• A fallback player (JW Player) that looks and behaves
exactly like the main player
• Ability to search videos using their captions
• An interactive transcript (assembled using captions and
description)
• Controllable with hot keys from anywhere on the page
• Customizable via Settings button
Video Search
Interactive Transcript
Customizable
More on DO-IT Video and UMP
• Our website:
– http://uw.edu/doit/video
• The open source Universal Media Player (UMP):
– Coming soon
– Watch http://terrillthompson.com/blog
Part 2
Agenda
Part 1: Nuts and Bolts
• Closed captions
• Description
• Accessible media
players
Part 2: Making the Case
• Exploring enterprisewide strategies for
making video
accessible
Making the case:
Who benefits from accessible video?
• People who are unable to hear the audio
• People who are unable to see the video
• People who are unable to use a mouse
• People with cognitive disabilities
Making the case:
Who else benefits from accessible video?
• People whose first language is not the
one spoken in the video
• People who don't understand the
language of the video at all
• People who have low Internet bandwidth
• People who need to search for particular
video content
• People who are busy
Video search is here
Example from MIT OpenCourseware: http://interactive.3playmedia.com/mitocw/
Video translation is here
Example is from youtube.com
Interactive transcripts are here
Captioned video supports research
Example is from http://www.aljazeera.com/indepth/interactive/
We want all videos to be captioned
Percent of a university's video accessibility barriers removed by captioning one
academic course as an individual accommodation
How do we get there?
Various Models
• Make it affordable
– Negotiate a great price with a vendor
• Make it easy
– Simple web portal for getting and receiving
captioned media
• Crowdsourcing?
– Academic credit or work study for students
– Worthwhile project for alumni & other volunteers
• Develop an in-house service
TEDTalks:
A Crowdsourcing Success Story
• 43,490 translations
• 101 languages
• 9915 volunteer translators
Inspiring People to Use What you Build
• Evangelize – talk about the benefits
• Persuade your institution to embrace and
implement the benefits (search, translation,
interactive transcripts, etc.)
• Create a culture where anyone who is not
captioning their video is square
• Institutional policy: All video must be
accessible