Techniques for Creating Accessible, Closed Captioned Web-Based Video
California State University - Northridge
22nd Annual International Technology and 
Persons with Disabilities Conference

Los Angeles, California
March 22, 2007

http://disability.law.uiowa.edu/lhpdc/publications/kleinpubs.html
Interactive
•	Who are you?
•	Why are you here?
•	What would you like to know?
•	What are your expectations from this workshop?
Overview
•	Introduction to accessible web-based video
•	Creating captions with MAGpie (activity)
•	QuickTime (activity)
•	(Break?)
•	Windows Media Player (activity)
•	Using a Flash player (activity)
•	Embedding content in a web page 
•	Process and Compression
Introduction
•	Law, Health Policy & Disability Center

Grant-funded research, technical support, & training

Our Needs
•	Accessible web-based training
•	Quality video
•	Closed captions
•	Transcripts
•	Supporting documents (PowerPoints, Handouts)
•	Different formats 
•	QuickTime
•	Windows Media Player
•	Flash)
•	Efficient production, development, and deployment
Our Video
•	http://disability.law.uiowa.edu/dpn/video/
•	Over 100 hours of online video for training
•	Mostly talking heads
Characteristics
•	User choice
•	Start with most accessible player – Flash 
•	Multiple players and configurations
•	Embedded vs. Standalone players
•	Automatic play vs. press a key to start
•	Resizable Players
•	Uncaptioned versions
•	Platform agnostic (Windows, OS X, Linux)
•	Available metadata, transcript, supporting documents

Players
•	QuickTime
•	Windows Media Player
•	Real Player
•	Flash Player(s)
•	Others
The Technologies
•	Clients and servers
•	Plugins or whatever
•	Downloading
•	Embedding video in web pages
•	Flash
Clients vs. Servers
Clients vs. Servers
Server
•	Server 
•	Stores HTML, video, caption text, other files
•	Files can be stored on different servers
•	Files
•	HTML page
•	Video file
•	Caption text file
•	Combining file
•	Supporting files (transcript, handouts, PowerPoint)
Client 
•	Displays HTML in browser
•	Launches players
•	Assembles and displays the pieces 
•	Video
•	Caption text 
•	Video player and its controls
•	HTML and surrounding content

Client View
Embedded Captioned Video
Captioning Technologies
•	Open formats
•	XML 
•	Extensible Markup Language
•	SMIL
•	Synchronized Multimedia Integration Language
•	DFXP
•	Distribution Format Exchange Profile of the timed-text authoring format (TT AF)
•	Proprietary formats
•	QuickTime caption file
•	Apple proprietary format
•	SAMI
•	Microsoft® Synchronized Accessible Media Interchange 
Download and Play
•	Wait for file to download before playing
•	Can be a long time
•	Freezes possible but can play back without freezes
•	Download and store for later play
•	No copy protection
•	Archive only

Streaming
•	Short wait for start of video
•	High bandwidth required
•	Fast server or multiple servers
•	Special network settings may be needed (multiple connections)
•	Fast connections
•	Freezes not uncommon
•	Problems at client end (firewalls)
•	Can copy protect
•	Required for live video
•	Possible for archived video

“Progressive download”
•	Short wait for start of video, depending on bandwidth
•	Slow connection possible
•	Freezes possible but can be replayed without freezes
•	Download and store for later play
•	Copy resistance
•	Archive only

Open Captioning
•	Simpler
•	Smaller file size
•	Embedded (burned in)
•	Static
•	May be hard to read
•	Doesn’t compress well
Closed Captioning
•	Captions can be closed
•	Benefit for people who would be distracted by captions
•	Not much other difference on the Web