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, David Klein K. “Fritz” Thompson
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 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
Overview of the Technologies
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 Server
Clients vs. Servers Server Clients 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 Browser Window Embedded Player with Controls Video Captions Links to supporting documents
Embedded Captioned Video Embed in HTML File ServerClient Video File Caption File Combine Files in Player
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