WHYY Digital Datacasting for Enhanced Television

In this use of datacasting, extra information is sent along with a live, standard-definition program to provide a richer experience. As you are watching the show normally, a special notification, called a trigger, will appear in the corner of the screen. You can then press a button on your remote control, and your screen will look similar to this:

The show will continue running in the corner and there will be additional information and interactive content around it. The content and navigation is very similar to using the World Wide Web.

WHYY was one of the test stations in spring 2001, when PBS broadcast several episodes of its popular program, Scientific American Frontiers, with enhanced content. WHYY and PBS are continuing to examine and test this new technology.

Technical Information

Producing ContentÊÊThe specification for this format is determined by ATVEF (Advanced Television Enhancement Forum). The enhanced content is actually created using the same HTML format that is employed for web pages. However, the are restrictions on some of the tags and types of media you can use. The full specification can be found here.

ReceptionÊÊThe user must have a special set-top box that can detect the enhancement triggers and then format the enhanced content for the TV set. A remote control is also needed for navigation. Several manufacturers are creating set-top boxes that support the ATVEF spec.

Web Links

ATVEF - The offical Advanced Television Enhancement Forum website

ETV Cookbook - Great site about Enhanced Television

Enhancing TV with ATVEF - In-depth article by Jason Steinhorn and Mark Kohler