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Project HD: NAB Co-hosts AFD Resource Online

An occasional series spotlighting current HD projects underway across various media and media groups.

The AFD Ready Initiative is a recently added online resource for Active Format Description that is attached to the NAB Web site—an initiative that counts among its broadcast supporters Cox Broadcasting, Fox Television, Hearst-Argyle Television, NBC Universal and Tribune Broadcasting.

AFD has been standardized by the ATSC, CEA and SMPTE as a method of describing aspect ratio and picture characteristics of video signals. When AFD is included in DTV broadcasts, digital sets and converter boxes with AFD capability can automatically adjust programming for a “best match” with the aspect ratio of the display being used. AFD can also be used to manage aspect ratio at various points in the broadcast plant and distribution chain.

According to Graham Jones, NAB director of communications engineering, the online resource was devised in order to increase awareness of Active Format Description and promote its use throughout the television industry. “Leading up to, and after, the analog shutdown in February 2009, cable and satellite providers will down-convert HD broadcasts for distribution to their SD viewers. The primary goal of the AFD Ready Initiative is to drive the deployment of AFD technologies to ensure that such down-converted signals are displayed in the aspect ratio that content producers originally intended,” Jones told HD Notebook.

“The use of AFD will also be included in ‘ATSC Recommended Practice for Conversion of ATSC Signals for Distribution to NTSC Viewers,’ which is now in preparation. It’s expected to be published in the early fall. This document will provide guidance to ensure uniform and optimum program delivery of television broadcasts on both cable and satellite,” he said.

For more background on AFD, see The Reference Room article from TV Technology published in June.