by Steve Harvey.
San Francisco, CA (November 10, 2010)–With digital television now standard in the U.S., the “Innovations in Digital TV” panel at the recent AES Convention in the Moscone Center in San Francisco, discussed recent improvements at the consumer end of the chain and revealed recent technological developments in portable devices.
Tim Carroll of Linear Acoustics laid out the challenges to high-quality audio on portable devices, particularly noting the less than ideal speakers and earbuds associated with such devices, the impact of noisy environments, and the ineffectiveness of traditional broadcast processing and down-mixing techniques. Carroll advocated a hybrid approach: judicious multiband AGC pre-processing to enhance spectral content, plus the application of metadata. Dolby’s proposed nascent Portable mode looks especially promising, he said.
“You can’t process audio for mobile devices the same way as television,” agreed Sterling David of Cox Communications, who reported on a portable device study conducted with Washington, DC consumers. That study identified dynamic range as a particular problem.
Gier Skaaden of DTS noted the ability of the DTS audio codec to deliver the highest resolution audio in the “last foot” of the distribution chain. Eighty percent of consumers rely on legacy codecs, he reported, and the DTS solution can scale in real time according to bandwidth availability. “DTS is the only proprietary format able to expand from low bit rates to fully lossless,” he stressed.
The Consumer Electronics Association has been developing recommended practices related to DTV, revealed the CEA’s David Wilson. CEA-CEB11-A focuses on the perceived loudness differences between AC-3’s RF and Line modes, NTSC/BTSC and MPEG-1 Layer 2. The recommendation is for equipment manufacturers to “dial down the voltage of louder signals to match the quietest,” he shared, which, as Carroll also noted, is Dolby’s RF mode.
David Layer of the National Association of Broadcasters laid out some of the technology initiatives sponsored by the organization’s FASTROAD (Flexible Advanced Services for Television & Radio On All Devices) program. The NAB is working with two companies to develop tiny FM radio antennas for cell phone use; TV antennas are next. Syncbak is developing technology to synchronize over-the-air TV programming to broadband content in web-enabled TV devices, providing a one-to-one connection with the viewer, he reported.