Audio Video News

No, you can’t get Ultra HD via antenna yet, but the technology has just gotten its first successful test broadcast in Baltimore. The test used Technicolor’s ATSC 3.0 test platform to send UHDTV through an experimental transmission system from Sinclair Broadcast Group, owner of more than a hundred U.S. TV stations. The platform is based on open standards including SHVC video compression, MPEG-H audio, and MPEG-MMT signal transport. It is designed for phones and tablets as well as traditional antenna-TV reception.

Unlike conventional DTV broadcasting, which is subject to an all-or-nothing “cliff effect,” ATSC 3.0 uses SHVC (or Scalable High-efficiency Video Coding) to break up the video bitstream into subsets that add layers of quality. The system can adapt to a weak network connection by selectively dropping subsets to reduce frame rate, resolution, or bandwidth without interrupting service. Even if a device can’t get the full UHDTV packet set, it still might receive HDTV subsets with improved dynamic range, higher frame rates, and larger color bit depths. In the worst-case scenario, the picture might drop out, but audio would remain.

Technicolor’s Alan Stein, who managed the historic event, explains it in more detail: “The test used spatial scalability, sending a 1080p HD base layer video signal plus audio, and a separate 4K enhancement layer video signal. The base layer was received and played back by mobile devices. Both layers were received and combined for playback by the fixed Ultra HD devices.”

Though the current version of ATSC 3.0 is limited to 4K, future versions may go higher. “SHVC would be an efficient technology to extend the system to 8K in a backward compatible way,” says Stein.