DTV Audio Group at NAB 2017
In his opening remarks at the DTV Audio Group’s “Advanced Audio Production and Distribution Seminar” at this year’s NAB Show, Roger Charlesworth, Executive Director, DTVAG, noted that audio and video IP networking has suddenly become a reality for broadcast production and distribution.
After several years during which the adoption of IP transports always seemed to be just around the next corner, “There has been a lot happening in IP in the last year, particularly in IP video,” he said. “There’s one suite of standards, SMPTE ST 2110, that everybody supports, and AES67 audio is a part of that.”
Consequently, said Charlesworth, “Lots of people are going to make equipment that’s compatible.”
Thomas Edwards, VP of Engineering & Development, Fox Networks Engineering and Operations, offered a description of the SMPTE ST 2110 stack of standards, which are based on a model developed by the BBC and the Video Services Forum. He agreed that the standards process has moved forward dramatically recently. Three of the sections, 2110-10 (system timing and definition), -20 (video) and -30 (audio), passed the SMPTE final committee draft ballot in March, he reported, going forward to the final standardization stage.
ST 2110 is baked enough now that vendors can feel confident about building real products, Edwards said. The Alliance for IP Media Solutions, AIMS, has helped push these standards forward; in a recent survey, 72% of its members said they will be shipping final draft ST 2110 standards-compliant products this year.
Kevin Gross, leader of the task group that developed AES67, offered an update on the audio-over-IP interoperability standard, which was originally published in 2013. A new revision is expected to be published this year as AES67-2017, he said, to include Protocol Implementation Conformance Statement, or PICS, a 20-page checklist. A quarter of the requirements are “musts” for anyone doing a minimal implementation, he estimated.
AES67 incorporates SIP, which is used in voice-over-IP, for unicast connections. There hasn’t been a huge uptake in SIP by product developers participating in the AES “plugfests,” he observed. Gross also noted that SMPTE has yet to define connection management for ST 2110.
Kent Terry, Sr. Manager, Audio Technology, Office of the CTO at Dolby Laboratories, discussed SMPTE’s standards-based approach to the metadata that must also travel over live streaming networks. Channel-based audio today in live broadcast generally works, he said, and there has been little enthusiasm for metadata, hence little work done to standardize it thus far.
The way forward is to leverage existing standards, he said, especially the concept of Key Length Value, or KLV, in SMPTE 336, the basis of MXF and other exchange formats. Currently in committee, SMPTE 2109 will ideally describe an open framework method for sending a KLV-type container natively over IP as an RTP stream separate from the PCM audio. SMPTE 2109 is agnostic of the format — PCM, encoded — or the type of metadata, and would travel over AES67 or 2110-30, he suggested.
The FCC’s Incentive Auction is over and wireless microphone operators have lost 70 MHz of licensed spectrum. The problem is that RF mic users have increased need and decreasing spectrum, said Jackie Green, President/CTO of Alteros.
With 1,274 TV stations relocating into the lower frequencies, the remaining available spectrum will become 20% more crowded, she added, which will result in a more compromised environment.
While the FCC’s timetable allows 39 months for the TV station repack, a 10-phase process beginning September 14, 2018 and ending July 3, 2020, the new 600 MHz tenants may begin testing as soon as their allocated spectrum is vacated. Companies such as Nokia are reportedly ready with 600 MHz gear to put into operation immediately, Green said. In other words, they could potentially start tomorrow.
Green advised wireless mic operators to regularly check rabbitears.info, which is using a variety of tools to update the changes in each market’s frequency spectrum.
RF mic manufacturers offer equipment that operates in the 902-928 MHz, 2.4 GHz and 5 GHz ISM, and DECT bands, and the FCC has expanded access to 944-952 MHz and 1435-1525 MHz, with certain restrictions. Alteros has released a product that works in the unlicensed 6.5 GHz UWB band. Operators need to think about putting less critical elements into frequencies that are not in the TV spectrum, she said.
Congress has already mandated the auction of another 255 MHz of spectrum below 6 GHz, so there are more changes coming, warned Green.
Rob France, Sr. Marketing Manager, Dolby Labs, noted that, while people at the NAB Show are talking about implementing Dolby Atmos in broadcast, BT Sports in the UK is producing an average of two Atmos shows a week, covering soccer and boxing. There are three OB companies each with an Atmos-capable truck, he said, and eight more Atmos trucks are in the planning stages in Europe and China.
France went into detail about the challenges and workflows of live Dolby Atmos broadcast productions. Where Dolby Atmos broadcasts go next will be driven by the value to BT, he said. The UEFA Champions League final in the UK, at which there will be 30 OB trucks from international broadcasters including ESPN and Fox, will be the first live production where BT will make Dolby Atmos available to other broadcasters.
Jim Starzynski, speaking as chairman of the ATSC’s S34-2 technical group, reported that the group has standardized Dolby AC-4 and MPEG-H under three different papers. Korean broadcasters will go on-air using ATSC 3.0 and MPEG-H next month. Their US counterparts will begin experiments with AC-4 as soon as they are able, he said.
Switching hats, Starzynski, also chair of the AES Group for On-Line Loudness Guidelines, offered a progress report on the draft process. The group’s goal is simple, he said: take what was learned from establishing the DTV loudness guidelines and apply that to OTT. The difference is that the OTT loudness guidelines will take into consideration the behavior of mobile and fixed devices, he said.
Karl Malone, Director and Sound Designer, NBC Sports & Olympics, presented a recap of the Rio Olympics and a preview of the 2018 Winter Olympics in South Korea. Production in Rio encompassed more than 2,000 hours of Olympic coverage across 11 NBC Universal networks. NBC’s digital platforms streamed 4,500 hours of coverage, including every second of live competition.
While MADI was used in the control room in Rio, Dante IP networking was a huge success for his operation, said Malone, especially the AoIP-enabled RTS Omneo comms panels. Analog fell out of use for his operations two years ago, said Malone, who predicted that there will be almost no copper cables at the International Broadcast Center in Korea.
A final panel, featuring representatives from content producers, OTA and OTT distributors and manufacturers, weighed in on the potential for Dolby Atmos delivery. Hearing “Saturday Night Live” in Atmos was “mindblowing,” said Stacey Foster, President, Production Services, Broadway Video and Coordinating Producer for SNL. The show will be produced in 4K, HDR and Dolby Atmos beginning fall 2018, he said.
The competitive nature of content providers will ultimately drive the availability of immersive audio programming, the panel agreed. Terry Douds, Vice Broadcast Operations Supervisor at WOUB Public Media, offered a cautious note: consumers in rural areas are still listening in stereo and over-the-air.
Malone, who earlier reported that NBC Sports & Olympics produced the opening ceremonies in Rio in Dolby Atmos, shared that he would like to push the immersive format for sports broadcasts. While consumer uptake is something of an unknown, soundbars are going to help deliver Dolby Atmos in the living room, he suggested.