Broadcasting is in a transition that goes beyond the mere conversion of analog systems to digital platforms. Various initiatives are leading the way to new methods for content delivery, with emerging solutions for both broadcast and content production. This and future columns will look at the expected changes in the ecosystem for content development and delivery.
The next-generation of broadcast
Last fall, the ATSC published its “Final Report on ATSC 3.0 Next Generation Broadcast Television,” describing likely methods of enhancing broadcast TV with next-generation video compression, transmission and IP technologies. The report presents a comprehensive view of new elements that likely will constitute tomorrow's broadcast systems, including compression, modulation, transmission and hybrid architectures.
The latest MPEG compression, High Efficiency Video Coding (HEVC), shows performance that is substantially better than H.264/MPEG-4 AVC coding, with an efficiency that would allow more content bandwidth, i.e., higher throughput or higher video resolution. Studies suggest that HEVC could offer at least a 4X improvement in efficiency over that of MPEG-2. Higher resolutions receiving serious consideration include 8K (7680 × 4320) and 4K systems (3840 × 2160).
The ATSC report received little input on essence-related metadata, which suggests the topic is not high on the list of developers' priorities. The workflow and carriage considerations of metadata should not be trivialized, as more interactivity is being demanded by content consumers, and that requires an efficient infrastructure for developing and handling this component.
At the physical layer, modulation schemes that offer higher efficiencies (and/or performance) than existing technologies are being considered, including new error-correction coding, which could lead to a new, non-backward-compatible transmission system. New ideas also include adaptive transmission technologies, in which transmission characteristics and the network topology can be changed depending on receiver usage, but these have not progressed past the concept stage.
New content delivery options
Hybrid broadcast is a concept that allows a more-connected television service, including hybrid on-air/online content delivery, user interactivity, adaptive configuration and other enhancements. Such a system, offering an integrated, networked environment, has been tried in parts of the world, and likely will become a key part of broadcasting. Going beyond the current elements of Internet TV, hybrid broadcasting would enable a more efficient use of both wireless and wired communications channels for delivering content. Hybrid broadcasting would integrate OTA content with content delivered out-of-band, e.g., by Internet. (See Figure 1.)
One version of hybrid broadcasting being discussed by some broadcasters is a hybrid heterogeneous network, in which digital television broadcasting is overlaid onto the wireless telephony infrastructure. Such a system would integrate the one-to-many broadcast transmission of video with the many-to-many connectivity of wireless Internet and cellular networks.
On the Internet side, many players currently are trying out new methods for distributing and receiving content, and lessons learned there will help define efficient hybrid networks.
Apple is thought to be planning an integrated television set to replace its current AppleTV set-top box, possibly equipped with the digital assistant that runs on the newest iPhone. Likewise, Sony is believed to be building a content distribution network. Google is redefining its GoogleTV offering, and many new televisions already have access to content from providers Netflix and Amazon; TiVo has similar built-in connectivity to Hulu, Amazon and Netflix. Microsoft has teamed up with Comcast and Verizon FiOS, as well as a variety of content providers, allowing subscribers to watch live TV and on-demand video via the Xbox 360.
The common element in all of these developments is that content increasingly will become available from a multitude of sources, and broadcasters need to move quickly to offer a compelling alternative.
Repurposing of captions
Providing captions is another area that is affecting content distributions. The Twenty-First Century Communications and Video Accessibility Act of 2010 (CVAA), signed into law by President Obama, requires the FCC to extend the Television Decoder Circuitry Act of 1990 (closed caption law), and its updates, to require the provision of closed captioning on video programming delivered using IP that was published or exhibited on television with captions. The proposed rules also require video programming owners to send required caption files for IP-delivered video programming to video programming providers and distributors along with program files. Furthermore, the proposed rules require the appropriate parties to reliably encode, transport, receive and render closed captions of video programming delivered using Internet protocol. The CVAA requirements thus mean that content developers and distributors must now build into their workflow methods that ensure that captions will be properly delivered and available to other content presenters.
A new global transmission system
It may be closer than some once thought. Late in November, the House Energy and Commerce Subcommittee on Communications and Technology approved the Jumpstarting Opportunity with Broadband Spectrum (JOBS) Act of 2011. The legislation is the culmination of hearings and bipartisan negotiations to use voluntary incentive auctions to make more efficient and effective use of the public's airwaves, and support the establishment of a nationwide, interoperable, broadband public safety network. One component of the bill proposes “a waiver of the broadcast service rules of the FCC to permit the licensee, subject to interference protections, to make flexible use of the spectrum assigned to the licensee to provide services other than broadcast television services.”
The waiver provision appears to allow broadcasters the option of transmitting non-backward-compatible signals without a need to service existing DTV viewers, as long as at least one program is sent for free. This element could pave the way for alternate television transmission systems to be rolled out quickly. At press time, the House bill had been bundled with provisions for middle-class tax relief, and the new bill passed the House 234-193. Although it may not survive a presidential veto, there could be sufficient “line item” support for the service-rules waiver to re-emerge in other legislation.
Change is happening at the international level as well. Television broadcasting executives gathering in China last November agreed that a global approach to the future of terrestrial television broadcasting is the “ideal method to avoid competing standards, overlap and inefficient deployment of new services.”
Delegates to the Future of Broadcast Television Summit held in Shanghai officially expressed unified support for a joint declaration calling for global cooperation to define new requirements, unify various standards, and promote sharing of technologies to benefit developed and under-developed countries.
Supporters of the declaration agreed to three major initiatives: defining the requirements of future terrestrial broadcast systems, exploring unified terrestrial broadcast standards and promoting global technology sharing.
Aldo Cugnini is a consultant in the digital television industry.
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