Transcript
IBE Content Management
A year in HEVC Ian Trow, senior director of emerging technology and strategy at Harmonic, looks at developments in the field of High Efficiency Video Coding over the last 12 months.
Ian Trow, senior director of emerging technology and strategy at Harmonic.
Today’s consumers have an insatiable appetite for live, video-ondemand (VOD), and OTT television content on a wide range of devices, including TVs, PCs, smartphones and tablets. However, this challenges broadcasters to deliver high-bandwidth services with limited resources. A next-generation video compression standard called High Efficiency Video Coding (HEVC) offers a solution by improving upon the current compression standard MPEG-4 AVC (H.264). Through HEVC, broadcasters can dramatically reduce the data rate needed for high-quality video coding to deliver a better video quality using the same amount of bandwidth, or the same quality using far less bandwidth. HEVC is an exciting advancement for the broadcast community, as it will enable the cost-effective delivery of live, VOD, and OTT HD services as well as Ultra HD 4K and 8K, which are just on the horizon. This article will examine the latest HEVC developments, taking a close look at the progression of the technology, royalty issues, and realworld applications.
Progression of HEVC Technology Realistically, first-generation HEVC codecs will provide a compression performance improvement of approximately 30 to 40 percent over H.264. However, that will progressively improve as the codecs become more efficient and mature. For Ultra HD applications, HEVC is likely to provide more than 50 percent compression efficiency simply because the coding for HEVC suits large spatial pictures with a lot of redundancy. In terms of technology developments over the last 12 months, HEVC has seen CODEC
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vendors exploring the potential of the compression standard to evaluate which tools offer the most benefit. HEVC encoding products are emerging for both live and filebased applications with resolutions up to Ultra HD / 4K. Many of the HEVC encoding platforms making their way to the market are software-based running on highperformance blade servers. Thus, HEVC will help foster the transition from bespoke broadcast hardware to software running on blade platforms allowing broadcast applications to gain from the enterprise trend for virtualisation. We’re also seeing that HEVC is helping drive the transition to IPbased broadcast infrastructures. Increased throughput demands for high-quality, real-time video have led to the gradual migration to broadcast infrastructures that are 75 percent based on IT equipment and 25 percent based on bespoke video equipment, a complete reversal compared with just a few years ago. IP-based infrastructures are becoming more prevalent, as are file-based asset management, particularly for 4K and Ultra HD in order to help ease broadcasters’ bandwidth issues. On the consumer side, there have been HEVC chipset developments, with several companies producing silicone for Smart TVs and STBs; however, it will take time before they’re ready to be deployed. HEVC decoders are also being rolled out. Some of today’s Smart TVs purport to have HEVC decoding capability, such as the Samsung F series, which includes a One Connect box on the back of the unit that enables consumers to upgrade their television to new Ultra HD hardware and software standards. A multicore processor is needed to perform the decoding. In addition, some tablet and Smart TV manufacturers are looking to put dedicated ASICs
(application-specific integrated circuits) into the decoding because they think there’s a performance advantage to decoding on a dedicated chipset. That’s the kind of thinking that’s going on behind products such as the Qualcomm Snapdragon. Major players in the gaming market, like Microsoft and Sony, are making noise about HEVC, but if the history of video compression technology gives any indication, there’s likely to be a bit of a waiting game before the new standard makes its way into gaming consoles, as H.264 was predominantly launched for catch-up TV services. In the game console environment, we can expect to see the same thing happen. The gaming market is still missing details about HEVC decoding capabilities and how HEVC game consoles can handle broadcast or OTT content for TV applications. There may be a marginal case for strapping extra processing capabilities to the back of Smart TVs due to the cost constraints associated with those types of viewing platforms. In the gaming market, there is a definite business case, because the processing power required for running high-powered graphics and games is directly consistent with the type of uplift being offered by HEVC. The HEVC standard provides 12 times the increase in computer memory and processing capabilities on the encoding side, and three to four times increase for decoding.
Royalty Issues Currently, MPEG LA, a group that licences patent pools covering essential patents required for use of the MPEG-2, MPEG-4 Visual, IEEE 1394, VC-1, ATSC, MVC, MPEG-2 Systems, and AVC/H.264 standards, represents a group of 25 companies that have agreed to HEVC license
IBE Content Management terms. However, there is concern about a small number of potential patent holders that are not participating in the MPEG LA agreement. Ultimately, this situation needs to be remedied. Without full participation of all the royalty holders, the HEVC standard is never going to be crystal clear. This situation is not unique. The exact same circumstances happened with MPEG-2 and H.264, and in both cases it was eventually resolved. Undoubtedly, there’s commercial pressure from other video codecs from the likes of Microsoft and Google. Thus, the existence of proprietary compression standards may hasten the progress of resolving the remaining HEVC royalty issues.
Real-World Applications A solid commercial market exists for HEVC products capable of delivering live HD, VOD, and OTT services. While the market establishes itself for 4K and Ultra HD delivery, many broadcasters are keen to experiment with using HEVC to deliver filebased assets (e.g., Netflix) or participate in proof of concept trials to associate their brand with cutting-edge technology. Last year, global satellite operator
SES powered the world’s first Ultra HD transmission using HEVC. While many live trials are taking place, there’s still a bit of scepticism with regards to the HEVC broadcast workflow, partly because of what happened with 3D. Broadcasters want to know what kind of content delivery bandwidth is going to be available in order to determine whether a full blown distribution chain for HD or Ultra HD is justified. It’s debatable whether it’s better to produce an asset in 4K, downconvert it for transmission, and then rely on up-conversion within the TV to get the resolution back up to Ultra HD 4K. The biggest market for HEVC is likely to be HD OTT services since OTT and catchup-TV costs are a huge issue affecting broadcasters at the moment. The problem with running broadcast services over the Internet is that in order to deliver a high quality of experience, a content delivery network (CDN) or a provision to cache the data is needed. Thus, most catch-up TV services are delivered via CDN. When it comes to OTT video services, most consumers are used to viewing the content at a quality level below HD and certainly not in full 1080p resolution. HEVC would allow consumers to watch OTT
services with a much higher video quality while reducing costs for content operators. The type of services that Netflix offer would be the perfect introduction of HEVC into the home. The HEVC standard will help to level the playing field between OTT/catch-up services and traditional broadcast services, which are operating over a dedicated spectrum.
Conclusion Most video compression standards have not been successful until the industry reached a point in time where it was necessary to swap out consumers’ set-top boxes; however, HEVC is different because it’s going to be used more by downloadable players than chipsets in STBs. The HEVC standard will be utilised for Smart TVs, game consoles, and web viewing, creating more of an even split between the standard’s use in software players, which are easily upgradeable, and STBs, which have legacy technologies associated with them, namely MPEG-2 or H.264 chipsets. What this means is that HEVC will likely see mass adoption more quickly than other video compression standards.
Most video compression standards have not been successful until the industry reached a point in time where it was necessary to swap out consumers’ set-top boxes; however, HEVC is different because it’s going to be used more by downloadable players than chipsets in STBs.
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