If you were planning a trip using the roadmap for UHD, there’s no telling where you would end up. Industry opinion ranges from the glass half empty pessimists who feel that the visual improvement over HD is not enough to move the needle of customer adoption, to optimistic prognosticators who feel that the transformation to UHD services with High Dynamic Range (HDR) could rival the shift from black-and-white to color.
Whatever your opinion – and just for the record, my feet are firmly in the optimist camp – we shouldn’t let disagreement over the future of UHD cloud one essential fact: It’s in the best interest of the industry to accelerate the transition to High Efficiency Video Coding (HEVC), the under-the-hood enabler of UHD deployments, regardless of operators’ plans to support the new resolution.
Here’s why: While the superior resolution of UHD can help operators drive greater customer satisfaction, the benefits of HEVC – particularly in an increasingly unicast content environment – accrue directly to the operator. The same efficient use of spectrum that supports UHD can similarly create greater operational efficiencies in operators’ existing HD deployments as well.
To understand the value, let’s look back briefly at the history of video compression and the differences in particular between H.264 and the HEVC codec, H.265. Although MPEG-1 revolutionized video and audio delivery almost three decades ago, it was MPEG-2/H.262 and later MPEG-4/H.264 that would support the growth of digital cable, including today’s HD services.
What sets HEVC/H.265 apart is the ability to leverage improved CPU capabilities and the use of advanced techniques like Coding Trees to increase encoding efficiency – a 40-50 percent bit rate reduction over MPEG-4/H.264, which itself was a 40-50 percent bit rate reduction over MPEG-2/H.262. The H.265 specification also supports up to 8K resolution UHD TV and up to 300 frames per second, providing the industry with plenty of headroom for future technical developments.
Those capabilities are key to supporting the industry’s rollout of UHD, where achievement of superior user experiences requires a vastly greater amount of information to be conveyed. But HEVC is also driving improvements in another, sometimes overlooked aspect of UHD deployment — security. Early ventures by Rogers and BT into UHD sports programming and by our own customer, Videotron, into 4K UHD STBs share a common link: The recognition that UHD is a premium content experience that can bring value to pay-TV customers. Application of specialized content protection techniques, such as the Advanced Encryption Standard (AES) with 128 bit keys, to HEVC more effectively safeguards high value UHD content.
What’s important for the industry today is that the same network efficiencies of HEVC can be used to address existing content delivery issues, as well as UHD. The increased consumption of unicast video content on handheld devices, for example, ultimately has the potential to bump up against network limitations. HEVC’s 2:1 efficiency ratio can double the amount of content that can be delivered within a given amount of bandwidth. In addition, deployment of new HEVC-compatible DVRs could offer double the storage within the same size hard drive, dramatically increasing the amount of content that subscribers could store, manage and access locally.
Of course, the rollout of HEVC will not occur in a vacuum. Operators who make the forward-looking move of deploying the new technology need to do so without impacting their existing services. This can be done seamlessly in a unicast scenario, in which HEVC streams are being delivered individually to HEVC-compatible devices.
The issue becomes more complex in the case of broadcast channels, such as linear content in today’s pay-TV lineups. When HEVC is used in a broadcast situation, only HEVC-capable devices will be able to receive and decode the signal. In these cases, operators will face the choice of replacing all of the STBs in customers’ homes, replacing only some of the STBs in each customers’ homes, or deploying new 4K UHD-capable STBs only in those home whose customers choose to view UHD content.
Operators such as Videotron and others are making 4K UHD STBs available today, creating an immediate marketplace for premium 4K content while seeding the market for mainstreaming of HEVC in the future. In my opinion, a future alternative will be for operators to enable transcoding capabilities in the home, so that HEVC can be “down converted” for delivery to non-HEVC legacy devices.
No matter what strategy is used, it’s likely we’ll remember 2016 as a year when there was significant operator activity around HEVC. While the libraries of content that will power UHD services with High Dynamic Range might be slower in arriving, the efficiencies of HEVC across a broad range of services will make it an essential part of pay-TV’s technological arsenal in the year ahead.
