HEVC is for OTT but not yet Ultra HD

Likely to become best known as H.265, HEVC has been seized upon as the enabler for Ultra HD and more immediately as the salvation for smart TVs accessing content over the Web.
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HEVC (High Efficiency Video Coding) has been one of the big stories of 2013 so far as its final ratification as the ISO/IEC MPEG standard to succeed H.264/MPEG-4 approaches. Likely to become best known as H.265, HEVC has been seized upon as the enabler for Ultra HD and more immediately as the salvation for smart TVs accessing content over the Web. That is why there have been strong rumors Apple has been waiting for HEVC ratification, likely in a month or so, as the move that will enable it to launch its long-awaited TV with the ability to deliver HD content at the current HD resolution of 720p or 1080i.

Along with Ultra HD and Web-connected TV, the third big use case for HEVC is mobile video, where by doubling the efficiency of H.264 it will allow users to download files for subsequent viewing in half the time while also improving the quality of streamed content. This enables twice as much video to be stored in the device’s limited memory, and crucially will reduce the processing load on the CPU and the drain on the battery. By improving all these measures by a factor of two with scope for further improvement, HEVC will be compelling for mobile video, and this is where it will make its first impact this year.

The major vendors in this space are ready to roll. Apple’s iPads are already HEVC-compliant, while Rovi Corporation stated at the recent Consumer Electronics Show that it is introducing an SDK (Software Development Kit) and an update to its DivX device certification that will enable third parties to provide HEVC support on their own devices. This is significant because Rovi is a leading provider of “white label” tools used by mobile device vendors to launch their own branded digital services including video delivery. Rovi’s step will therefore encourage both software and hardware vendors to accelerate their adoption of HEVC.

Apple is interested in both the mobile and connected TV dimension, and while it would be overdoing it to suggest that HEVC is the deal-breaker for Apple TV, it is an important part of its ecosystem. It is notable that while Apple has shunned the MPEG DASH adaptive HTTP streaming standard, persisting with its own HLS (HTTP Live Streaming), it has been almost a champion of HEVC. No vendor can go it alone for encoding, given the great investment involved and need for all players in the ecosystem to pull together to obtain the greatest compression efficiency possible. Over time, DASH is likely to exert an equally strong convergence pull, and even Apple will have to come on board and merge HLS with it.

Meanwhile, the same CE vendors that are embracing HEVC for smart TV also argue that it will provide the spark that ignites Ultra HD right across the ecosystem from production through contribution, distribution to the end device. Well perhaps it will, but not just yet. It is worth noting that H.264 has only recently been deployed widely in the broadcast chain, now increasingly for contribution as well as distribution. There is still even life left in MPEG-2 for broadcasting and pay TV, while the latest digital terrestrial standards, such as the DVB-T2 currently being widely deployed in Europe, is aligned with H.264/MPEG-4.

It is true that HEVC has been developed with Ultra HD in mind, at any rate the 4K version currently being hyped, at 3840 x 2160 resolution. For example, French vendor ATEME has demonstrated a device that encodes video at 3840 x 2160p at 60fps, at an average bit rate of 15Mb/s, due to ship October 2013. But this is very much aimed at trials at this stage, and given the steps involved, there is no way that we will see 4K widely deployed for streamed broadcast services until at least 2016 and probably a year or two later. We will have to wait almost as long as that for HEVC to enter the broadcast chain, but it will make a much faster impact for mobile video.