The HEVC/H.265 standard is now officially finalized, paving the way for broader commercialization in products in the near future. Back in September of 2012, I published a post introducing HEVC/H.265, a new video codec that offers approximately twice the efficiency of H.264. A draft specification for HEVC was released in July 2012 by the JCT-VC, a joint collaborative group co-sponsored by MPEG and the ITU. And last Friday, the ITU announced that HEVC had received first stage “consent” approval. Simultaneously, MPEG announced that HVEC had achieved Final Draft Internal Standard (FDIS) status. What does this mean?

HEVC is now fully baked and we will soon be seeing wider industry adoption!

It is important to note that the current HEVC specification only describes profiles for single-view 8-bit and 10-bit video with 4:2:0 subsampling. Extensions are in progress for 4:2:2 and 4:4:4 color sampling as well as multi-view (3D). Until these extensions are ratified next year, H.265 will not achieve full functional parity with H.264.

Because HEVC is more complex computationally, adoption will depend on continued increases in processing power and battery power. Although some current mobile devices may be able to decode HEVC in the future simply by updating their software, HEVC will put a huge strain on processors and battery life. For many applications, hardware implementations will be optimal, and many hardware vendors have announced chips that will support H.265. For example, at CES 2013 Broadcom showed the BCM7445, an HEVC decoder chip that will be incorporated into next generation home gateway devices in mid-2014.

Broadcom BCM7445 at CES 2013

But as with any codec transition, consumer adoption will depend on support across the value chain:

  • Consumer viewing devices will require updated software or hardware to decode HEVC
  • Content owners and distributors will need to create and offer HEVC-encoded content for distribution
  • Content distribution networks, such as cable operators, will need to update their delivery infrastructure to support HEVC

Unfortunately, these barriers to adoption are significant. That’s why most of us are still watching MPEG-2 on TV, even though H.264 was ratified several years ago. Still, finalizing the specification is an important first step towards adoption. And HEVC offers many benefits to broadcasters and content owners. As with 4K and Ultra High-Definition Television (UHDTV), HEVC is an important building-block in the next wave of high resolution imaging.

What the world needs now is… a new video codec? Back in 2004, when most of us video geeks were trying to figure out how to make H.264 work in the real world, plans were already afoot to develop its replacement. In case you didn’t notice, a draft specification for H.265 — also known as HEVC, which stands for High Efficiency Video Coding — was released in July by the JCT-VC, a joint collaborative group co-sponsored by MPEG and the ITU. The main benefits of HEVC are as follows:

  1. Greater Efficiency. H.265 should require only half the data rate of H.264 to deliver equivalent perceived quality.
  2. Increased Spatial Resolution. Supported image sizes span from as small as QVGA (320×240) all the way up to 8K (7680×8320) for UHDTV.
  3. Improved noise level, color gamut, and dynamic range as compared to H.264.
  4. Improved methods for parallel processing.

In subjective testing, HEVC has delivered equivalent perceived image quality at half the data rate, when compared to H.264 (High Profile). This means that HEVC could enable web and mobile devices to consume one half their current network bandwidth when streaming video. Or this increase in efficiency could be used to significantly improve image quality at the same data rate. Either way, H.265 will be a boon to web and mobile delivery.

Comparison: H.265 and H.264
(Source: Qualcomm at 2012 Mobile World Congress)

How does HEVC accomplish this drastic increase in efficiency? Although based on H.264, HEVC offers many small tweaks that add up, including the following:

  • HEVC replaces macroblocks with a more efficient (but also complex) hierarchical system for partitioning frames.
  • HEVC provides larger block sizes for higher coding efficiency.
  • HEVC supports tiling, allows multiple encoder instances to work on the same frame simultaneously.
  • HEVC supports wavefront parallel processing, so multiple threads can process different slices of frames more efficiently.
  • HEVC is progressive-scan only, simplifying decoder implementations.
  • HEVC includes entropy coding algorithmic enhancements that enable hardware decoders to run more efficiently.
  • HEVC includes higher precision filtering for improved motion compensation.

HEVC is expected to be fully ratified and published by early 2013. And, although chip vendors may not finalize hardware implementations until the standard is fully baked, software implementations will likely see commercialization in 2013. At IBC earlier this month, several vendors publicly demonstrated HEVC prototypes and announced HEVC support in future products:

What’s the catch? Licensing is still an unknown at this point. MPEG-LA has recently issued a call for patents that read on HEVC, so there is a possibility that H.265 will require a licensing fee. While MPEG-LA has not charged a license for H.264 when used to distribute video for free on the web, other uses of H.264 have incurred licensing costs. In any case, it seems likely that most H.265 implementations will require licensing fees.

There’s never a good time to introduce a new video codec, but it’s easy to argue that HEVC comes at just the right time. Video distribution now consumes the vast majority of all network traffic. Video-capable smart phones and tablets are ubiquitous. Unlimited mobile data plans are a thing of the past. Here’s hoping that licensing hurdles do not prevent the adoption of a new technology whose time has come!