Video & Movies: The Video Codec Engine, UVD3, & Steady Video 2.0

When Intel introduced the Sandy Bridge architecture one of their big additions was Quick Sync, their name for their hardware H.264 encoder. By combining a specialized fixed function encoder with some GPU-based processing Intel was able to create a small, highly efficient H.264 encoder that had quality that was as good as or better than AMD and NVIDIA’s GPU based encoders that at the same time was 2x to 4x faster and consumed a fraction of the power. Quick Sync made real-time H.264 encoding practical on even low-power devices, and made GPU encoding redundant at the time. AMD of course isn’t one to sit idle, and they have been hard at work at their own implementation of that technology: the Video Codec Engine (VCE).

The introduction of VCE brings up a very interesting point for discussing the organization of AMD. As both a CPU and a GPU company the line between the two divisions and their technologies often blurs, and Fusion has practically made this mandatory. When AMD wants to implement a feature, is it a GPU feature, a CPU feature, or perhaps it’s both? Intel implemented Quick Sync as a CPU company, but does that mean hardware H.264 encoders are a CPU feature? AMD says no. Hardware H.264 encoders are a GPU feature.

As such VCE is being added to the mix from the GPU side, meaning it shows up first here on the Southern Islands series. Fundamentally VCE is very similar to Quick Sync – it’s based on what you can accomplish with the addition of a fixed function encoder – but AMD takes the concept much further to take full advantage of what the compute side of GCN can do. In “Full Mode” VCE behaves exactly like Quick Sync, in which virtually every step of the H.264 encoding process is handled by fixed function hardware. Just like Quick Sync Full Mode is fast and energy efficient. But it doesn’t make significant use of the rest of the GPU.

Hybrid Mode is where AMD takes things a step further, by throwing the compute resources of the GPU back into the mix. In Hybrid Mode only Entropy Encode is handled by fixed function hardware (this being a highly serial process that was ill suited to a GPU) with all the other steps being handled by the flexible hardware of the GPU. The end goal of Hybrid Mode is that as these other steps are well suited to being done on a GPU, Hybrid Mode will be much faster than even the highly optimized fixed function hardware of Full Mode. Full Mode is already faster than real time – Hybrid Mode should be faster yet.

With VCE AMD is also targeting Quick Sync’s weaknesses regardless of the mode used. Quick Sync has limited tuning capabilities which impacts the quality of the resulting encode. AMD is going to offer more tuning capabilities to allow for a wider range of compression quality.  We don’t expect that it will be up to the quality standards of X264 and other pure-software encoders that can generate archival quality encodes, but if AMD is right it should be closer to archival quality than Quick Sync was.

The catch right now is that VCE is so new that we can’t test it. The hardware is there and we’re told it works, but the software support for it is lacking as none of AMD’s partners have added support for it yet. On the positive side this means we’ll be able to test it in-depth once the software is ready as opposed to quickly testing it in time for this review, however the downside is that we cannot comment on the speed or quality at this time. Though with the 7970 not launching until next year, there’s time for software support to be worked out before the first Southern Islands card ever goes on sale.

Moving on, while encoding has been significantly overhauled decoding will remain largely the same. AMD doesn’t refer to the Universal Video Decoder on Tahiti as UVD3, but the specifications match UVD3 as we’ve seen on Cayman so we believe it to be the same decoder. The quality may have been slightly improved as AMD is telling us they’ve scored 200 on HQV 2.0 – the last time we scored them they were at 197 – but HQV is a partially subjective benchmark.

Finally, with Southern Islands AMD is introducing Steady Video 2.0, thesuccessor to Steady Video that was introduced with the Llano APU last year. Steady Video 2.0 adds support for interlaced and letter/pillar boxed content, along with a general increase in the effectiveness of the steadying effect. What makes this particularly interesting is that Steady Video implements a new GCN architecture instruction, Quad Sum of Absolute Differences (QSAD), which combines regular SAD operations with alignment operations into a single instruction. As a result AMD can now execute SADs at a much higher rate so long as they can be organized into QSADs, which is one of the principle reasons that AMD was able to improve Steady Video as it’s a SAD-heavy operation. QSAD extends to more than just Steady Video (AMD noted that it’s also good for other image analysis operations), but Steady Video is going to be the premiere use for it.

Display Tech, Cont: Fast HDMI PCI Express 3.0: More Bandwidth For Compute


View All Comments

  • Scali - Monday, December 26, 2011 - link

    Lol, how's that, when I'm the one saying that AMD's cards are the best performers in Crysis 2?
    I'm neutral, a concept that is obviously alien to you. Idiots...
  • Scali - Monday, December 26, 2011 - link

    Heck, I'm also the guy who made Endless City run on non-nVidia cards. How does that make me an nVidia fanboy? Reply
  • CeriseCogburn - Thursday, March 08, 2012 - link

    That's sad when an nvidia fanboy has to help all the amd fannies with software coding so they can run a benchmark, then after all that work to help the underprivileged, nothing but attacks after the facts... finally silence them.
    It's really sad when the truth is so far from the pop culture mind that actually speaking it is nearly forbidden.
    Thank you for helping them with the benchmark. Continue to be kind in such ways to the sour whining and disgruntled, as it only helped prove how pathetic amd dx11 was...
  • james007 - Friday, December 30, 2011 - link

    This sounded like such an awesome card and I was psyched to get it the moment it comes out -- until reading the part about dropping the 2nd DVI port. A DisplayPort-to-SLDVI doesn't do it, for me, because my desktop has to drive two 30" displays. In fact, I would love to be able to drive a third display so I can have a touch-screen also. My current (previous-generation) VDC does drive both displays just fine.

    This does not seem like such an infrequent requirement, especially for high-end users. Why would they drop the ability to drive the 2nd display? !!!

  • The_Countess666 - Saturday, December 31, 2011 - link

    not trying to sell you anything but, HDMI to dual-link dvi does exist (see link, or google yourself for other shops).

    and these cards do have 1 HDMI-out so that should work for you.
  • Penti - Wednesday, January 04, 2012 - link

    It's the IHV that makes those decisions any way, just because it's not on a reference card doesn't mean they won't show up or that you can't build a card with it. But the HDMI supports more then 1920x1200 finally on this card any how. I guess they could deliver a card with the old type of DVI>HDMI adapters. Obviously opting for HDMI and multidisplaycapable displayport 1.2 makes more sense though. It's been around for years now. Reply
  • Penti - Wednesday, January 04, 2012 - link

    Just make sure you actually has the number of connections you need when buying the card, many 7970 bords only appear to support single-link DVI on the DVI-connector. Reply
  • poordirtfarmer2 - Wednesday, January 04, 2012 - link

    Enjoyed the article.

    So this new 79XX architecture is about a GPU architecture that’s also good for “compute work”. The reference to NVIDIA ‘s professional video cards (Quadro ; Telsa), implies to me that this might mean video cards viable for use both in gaming and in engineering / video work stations.

    I’m not a pro, but do a lot of video editing, rendering and encoding. I’ve avoided dedicating a machine with an expensive special purpose QUADRO video card. Am I reading the wrong thing into this review, or might the new 79XX and the right driver give folks like me the best of both worlds?
  • radojko - Thursday, January 05, 2012 - link

    UVD 3 in NextGen is a disappointing. Nvidia is two generation in front with PureVideo HD 5. Reply
  • psiboy - Monday, January 09, 2012 - link

    Well Mr Ryan Smith I must ask why the omission of 1920 x 1080 in al lbenchmarks... given that almost every new monitor for quite some time has been natively 1920 x 1080... what is it with you guys and Tom's lately.. you both seem to have been ignoring the reality of what most of your readers are using! Reply

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