H.264 DXVA Benchmarks: QuickSync vs UVD 2.2 vs VP4 vs VP5

[huhn]

Or OpenCL/CUDA.
pretty much sure we will get this feature for free.

[Yups]

CUDA is Nvidia only and for HEVC decoding Intel surely won't use OpenCL. They made it clear in the past that execution units are used for this as Quicksync doesn't support it in the current hardware. EUs are part of the (GPU) hardware so the comment from clsid is clearly nonsense.

[NikosD]

Exactly (I would give a point to OpenCL, although only AMD has clearly said that will follow this path)

[nevcairiel]

Intels hardware decoder is quite flexible, I bet they can at least do parts of the decoding process in hardware, and the remaining parts in the EUs or on the CPU. We'll see how it performs once someone implements it, but for me it'll be a while since I'll be out of the country for a couple weeks soon, and somehow I doubt someone else will beat me to it, its quite a complex endavour and entirely new code, can't steal it from some place.

[GTPVHD]

https://software.intel.com/en-us/forums/topic/499189

Intel Core Processor platforms currently do not have fixed function HW HEVC codec capability. This is a feature that may be supported in future Intel Processors. On that note, there are plans to release a "hybrid" (utilizing EUs of the Core Processor graphics unit) HEVC decoder later this year.

You won't see power efficient full HEVC hardware decoding until Skylake, even Broadwell does not support full HEVC hardware decoding.

[nevcairiel]

We're all well aware that there is no full fixed function decoding of HEVC, as discussed just a couple posts above.
This is the hybrid variant, which off-loads certain tasks to the hardware.

[Yups]

Originally Posted by nevcairiel

We're all well aware that there is no full fixed function decoding of HEVC, as discussed just a couple posts above.
This is the hybrid variant, which off-loads certain tasks to the hardware.

Exactly this. We knew since months that QS of Haswell doesn't support it. The Intel answer is old, already linked here and known. We are happy enough that it works via the shader somehow. Not as power efficient and fast as a pure fixed function solution but it should help to lower the CPU dependence, especially for slower mobile Dualcore systems this is important.

[NikosD]

Originally Posted by nevcairiel

Intels hardware decoder is quite flexible, I bet they can at least do parts of the decoding process in hardware, and the remaining parts in the EUs or on the CPU.

It seems that no part of the decoding process is going to be executed in fixed-function HW decoder (QuickSync), although as nevcairiel has said, it is quite flexible (but probably not enough for HEVC decoding).

VLD will be done by CPU and the other parts by EUs.

I think that is what GTPVHD wanted to say.

Originally Posted by Yups

Not as power efficient and fast as a pure fixed function solution but it should help to lower the CPU dependence, especially for slower mobile Dualcore systems this is important.

Unfortunately, my dual core Pentium processor doesn't have HEVC DXVA enabled.

[Yups]

There are lots of mobile Core i3, i5, i7 2/4 low TDP/clocked models in the market. Not sure if it's intended that Pentium models don't have HEVC enabled, if this is the case Intel should make it clear in their changelog. You could try to ask them in the Media SDK forum. In their graphics section I doubt you will get a useful answer.

[NikosD]

Their excuse could be "Intel HD Graphics" with only 10 EUs, that all Pentium iGPUs have.

On the contrary, most - if not all - Core iX processors have 20 EUs, like the ones you mentioned above.

But for Pentiums, is more useful and necessary to have GPU support for HEVC decoding, due to slower CPU performance compared to other Core iX dual cores.

[vortex_hl]

fyi geforce 340.43 drivers support HEVC_VLC_Main profile on GTX 750 Ti

[NikosD]

Very interesting.

It seems that Nvidia with VP6 is closer to Intel than ever.

[Sulik]

NikosD: any plans to include VP6 numbers in your benchmark results ?

[NikosD]

If I had one, I would do it immediately

[Anteys]

Unless I'm misinterpreting something, my Titan with VP5 on 340.43 shows the same support for HEVC_VLD_Main:

[NikosD]

Then I'll have to check my poor GT610 with VP5, to see if HEVC_VLD_Main depends on fixed-function HW (VP5&VP6) or as I suspect, on the number of shaders.

Which means that my card - GT610 - won't have it.

Wait just for 10 min.

Update:

Unfortunately I was right

[NikosD]

Now, only one more test is missing.

A VP4 card in the middle or upper class, like the popular GT440 or better, in order to test if VP5 or VP6 has anything to do with HEVC_VLD_main, or it is something about shaders and CPU only (as I suspect)

Of course, marketing reasons could stop Nvidia of installing HEVC_VLD_Main on older Fermi cards with VP4, even if Fermi cards with a lot of shaders, could be capable of running this mode.

Intel for example, decided to remove HEVC_VLD_Main support from Haswell Pentium/Celeron for marketing reasons.

[P.J]

Wow, so my 750 Ti and Intel HD 4400 supports HEVC too
Can't wait to get the latest driver

But how to test it? any HEVC DxVA decoder??

[NikosD]

This is not a good sign.

Intel cut every codec to 1080p with latest beta driver 3652!

[Shiandow]

Originally Posted by NikosD

Now, only one more test is missing.

A VP4 card in the middle or upper class, like the popular GT440 or better, in order to test if VP5 or VP6 has anything to do with HEVC_VLD_main, or it is something about shaders and CPU only (as I suspect)

I haven't really been following the discussion, but I happen to have a GTX560Ti, which is a VP4 card. So does this screenshot help?


Nvidia GTX560Ti, driver version 335.23.
Windows 7 x64 SP1.
Same result after updating the driver to 340.43