AMD Polaris (Radeon RX 4xx) H265 Encoding Samples

[KarMa]

The R9 290 has support for VCE 2.0.

https://en.wikipedia.org/wiki/Video_Coding_Engine#VCE_2.0

I have a RX 460 and can't even seem to get B frames to work with H.264, let alone anything HEVC. Tried both OBS Studio and A's Video.

[Roph]

Polaris doesn't support B-frames, it's a hardware regression. Though it does do better motion prediction which partially makes up for it.

[KarMa]

Polaris doesn't support B-frames, it's a hardware regression. Though it does do better motion prediction which partially makes up for it.

Not too happy to hear this as that's where most of the compression is had. Maybe the previous VCE had bad b-frame usage causing pulsing, and they just did not want to deal with it or improve it. Or it took up too much space on the die. Anyway that's a pretty big regression in my eyes.

At least now I'll stop trying to make b-frame work. Thanks.

[Roph]

I'm not very familiar with VCE 2 or 3's capabilities but VCE 4 (polaris) vs VCE 1 (7000 series) is a huge improvement. Neither support b-frames, but for example after testing I changed my 540p H.264 preset from ~960kbit/s to ~650kbit/s for the similar quality when going from a 7770 to a 470.

It may be that VCE 3 (tonga, fijii aka 285/380, fury) may be the best quality H.264 encoding from AMD.

[greenmeister]

I'm waiting for the A's Video Encoder 6.0.7, I hope this version include the Polaris HEVC encode.

[Roph]

I doubt it, AMD still hasn't updated their media SDK to support HEVC or 2-pass encoding on polaris: https://github.com/GPUOpen-LibrariesAndSDKs/AMF

They initially posted the SDK, but it's been stagnant since. View the issues for requests about HEVC or 2-pass support.

Until AMD provides support in their SDK, we won't get any proper software support in tools like A's convertor.

[KarMa]

Info on all the VCE versions, and what models support what.

https://github.com/Xaymar/obs-studio_amf-encoder-plugin/wiki/Hardware,-GCN-and-VCE-Limits

[Roph]

It's getting quite frustrating that AMD still won't support HEVC / 2-pass on their SDK for polaris GPUs. These cards are now over 6 months old.

For comparison, Pascal HEVC encode was supported in Nvidia's SDK before the cards were even released.

I have to say, if you are looking for a card to encode video, just go with Nvidia. The Geforce 1050 is looking ever more attractive since I can actually use its advertised features.

[KarMa]

Pretty much.

At least I got my 460 more for video games over video encoding. But sucks trying to record any games with H.264 1080p/60fps with near transparent quality, often averaging above 50Mbit with Constant QP (I=18-20, P=20-22, No B Frames). Also seems to have blocking in darker scenes.

6 months is a long time to go without support considering they hyped the HEVC encoder at the RX 480 launch. https://www.youtube.com/watch?v=vFJXGQ4nL8w

[Selur]

Do they support 2pass encoding for AVC?

[Roph]

They don't support 2-pass encoding at all yet.

[Selur]

Okay, sounded like they did for AVC which surprised me since I have never heard or seen a hardware encoder chip (which isn't just a software encoder on a chip) which supports 2pass encoding. (-> I doubt you will get 2pass encoding from an en-/decoder chip which is normally featured on consumer graphics card.)
The thing to remember is that those encoders from NVIDIA and AMD are not GPU encoders as one would expect, but they are additional encoder (and decoder) chips on the graphic card, so unless someone messed up on release it's normally not really that one should expect a change at the SDK unless a new chip revision arrives. The chips interfaces are normally fixed and thus their capabilities are fixed.

[Roph]

AMD's mentioned 2-pass support and explained that it can greatly improve live-streaming quality in their press slides, so I'm guessing it's unlikely that if 2-pass is ever supported / exposed in their SDK you'll be able to do a traditional 2-pass where you pass over the WHOLE file and then do the actual encode.

I'm guessing it will be more like VBR but with a large lookahead buffer. I.e. it'll "2-pass" over a few seconds or so, perhaps configurable by the end user. We'll see. It'd be nice if AMD would explain it, or better yet, support it To my knowledge they've never confirmed if it's just for AVC or HEVC, or both.

[Selur]

btw. are there any command line encoders which support the amd polaris cards?

[Roph]

Yes, there's VCEenc (japanese) but it's woefully outdated. It's not been updated to use AMD's new SDK.

[Selur]

and thus it doesn't support the polaris card (at least mine isn't detected; check-vce reports: System has no GPU supporting VCE.)

[Roph]

Make sure you have the latest (though still old) 2.0 binary. VCEenc works on my RX 470, I was using it to test out / prove that polaris actually has a regression in that it does not support B-frames.

[Selur]

--version returns:

VCEEncC (x64) 2.00 by rigaya, build Jun 25 2016 20:05:50
, avs, vpy, avqsv [H.264/AVC, MPEG2, VC-1, WMV3]

but --check-vce returns:

System has no GPU supporting VCE.

Installed driver version is 21.19.164.257 from 23.11.2016 which is the latest afaik,....

[Roph]

Don't know then, I tried a VCEenc test on my 470 with 2.0 here: http://forum.doom9.org/showthread.php?p=1780533#post1780533

[Selur]

There you used,.. "VCEEncC 1.03v2" -> will test older versions tomorrow (strange is also mentions VCEEnc 2.00 (x64))

[Roph]

That's because staxrip uses an outdated binary, I dropped the latest 2.0 one in but staxrip doesn't know that. It was 2.00

[Selur]

No luck here. VCEEncC doesn't recognize my card.

[Selur]

Found the problem,.. VCEEnc does only detect the card when it is connected to the main display. So for me I need to connect a second monitor and make that to monitor to be my main monitor, since the RX 460 isn't capable to support my usual main monitor, since that would require two displayports.

[FluffyDiscord]

Can I get the HEVC test transcoder version, please?

[ezcapper]

maybe this will be interesting to some people, AMD released 4k h265 encoding driver, but limited. You can record desktop, etc, but not sure what else. it's called ReLive:
https://www.youtube.com/watch?v=CdvZeQfhWXo

Edit: okay, looks like maybe compatible with OBS, so very good if true:

https://github.com/Xaymar/obs-studio_amf-encoder-plugin/releases/tag/1.4.3.3

xaymar really did great job

[KarMa]

Ay finally. Doesn't look as customizable as OBS Studio but it's something. Thx ezcapper.

Edit: Yeah looks like only ReLive can encode HEVC on the RX cards. https://obsproject.com/forum/threads/amd-advanced-media-framework-encoder-plugin-for-o...35#post-257737

[Selur]

The main problem with AMD for me is that there is no command line encoder like VCEEncC which supports the new SDK, exposes most of the encoding settings and allows input via pipe.
Sadly VCEEncC isn't updated that frequently and it doesn't seem like there is a forum or similar to get in touch with the author to get some updates,...

[Roph]

Perhaps the included tools in the AMF SDK can allow you to do that.

HEVC encoding is "officially" released now with the ReLive tool, though the AMF SDK on github hasn't been updated yet to expose it to developers.

[Selur]

From what I gathered so far the problem is that the AMF SDK atm. doesn't have any documentation of the H.265 encoding and one would probably have to check the Media SDK (MFT SDK) which might give some hints,... which Xaymar did and thus could add support for HEVC encoding to OBS ( obs-studio_amf-encoder-plugin/Include/amd-amf-vce.h is probably the most important part when looking into it, to not have to do the exploratory work Xaymar did again)
-> it's a shame AMD didn't add any proper examples or documentation to their AMF SDK. (wild guess is that the amf will probably get an update once the next en-/decoder chip iteration will be added,... -> which might take a while)

[Roph]

Because HEVC encoding isn't "official" yet, neither is it through MFT (which is deprecated). If you look at the AMF issues you can see an AMD employee noting they missed a bug for the ReLive driver release, the SDK should be updated for HEVC with the next hotfix.