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iMac Pro Will the Next Regular iMac beat the Current iMac Pro Base Model?

seasurfer said:
Can the iMac Pro do it?
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The iMac Pro can *decode* 10-bit 4k HEVC, apparently using AMD's UVD hardware-accelerated decoding -- IF playing that video file in Quicktime Player. Whether VLC or any other player will use hardware accelerated HEVC decoding depends on whether that app calls the APIs to access AMD's UVD hardware: https://en.wikipedia.org/wiki/Unified_Video_Decoder

But Netflix is streaming playback not file-based. Netflix 4k is encoded using 10-bit 4k HEVC. However due to copy protection issues only specific client types can play Netflix 4k -- certain TVs, certain set-top boxes, etc. The only computer operating system currently supported is Windows 10 and the Edge browser.

In theory the iMac Pro could play that if running Windows via Bootcamp, Parallels Desktop or VMWare Fusion, and assuming the Edge browser is written to use AMD's UVD, not just Quick Sync.

In actuality I think that's unlikely. There would be a greater chance a 2017 iMac 27 would work for this, but that's unknown until somebody actually tests it running Windows and using the Edge browser.

Hopefully Apple will eventually support this in Safari on macOS, which would enable streaming Netflix 4k on iMacs running Kaby Lake or later CPUs or on iMac Pros.
 
joema2 said:
The iMac Pro can *decode* 10-bit 4k HEVC, apparently using AMD's UVD hardware-accelerated decoding -- IF playing that video file in Quicktime Player. Whether VLC or any other player will use hardware accelerated HEVC decoding depends on whether that app calls the APIs to access AMD's UVD hardware: https://en.wikipedia.org/wiki/Unified_Video_Decoder
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I can decode 10-bit 4K HEVC on my MacBook Core m3 Kaby Lake with QuickTime too. With one 76 Mbps 10-bit 2160p 60 fps HEVC demo file from Sony I tried, CPU usage was about 25%, and playback was completely smooth.

https://forums.macrumors.com/threads/4k-hevc-10-bit-on-the-2017-core-m3-macbook-is-gorgeous.2054232/

IINA also works. vlc has also incorporated hardware acceleration for 4K HEVC playback but it still kinda sucks in vlc.
 
EugW said:
...This would work with Boot Camp, but I wasn't aware it would also work with VMware or Parallels. Has that been confirmed?...
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The previous article I cited said it would work in Parallels or VMWare, but I haven't tried it myself. If it worked it would almost certainly only be on a 2017 iMac not an iMac Pro, because I seriously doubt Microsoft's Edge is making AMD UVD API calls, rather it's probably just using Quick Sync.
 
joema2 said:
The previous article I cited said it would work in Parallels or VMWare, but I haven't tried it myself. If it worked it would almost certainly only be on a 2017 iMac not an iMac Pro, because I seriously doubt Microsoft's Edge is making AMD UVD API calls, rather it's probably just using Quick Sync.
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I just read the comments, and one commenter on that article said he tried it in Parallels and it didn't work.

BTW, Netflix 4K is supposed to work on AMD Polaris and Vega starting 2018 Q2. Ryzen 2200g and 2400g will also be supported. It will be through both the Edge browser or else the dedicated Win 10 Netflix application.

On the nVidia side it's 1050 or higher with 3 GB, which irritated me to no end, because all the 1050 cards available are dual-slot full-height cards. My primary Windows 10 machine is a slim Phenom 6-core 1055T machine that can only accomodate up to a 1030 low profile single-slot lower power card. I'm hoping Vega will introduce an inexpensive low profile single-slot lowish power card that will solve this problem.
 
EugW said:
...vlc has also incorporated hardware acceleration for 4K HEVC playback but it still kinda sucks in vlc.
Click to expand...

There are three types of H264 or HEVC hardware acceleration: (1) Quick Sync which is in Intel CPUs starting with Sandy Bridge (10-bit HEVC starting with Kaby Lake, 8-bit HEVC starting with Skylake), (2) AMD's UVD, (3) nVidia's NVDEC.

Quick Sync, UVD and NVDEC are all fixed-function specialized hardware separate from the GPU. They each have unique APIs, programming requirements and software frameworks to access them. Each has multiple versions which support various video parameters. Using nVidia for example, the support matrix is very complicated, and they are all three like this: https://developer.nvidia.com/video-encode-decode-gpu-support-matrix

So the hardware itself must be present, it must be the right version to support your desired video stream, the OS must support it, and the app layer must support it. If any of those isn't "on board" it won't work or will fall back to software-only decoding.

E.g, if Windows VLC supports Quick Sync hardware-accelerated HEVC that doesn't mean the Mac version does. If the Mac version of VLC supports it on iMac (via Quick Sync) that doesn't mean VLC supports it on the iMac Pro using UVD, or on an older-generation Mac Pro with an nVidia GPU. The app (VLC in this case) would have to call three different decoding APIs to function on those three different Mac platforms.

With HEVC a good example of this hardware/software performance difference is FCPX 10.4 encoding 4k HEVC on an iMac Pro. 8-bit encoding is hardware accelerated, 10-bit encoding is not, and is 32 times slower.
 
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joema2 said:
There are three types of H264 or HEVC hardware acceleration: (1) Quick Sync which is in Intel CPUs starting with Sandy Bridge (10-bit HEVC starting with Kaby Lake, 8-bit HEVC starting with Skylake), (2) AMD's UVD, (3) nVidia's NVDEC.

Quick Sync, UVD and NVDEC are all fixed-function specialized hardware separate from the GPU. They each have unique APIs, programming requirements and software frameworks to access them. Each has multiple versions which support various video parameters. Using nVidia for example, the support matrix is very complicated, and they are all three like this: https://developer.nvidia.com/video-encode-decode-gpu-support-matrix

So the hardware itself must be present, it must be the right version to support your desired video stream, the OS must support it, and the app layer must support it. If any of those isn't "on board" it won't work or will fall back to software-only decoding.

E.g, if Windows VLC supports Quick Sync hardware-accelerated HEVC that doesn't mean the Mac version does. If the Mac version of VLC supports it on iMac (via Quick Sync) that doesn't mean VLC supports it on the iMac Pro using UVD, or on an older-generation Mac Pro with an nVidia GPU. The app (VLC in this case) would have to call three different decoding APIs to function on those three different Mac platforms.

With HEVC a good example of this hardware/software performance difference is FCPX 10.4 encoding 4k HEVC on an iMac Pro. 8-bit encoding is hardware accelerated, 10-bit encoding is not, and is 32 times slower.
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I was just saying that third party software does indeed support hardware 10-bit HEVC decode on the Mac already. It's not just QuickTime. IINA supports Quick Sync for 10-bit 4K HEVC decode as does vlc, but while it works well in IINA, it doesn't in vlc. Yes, we've already tried it.

However, I don't know if Vega is supported because I don't know if anyone has tested it yet in IINA. (I haven't been reading much of the iMac Pro threads and the ones I have read didn't mention anything about it.) Furthermore, I'm not sure there if there is much point in testing it in vlc right now, because vlc's implementation has been poor from all accounts so far, at least on other hardware, Intel or otherwise. But then again, it might be worth a shot. Perhaps vlc does support AMD on the Mac now and vlc's implementation of hardware acceleration of HEVC on AMD is better than their implementation for hardware acceleration of HEVC on Intel. BTW, the other reason why people may not have tested this much is because the latest 3.0 update for vlc only landed this month. I'd suggest trying IINA first though, or at least at the same time as vlc.
 
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EugW said:
I just read the comments, and one commenter on that article said he tried it in Parallels and it didn't work.

BTW, Netflix 4K is supposed to work on AMD Polaris and Vega starting 2018 Q2. Ryzen 2200g and 2400g will also be supported. It will be through both the Edge browser or else the dedicated Win 10 Netflix application.

On the nVidia side it's 1050 or higher with 3 GB, which irritated me to no end, because all the 1050 cards available are dual-slot full-height cards. My primary Windows 10 machine is a slim Phenom 6-core 1055T machine that can only accomodate up to a 1030 low profile single-slot lower power card. I'm hoping Vega will introduce an inexpensive low profile single-slot lowish power card that will solve this problem.
Click to expand...


The other guy mentions you need an Intel GPU. Ugh....this is painful with the lack of 4k movie/show content on these iMacs.


satoristeph


After much research, I have come to the conclusion that watching 4k in Netflix in bootcamp on an Apple machine is only possible if one if using Intel GPU. If one is using any flavor of Radeon, the DRM necessary (PlayReady 3) is not available in any driver and so it will not work. An external GPU running a Nvidia card MAY be possible as they have drivers that include the DRM.

Fri Jan 5, 2018 5:48am
 
fathergll said:
The other guy mentions you need an Intel GPU. Ugh....this is painful with the lack of 4k movie/show content on these iMacs.


satoristeph


After much research, I have come to the conclusion that watching 4k in Netflix in bootcamp on an Apple machine is only possible if one if using Intel GPU. If one is using any flavor of Radeon, the DRM necessary (PlayReady 3) is not available in any driver and so it will not work. An external GPU running a Nvidia card MAY be possible as they have drivers that include the DRM.

Fri Jan 5, 2018 5:48am
Click to expand...
This is well known actually. The only GPUs supported for Netflix 4K (on Windows) are:

Intel Kaby Lake 7th generation
NVIDIA GeForce 1050 or higher, with at least 3 GB RAM

As of March 2018, no AMD GPUs are supported. That will change in Q2 2018 however. Some Polaris GPUs will be supported, but again that leaves out anything below the 2017 model iMacs because the 2015 and earlier do not have Polaris, which came out mid 2016. Interestingly though, some of the 2016 MacBook Pros have Polaris.

Note also, this appears to be is Boot Camp only. No mention of virtual machine support.

---

I am still hopeful that macOS 10.14 will introduce Netflix 4K streaming support, but I believe even if it does come to macOS, it will only support the 2017 MacBooks, 2017 iMacs, 2017 iMac Pro, and 2017 MacBook Pros. Although the support for the iMac Pro would be via its AMD GPU, that AMD GPU support would not extend to the Polaris MacBook Pros. I suspect for marketing reasons, Apple would make Vega in the iMac Pro the hard cutoff, and will not extend the support to Polaris on the Mac. Also, the 2017 MacBook Airs would not be supported, since they are using 5th generation Broadwell.
 
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I don't understand, we can easily stream 4K video on Youtube, why not Netflix?
 
seasurfer said:
I don't understand, we can easily stream 4K video on Youtube, why not Netflix?
Click to expand...
YouTube:
4K SDR VP9 video, no DRM (Some may be HDR though.)

Netflix 4K:
4K HDR HEVC video, with DRM (Some may be SDR though.)

HEVC is much, much harder to decode than VP9, and HDR HEVC is even harder to decode. And Netflix has digital rights management. If your hardware and software are not compliant, then you get no video at all.
 
Mac32 said:
Best possible scenario IMO is a new iMac design with upgraded thermal system. If a new iMac design were only a few months away, wouldn't there be some rumours by now?.
Click to expand...

I expect a new chassis for one simple reason, 20th anniversary
 
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