HEVC hardware decoding on iMac 27" late 2015

[Sirmausalot]

Just tried an Adobe encode from 4K to H265 to check quality, encoding times, and playback. Unfortunately, haven't had a chance for a full apples to apples comparison keeping bit rate the same etc. But similar. For a 45 minute project, encode times seemed to jump significantly (about 2X) and the H264 file was 4.5GB and the H265 2.5GB. Quality seems to be slightly better on the h264 -- slightly sharper. Playback in H265 is fine and dandy through VLC. I think we are a couple years out from seeing this adopted widely for 4K delivery.

 

[joema2]

Just tried an Adobe encode from 4K to H265..For a 45 minute project, encode times seemed to jump significantly (about 2X) and the H264 file was 4.5GB and the H265 2.5GB. Quality seems to be slightly better on the h264 -- slightly sharper. Playback in H265 is fine and dandy through VLC...

Thanks for testing this. What kind of computer and video card are you using? What was the original 4k codec you used?

 

[Sirmausalot]

i7 iMac 5K with the 395X. We shot 4K Pro Res HQ from a Blackmagic. (Though a few B roll shots in H264 from a GH4). LUT applied to the whole thing and the H264 had an additional bleach bypass effect added while doing an output via Media Encoder (I just wanted to try it and I like it!).

Unfortunately, although some of the bugs were fixed with this premiere pro update, the LUT applied on the timeline is now causing dropped frames during playback at full resolution. Makes me want to try FCPX....

 

[joema2]

...Unfortunately, although some of the bugs were fixed with this premiere pro update, the LUT applied on the timeline is now causing dropped frames during playback at full resolution. Makes me want to try FCPX....

I am testing both Premiere CC and FCP X on various platforms since we have an editor still on CS6 and it doesn't handle H264 4k that well. She will probably end up going to FCP X. In general FCP X is a lot faster than Premiere in terms of playback responsiveness on H264 4k but it currently has no H265 support at all.

However, Premiere is an excellent product and it would be a big step to change editors, esp since FCP X is so different. If you have a big experience base invested in Premiere and benefit from the entire suite I would tend to stay put.

I don't know what Adobe's plans are for hardware accelerated H265 encode/decode. The recent update apparently supports this on specific nVidia GPUs which have NVENC, but probably not via Quick Sync on Skylake CPUs, nor VCE on AMD GPUs. It is an issue since H265 is so compute-intensive.

I have the same iMac as you and I tried several 4k H265 clips from an NX1. VLC would play back some smoothly but not others. It probably depends on the bitrate, frame rate, compression, etc.

 

[otomo]

just finished downloading "Men in Black" in 4K UHD HEVC H.265 (121.8 GB!!!).
it seems impossible to play this on the iMac Late 2015 4.0 GHz. VLC decodes a few
frames but that's it...

So how much money do you have to throw at Apple to play this thing? Will a Mac Pro do it? Is there something in the 2016 release pipeline that will do it? Will it play better in Windows 10 Boot Camp than in OS X on the same hardware?

I understand at $219 Android box can play HEVC 4K content -- http://www.kdlinks.com/index.php/ho...bmc-kodi-support-h-265-hardware-decoding.html

 

[EnesM]

So how much money do you have to throw at Apple to play this thing? Will a Mac Pro do it? Is there something in the 2016 release pipeline that will do it? Will it play better in Windows 10 Boot Camp than in OS X on the same hardware?

I understand at $219 Android box can play HEVC 4K content -- http://www.kdlinks.com/index.php/ho...bmc-kodi-support-h-265-hardware-decoding.html

Something's wrong with that late 2015 iMac not playing it. I have one and plays all 4K content flawlessly, HEVC and H.264

 

[joema2]

So how much money do you have to throw at Apple to play this thing? Will a Mac Pro do it? Is there something in the 2016 release pipeline that will do it? Will it play better in Windows 10 Boot Camp than in OS X on the same hardware?

I understand at $219 Android box can play HEVC 4K content -- http://www.kdlinks.com/index.php/ho...bmc-kodi-support-h-265-hardware-decoding.html

H265 (HEVC) is a brand-new computationally-intensive video codec. It generally requires some kind of hardware acceleration to decode smoothly. Intel's Quick Sync on Skylake and later CPUs have this feature, as do a few high-end nVidia and AMD GPUs. Those APIs are called NVENC and VCE. Even if the hardware is present, the software (video player, video editor, etc) must write to those APIs to use them. E.g, FCPX uses Quick Sync for H264 encoding but Premiere CC (as of now) does not. FCPX does not yet use Quick Sync for H265. Premiere does use NVENC if you have those few GPU cards which support that.

There are numerous issues with H265 regarding intellectual property and licensing which will likely slow the deployment. It is possible that these will take several years to resolve, by which time hardware encode/decode support will be more widespread. If there are too many problems with H265, the competing royalty-free VP9 codec (backed by Google) could instead dominate.

I have done a few tests of H265 playback on my 2015 top-spec iMac 27 and it can be very sluggish. OTOH Premiere CC seems to handle it fairly well -- actually better than H264 -- which implies they have an optimized code path for that or are somehow using the Skylake hardware encoder.

The Android KDLinks A300 box is a set-top-box designed for video playback. It is a low-cost item with limited functionality which emphasizes quick "time to market". Some of the newer ARM CPUs or SoCs have H265/HEVC built in and are embedded in some new smart TVs. On AVSForum you can see some people trying to use the A300 box for 4k playback -- some have success; some do not. So there is a difference between what is advertised vs how well it works.

If you have a Mac with a Skylake CPU (in general 2015 or later) its CPU can probably handle H265/HEVC decoding -- from a hardware standpoint. Whether the software does is up to the software vendor. If you are playing back via VLC that is an issue for VLC to answer, not Apple. I haven't tested whether QuickTime Player has H265/HEVC support but I would tend to doubt it since the codec is so new.

 

[yellowscreen]

H265 (HEVC) is a brand-new computationally-intensive video codec. It generally requires some kind of hardware acceleration to decode smoothly. Intel's Quick Sync on Skylake and later CPUs have this feature, as do a few high-end nVidia and AMD GPUs. Those APIs are called NVENC and VCE. Even if the hardware is present, the software (video player, video editor, etc) must write to those APIs to use them. E.g, FCPX uses Quick Sync for H264 encoding but Premiere CC (as of now) does not. FCPX does not yet use Quick Sync for H265. Premiere does use NVENC if you have those few GPU cards which support that.

There are numerous issues with H265 regarding intellectual property and licensing which will likely slow the deployment. It is possible that these will take several years to resolve, by which time hardware encode/decode support will be more widespread. If there are too many problems with H265, the competing royalty-free VP9 codec (backed by Google) could instead dominate.

I have done a few tests of H265 playback on my 2015 top-spec iMac 27 and it can be very sluggish. OTOH Premiere CC seems to handle it fairly well -- actually better than H264 -- which implies they have an optimized code path for that or are somehow using the Skylake hardware encoder.

The Android KDLinks A300 box is a set-top-box designed for video playback. It is a low-cost item with limited functionality which emphasizes quick "time to market". Some of the newer ARM CPUs or SoCs have H265/HEVC built in and are embedded in some new smart TVs. On AVSForum you can see some people trying to use the A300 box for 4k playback -- some have success; some do not. So there is a difference between what is advertised vs how well it works.

If you have a Mac with a Skylake CPU (in general 2015 or later) its CPU can probably handle H265/HEVC decoding -- from a hardware standpoint. Whether the software does is up to the software vendor. If you are playing back via VLC that is an issue for VLC to answer, not Apple. I haven't tested whether QuickTime Player has H265/HEVC support but I would tend to doubt it since the codec is so new.

Why do you keep saying its new?

Its not new, ive been waiting for it for years. Double the quality with the same bitrate. They better hurry with those 4k movies. Its moving too slow. I feel like congress suddenly took control of the movie production industry an has to reach a wider social compromise, whats the holdup?

I mean, same quality half the bitrate? This should be mandated by law.

Apple used h265 for facetime in iphone 6. Since then all mentions of h265 just vanished over night. Probably those legal issues. Buy it then cheap ****ers with 250BBB IN THE BANK JESUS.

 

[joema2]

Why do you keep saying its new?

Its not new, ive been waiting for it for years. Double the quality with the same bitrate. They better hurry with those 4k movies. Its moving too slow....whats the holdup?...

HEVC/H.265 version 2 was only published last year. HEVC in general takes 10x the CPU power to encode and 2x the CPU power to decode as H.264 at the same bit rate and resolution. For 4k playback this would be 8x the CPU power to decode relative to H.264 1080p. It generally requires specific hardware to decode with good performance which in the Intel CPU family means Skylake or later. To my knowledge the only video camera which used H.265 was the Samsung NX1 which was cancelled.

Besides technical issues it may never achieve wide adoption due to licensing disputes:

http://www.cnet.com/news/patent-group-raises-new-fees-uncertainty-for-4k-video/

http://arstechnica.com/tech-policy/...-threatens-to-derail-4k-hevc-video-streaming/

Also there are various other issues impeding a wide deployment:

http://www.streamingmedia.com/Artic....265-and-VP9-Adoption-Not-So-Fast-104430.aspx