HDR Support tvOS 11.2 b1

[barong]

Hi,

I'm currently trialing MrMC and it all looks good except for HDR on my Apple TV 4k running tvOS 11.2 b1 .
I can load the file, but it shows up in black and white only, no colour.

Is there any extra settings I need to set in MrMC or is it a limitation of using tvOS 11.2 b1?
If I can get this sorted I'll be upgrading to the pro/paid version for sure.

Thanks in advance.

EDIT:
I have used the settings as per the screenshot in this post:
https://mrmc.tv/2017/10/19/mrmc-3-2-0-a ... on-ios-11/
The file loads, but doesn't kick the TV into HDR mode and plays in B&W.

[amet]

tvOS 11.2 is beta and there might be issues there... as far as we have tested there are no issues in using HDR on 11, apples beta versions are known to have bugs

[cosmoxl]

yeah, I see people on reddit wanting to remove 11.2 beta from their ATV4k. as far as I know there's no way to do that except to take it into an apple store since it doesn't have the USB-c port anymore.

[Everbrave]

yeah, I see people on reddit wanting to remove 11.2 beta from their ATV4k. as far as I know there's no way to do that except to take it into an apple store since it doesn't have the USB-c port anymore.

Yes, they cannot reinstall tvOS 11.1 but they can Reset the device and reinstall their apps.

Edit: tvOS 11.2 beta 2 has been released

[higher]

HDR works fine for me with 11.2 b2, passthrough audio doesn't but that's another topic.
Make sure you set the ATV 4K to HDR mode because Match Dynamic Range currently works only in iTunes.

While I'm at it, did you guys notice that 4K HDR 60hz sends a 10-bit YCbCr 4:2:0 signal while 4K HDR 24hz sends 8-bit YCbCr 4:2:2? I didn't do a comparison yet with various movies but I think there would be some banding with the 8-bit signal. Why ATV doesn't offer 24hz 10-bit YCbCr 4:2:0 is beyond me since all content is mastered like that.

[cosmoxl]

tvOS 11.2 beta 2 is out now. However, it seems to be failing to install on a lot of devices. On mine it fails so far.

[barong]

Thanks for the updates. I presume this will get changed in a future release to accommodate the refresh rate/DR mode auto switching that is available in tvOS 11.2?
Currently auto HDR switching is working in Netflix and Plex (using a modified profile) as they would be using the inbuilt media player.

[noggin]

While I'm at it, did you guys notice that 4K HDR 60hz sends a 10-bit YCbCr 4:2:0 signal while 4K HDR 24hz sends 8-bit YCbCr 4:2:2? I didn't do a comparison yet with various movies but I think there would be some banding with the 8-bit signal. Why ATV doesn't offer 24hz 10-bit YCbCr 4:2:0 is beyond me since all content is mastered like that.

Could be that the ATV 4K doesn't offer 24Hz 10-bit YCbCr 4:2:0 output because it isn't apparently officially supported by HDMI 2.0 AIUI?.

https://www.hdmi.org/manufacturer/hdmi_ ... q.aspx#146

4:2:2 / 4:4:4 / RGB are the only supported formats for 2160/30p and below frame rates. No 4:2:0 support for <50Hz output on HDMI 2.0. (Though that grid also suggests HDMI 2.0 only supports 2160/24p 4:2:2 at 12 bit, though I'm sure I've seen 4:2:2 8-bit 4K 24p - maybe that is part of the HDMI 1.4 spec?)

4:2:0 output over HDMI is only supported for 2160/50p, 59.94p and 60p frame rates (along with 4:2:2 and even 4:4:4 at some bit depths).

(4:2:0 was partially added to the HDMI spec to allow for 2160/50p and 2160/60p content to be carried in an HDMI 1.4b physical bandwidth link, which is how manufacturers like Sony were able to 'upgrade' their UHD TVs to add 'HDMI 2.0' compatibility with a firmware update. It only added 4:2:0 2160/50p and 60p modes at low bit depths...)

[higher]

Could be that the ATV 4K doesn't offer 24Hz 10-bit YCbCr 4:2:0 output because it isn't apparently officially supported by HDMI 2.0 AIUI?.

https://www.hdmi.org/manufacturer/hdmi_ ... q.aspx#146

4:2:2 / 4:4:4 / RGB are the only supported formats for 2160/30p and below frame rates. No 4:2:0 support for <50Hz output on HDMI 2.0. (Though that grid also suggests HDMI 2.0 only supports 2160/24p 4:2:2 at 12 bit, though I'm sure I've seen 4:2:2 8-bit 4K 24p - maybe that is part of the HDMI 1.4 spec?)

4:2:0 output over HDMI is only supported for 2160/50p, 59.94p and 60p frame rates (along with 4:2:2 and even 4:4:4 at some bit depths).

(4:2:0 was partially added to the HDMI spec to allow for 2160/50p and 2160/60p content to be carried in an HDMI 1.4b physical bandwidth link, which is how manufacturers like Sony were able to 'upgrade' their UHD TVs to add 'HDMI 2.0' compatibility with a firmware update. It only added 4:2:0 2160/50p and 60p modes at low bit depths...)

Yes you are right, I didn't think about the specs. So that's why my gtx 1080ti sends RGB/12-bit/24hz when HDR is enabled from the Windows settings. ATV 4K could do this as well and I'd be more than satisfied.