ATV HDR transmission

michial

macrumors 6502a
Original poster
Sep 15, 2009
601
242
Just bought a 4KATV and pairing it with an OledC9 I notice it always transmits as though it were broadcasting HDR even when it is not. I have my settings at 4K HDR 60 with 4:2:2 as is the correct representation with my TV capabilities. However, it’s error of always transmitting HDR when it isn’t actually HDR causes every menu to be dimmed. Is there a fix for this?
 

musicman0725

macrumors regular
Oct 25, 2007
111
6
Just bought a 4KATV and pairing it with an OledC9 I notice it always transmits as though it were broadcasting HDR even when it is not. I have my settings at 4K HDR 60 with 4:2:2 as is the correct representation with my TV capabilities. However, it’s error of always transmitting HDR when it isn’t actually HDR causes every menu to be dimmed. Is there a fix for this?
Yes, you will want to go to the video settings and change the output to 4K SDR 60 (4:4:4). Then go to match content and turn on match range and match frame rate.
 
  • Like
Reactions: Wolfpup

michial

macrumors 6502a
Original poster
Sep 15, 2009
601
242
Yes, you will want to go to the video settings and change the output to 4K SDR 60 (4:4:4). Then go to match content and turn on match range and match frame rate.
It defaulted to 4:2:0 so I changed to 4:2:2. This is odd as every other device hooked up is 4:2:2 not 4:4:4. Is Apple planning on fixing this as it seems like a jerry fix that shouldn’t need fixing on a $200 streaming device.
 

musicman0725

macrumors regular
Oct 25, 2007
111
6
It defaulted to 4:2:0 so I changed to 4:2:2. This is odd as every other device hooked up is 4:2:2 not 4:4:4. Is Apple planning on fixing this as it seems like a jerry fix that shouldn’t need fixing on a $200 streaming device.
Honestly doesn’t matter what you have chroma set to as it only applies to the menus. 4:2:2 is the max chroma for HDR, 4:4:4 is the max for SDR. Main thing is to enable match range and frame rate. This will auto-switch to HDR when the app and content support it. Reason to switch menu output to 4K SDR is that some apps don’t properly set the flag so if you have match range enabled and your menu output is set to 4K HDR, the app won’t switch to SDR even when they have no HDR content. Match frame rate is important too because even if you have a lower chroma set at 60p for the menus, when it matches to a lower frame rate like 24p for most movie content, it will be able to automatically step up to a higher chroma due to the lower bandwidth usage. Features such as Dolby Vision on some TVs depend on this setting because they don’t support DV above 30 fps. One other thing is you’ll want to make sure hdmi 2.0 full bandwidth is enabled on your TV (HDMI Ultra HD Deep Color). If you are doing through a receive you’ll also want to make sure HDMI enhanced mode is enabled (which is the same thing as HDMI Ultra HD Deep Color but receivers don’t call it that). If you have issues enabling HDMI 2.0 high bandwidth, make sure you are using an HDMI Premium Certified cable. The monoprice ones on Amazon are cheap and work well.
 
  • Like
Reactions: Wolfpup

Wolfpup

macrumors 68030
Sep 7, 2006
2,766
74
I’m so glad you guys can explain this, but it’s soooo confusing and I’m more literate about it than most, and still kind of confused. For crying out loud, just output 4K sdr for menus (even if they’re rendered below that to save ram) and have programs switch to hdr and whatnot as needed. That should be the default 😕

I’ll probably have to ask you guys once I actually have an Apple TV and have it set up, to make sure I did it right.
 

priitv8

macrumors 68040
Jan 13, 2011
3,621
467
Estonia
That should be the default 😕
I think Apple's thinking was that the screen blackout that encompasses mode switches (and whose duration is dependent on the particular display), is ruining the fluid user experience. Hence fix HDMI output to single mode by default and try to handle everything (ie necessary tonemapping) in software.
 
  • Like
Reactions: waw74

Ritsuka

macrumors 65816
Sep 3, 2006
1,057
489
Every movie and tv show that is playable on the AppleTV is 4:2:0, so setting 4:2:0 or 4:4:4 will improve color smearing a bit in the normal UI (that is not noticeable anyway on a 4k screen), but makes no difference at all for video playback.
 
  • Like
Reactions: Audit13
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.