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Im 100 percent certain the app does not do HDR. If it did it would show up in quality settings like on the iPhone. 4k60 still looks amazing on my oled.
Does it airplay at 4K 60 finally? Does it allow you to select it on the phone while air playing?
 
So basically Youtube is not supporting range matching. There are 3 scenarios:


1. If you have your Apple TV set to SDR and load a HDR video in Youtube it will stay in SDR mode.

2. If you have your Apple TV set to HDR and load a HDR video in Youtube it will stay in HDR mode.

3. If you have your Apple TV set to Dolby Vision and load a HDR video in Youtube it will stay in Dolby Vision mode.



So the question is if you manually select HDR mode as in Scenario 2 is Youtube actually outputting real HDR from the video? (Good luck trying to explain this to Apple or Youtube)
 
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BT.2020 does not automatically mean HDR playback:


No but "SMPTE 2084 PQ" does.

smpte2084 does though doesn’t it?
Correct

Im 100 percent certain the app does not do HDR. If it did it would show up in quality settings like on the iPhone.

That's not a reliable indication. The Youtube app on my TV 100% supports HDR but it doesn't say HDR in the quality settings either.

What we need is for someone to do some real measurements and analysis to see if the HDR is real or fake.
 
No but "SMPTE 2084 PQ" does.


Correct



That's not a reliable indication. The Youtube app on my TV 100% supports HDR but it doesn't say HDR in the quality settings either.

What we need is for someone to do some real measurements and analysis to see if the HDR is real or fake.
Who knows. I tried the famous HDR videos on both SDR and HDR settings for the ATV and both look great. id probably need a direct AB comparison to see a difference. I prefer to keep my tv in SDR as I dont like the fake HDR and I already ruined one panel by leaving it in HDR all the time. I mainly watch non HDR content such as Sling. I hope YouTube updates their app too. They did for the 4k60 stuff.
 
The two screenshots are hilarious to me, I cannot verify the information shown since I do not have one but the one done with the ATV 4K 2017 shows that YT is not even sending an UHD ("4k") video file to the ATV to output - maybe an Apple SoC performance issue when having to decode VP9 in software*?

Again, I don't understand how this hasn't lead to a public "sh**storm" considerung what stupid things in the past actually did.

*I'm also pissed about the outdated A12 SoC in the ATV 4K 2021, not because of gaming stuff (not my cup of tea) but to have room for future features like maybe being able to decode UHD-HDR AV1 in software which is an intermediate destination coming pretty soon.



It seems the ATV 4K 2017 isn't even able to decode 4K YouTube video files in real-time due to Google's video codec or Apple's SoC video codec feature set choice. The 2021 model on the other hand can at least do that so I guess you'll have to wait till 2025 to get HDR! 🤣
Yeah it seems it’s only videos that are 4K HDR @60hz that the ATV4K 2017 has an issue with so drops down to 2560x1440@60.

If it’s 4K HDR @24hz then it plays back at 3840x2160@24 and just drops the HDR.
Not that the frame rate makes much difference anyway as currently the YouTube app doesn’t support frame rate matching so even though stats for nerds says it @24 the TV just displays it at whatever you have the ATV4K set to which will usually be wither @50hz or @60hz.
 
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No but "SMPTE 2084 PQ" does.


Correct



That's not a reliable indication. The Youtube app on my TV 100% supports HDR but it doesn't say HDR in the quality settings either.

What we need is for someone to do some real measurements and analysis to see if the HDR is real or fake.
People, please start thinking a bit critically and do testing to verify your "ideas".

Here is a photo with the YT app and tvOS 14.6 on an ATV 4K 2021. The GUI is set to 4K SDR with full-range RGB output.

Dynamic range matching is enabled but since the YT app doesn't support it it doesn't matter - note your "SMPTE 2084 PQ evidence". Just because a video file is proper HDR doesn't mean the player software (YT app) is decoding and sending it out properly. The only "HDR" you are currently seeing with the YT app is fake HDR applied after the fact by the ATV GUI software that has nothing to do with the original HDR content!
 

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People, please start thinking a bit critically and do testing to verify your "ideas".

Here is a photo with the YT app and tvOS 14.6 on an ATV 4K 2021. The GUI is set to 4K SDR with full-range RGB output.

Dynamic range matching is enabled but since the YT app doesn't support it it doesn't matter - note your "SMPTE 2084 PQ evidence". Just because a video file is proper HDR doesn't mean the player software (YT app) is decoding and sending it out properly. The only "HDR" you are currently seeing with the YT app is fake HDR applied after the fact by the ATV GUI software that has nothing to do with the original HDR content!
What does the freesync info show if HDR was actually working?
 
What does the freesync info show if HDR was actually working?
It shows and proves the exact opposite.

- Some people seem to think that just because the YouTube app lists "SMPTE 2084 PQ" in its details that they are getting real HDR;

- The RGB in the FreeSync details proves that the ATV itself is only outputting an SDR signal since currently it cannot output HDR with RGB, even then the YT app is showing its little SMPTE 2084 PQ note;

- The ATV GUI is sitting on top of everything and applys its "HDR" (cranking up colors and brightness "by chance") to anything if its HDMI output is set to 4K HDR;
 
It shows and proves the exact opposite.

- Some people seem to think that just because the YouTube app lists "SMPTE 2084 PQ" in its details that they are getting real HDR;

- The RGB in the FreeSync details proves that the ATV itself is only outputting an SDR signal since currently it cannot output HDR with RGB, even then the YT app is showing its little SMPTE 2084 PQ note;

- The ATV GUI is sitting on top of everything and applys its "HDR" (cranking up colors and brightness "by chance") to anything if its HDMI output is set to 4K HDR;
I only asked because I don't think I have seen my AppleTV show RGB under freesync on my CX it has always show YCbCr.
 
I only asked because I don't think I have seen my AppleTV show RGB under freesync on my CX it has always show YCbCr.
That is strange:

If I set the output format to "4K SDR", I can choose between "YCbCr", "RGB High" and "RGB Low" in the HDMI Output options below the "Format" menu.

If set to "4K HDR" this is no longer possible and YCbCr 4:2:2 is the "best" there is since Apple understandably doesn't have the software engineering resources to implement the HDMI 2.1 standard properly for an "innovative" new product at launch.
 
You need a faster cable. I got a fast one 4 years ago and it handles dolby vision and all the highest settings.

UCB right?”That is strange:

If I set the output format to "4K SDR", I can choose between "YCbCr", "RGB High" and "RGB Low" in the HDMI Output options below the "Format" menu.

If set to "4K HDR" this is no longer possible and YCbCr 4:2:2 is the "best" there is since Apple understandably doesn't have the software engineering resources to implement the HDMI 2.1 standard properly for an "innovative" new product at launch.
 
@richard371

?

(I only use HDMI cables that can handle 48 Gbit/s, the bestest standard there currently is for HDMI 2.1)

But even worse cables shouldn't do much to the ATV 4K 2021 with its current firmware since it is not actually using HDMI 2.1 video output.
 
If you actually read my entire post you'll know that's exactly what I did.
I am unable to follow your logic.

You at first interjected that my statement regarding "SMPTE 2084 PQ" NOT automatically meaning HDR playback was incorrect.

This comes after multiple users including me were able to determine with their eyeballs that the tvOS YT app is not showing real HDR but it is only using the fake HDR applied over everything by the ATV GUI.

I then supported this subjective opinion with objective evidence showing HDMI link status details where even if the TV is guaranteed to not get an HDR HDMI signal due to the ATV's current firmware limitations when using the RGB color space, the tvOS YT app is still showing "SMPTE 2084 PQ".

If you disagree with this point of view then you should form a coherent argument outlining what's wrong with the one I presented instead of pumping out vague one-liners. Then I would constructively engage further.

But at this point in time I personally think that people that state that HDR is actually working correctly with the current tvOS YT app have the burden of proof.
 
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I am unable to follow your logic.

You at first interjected that my statement regarding "SMPTE 2084 PQ" NOT automatically meaning HDR playback was incorrect.
That is not at all what you said. This is what you said: "BT.2020 does not automatically mean HDR playback:"

"SMPTE 2084 PQ" does indeed mean that Youtube is playing an HDR source video.
This comes after multiple users including me were able to determine with their eyeballs that the tvOS YT app is not showing real HDR but it is only using the fake HDR applied over everything by the ATV GUI.
Eyeballs are not a scientific measurement.
I then supported this subjective opinion with objective evidence showing HDMI link status details where even if the TV is guaranteed to not get an HDR HDMI signal due to the ATV's current firmware limitations when using the RGB color space, the tvOS YT app is still showing "SMPTE 2084 PQ".
Completely irrelevant. When the AppleTV is in HDR mode the Youtube app also says SMPTE 2084 PQ. So does that mean we've just proven it plays HDR?
If you disagree with this point of view then you should form a coherent argument outlining what's wrong with the one I presented instead of pumping out vague one-liners. Then I would constructively engage further.

But at this point in time I personally think that people that state that HDR is actually working correctly with the current tvOS YT app have the burden of proof.
There is no need to form "arguments". Again what we need is someone to use measuring tools to do a scientific comparison.

Until then all your arguments and proclamations are meaningless.
 
So does that mean we've just proven it plays HDR?
No.

You - again - showed that Google is sending a video file with HDR properties from its servers to the tvOS YT app. It says nothing about the tvOS YT app actually decoding this file properly and generating a video signal that also includes the HDR information from the original video file for the ATV to output via HDMI.

Now we're back to posting #13:

The crux is HDR playback (output). I can watch an HDR video file on my old 2012 MBP but just because the file itself is okay doesn't mean the player can output that if other links in the viewing chain "kill" the HDR transmission.

"De-HDRing" a real HDR file and than applying some sort of "HDR" after the fact by the Apple TV GUI that can itself run and output in HDR doesn't have much to do with real HDR.

I hope I'm not coming off too mean, I'm still mad about my personal viewing disappointment with the Apple TV 4K 2021 in its current state.


It shows and proves the exact opposite.

- Some people seem to think that just because the YouTube app lists "SMPTE 2084 PQ" in its details that they are getting real HDR;

- The RGB in the FreeSync details proves that the ATV itself is only outputting an SDR signal since currently it cannot output HDR with RGB, even then the YT app is showing its little SMPTE 2084 PQ note;

- The ATV GUI is sitting on top of everything and applys its "HDR" (cranking up colors and brightness "by chance") to anything if its HDMI output is set to 4K HDR;
 
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No.

You - again - showed that Google is sending a video file with HDR properties from its servers to the tvOS YT app. It says nothing about the tvOS YT app actually decoding this file properly and generating a video signal that also includes the HDR information from the original video file for the ATV to output via HDMI.
Correct.

- The RGB in the FreeSync details proves that the ATV itself is only outputting an SDR signal since currently it cannot output HDR with RGB, even then the YT app is showing its little SMPTE 2084 PQ note;

- The ATV GUI is sitting on top of everything and applys its "HDR" (cranking up colors and brightness "by chance") to anything if its HDMI output is set to 4K HDR;

This is nothing but an assumption on your part. Once again without measurements there is no way to prove whether the AppleTV is applying "fake" HDR on top of a SDR video from youtube, or whether it is passing the HDR video thru.

And I don't want to add to the assumptions but it would seem silly to have a HDR file be stripped of HDR and then add fake HDR on top of it. It would be much easier to just play the original HDR file as is. But we've seen lots of silly things from AppleTV so again I don't want to make assumptions. I'll wait until someone has definitive proof.
 
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If you cannot accept an LG status display showing an HDMI input signal not being HDR since the ATV cannot even output an RGB HDR signal at all (!) then I honestly think that you are just trolling and I fell for it.
 
If you cannot accept an LG status display showing an HDMI input signal not being HDR since the ATV cannot even output an RGB HDR signal at all (!) then I honestly think that you are just trolling and I fell for it.
Why are you outputting SDR? Are you aware that you need to set your AppleTV to HDR for this conversation to even make any sense?

Are you aware that your LG shows a popup anytime it detects HDR? Why are you even looking at a secret menu?

One thing we know for sure is that Youtube does not support format matching.

Seems like I'm the one being trolled.
 
So if YouTube in tvOS doesn’t support hdr then kindly tell me what’s the point of the bloody £169 premium of Apple TV?! My web OS YouTube app plays HDR just fine. This is ridiculous.

In addition there’s the recommendation to run the sole tv in 4K HDR with content matching. If we do this then the beautiful screensavers are muted in SDR - the same screensavers we are told it’s worth upgrading to the 64GB model for.
The entire platform is an absolute mess and it’s about time somebody called it out.
If all you or anyone watches is YouTube then you answered your own question.
 
Has anyone used streaming stats in developer settings to see if what dynamic range is being decoded internally for youtube hdr vids?

Someone on reddit was able to use this to determine 4K titles on HBO Max have been downscaled to 2K SDR on the latest update.


 
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