Apple TV 4K doesn't support 24Hz output (Correction - it does now)

Discussion in 'Apple TV and Home Theater' started by ActionableMango, Sep 14, 2017.

  1. andrewstirling macrumors 6502

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    May 19, 2015
    #276
    I get that you would prefer your tv to do the upscaling....I would to. But I actually think the Apple TV is decent at upscaling so it’s not that big a deal to me. And I’m someone who gave up on the shield TV because of its poor upscaling and inability to switch resolution.
     
  2. benji888 macrumors 68000

    benji888

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    United States
    #277
    Apparently. ...on a similar note, while iPhone 8 & X, 2017 iPad Pros play HDR10 & DV video, older devices with the same panels won’t do it...the 8 has exactly the same screen as the 7...it seems only A11 or A10X devices have the needed hardware.
     
  3. Mac 128 macrumors 603

    Mac 128

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    #278
    The main problem I have with the inability of the ATV to match native output of the source, is that every TV is different and has different requirements and needs. If Apple made the TV, then they could control the situation however they like. One issue for me are that my Sony 900E will not allow me to adjust the screen dimensions of a native 4K signal, so I cannot use the wide stretch or zoom feature, when in 4K. There are various other settings no longer available to me with a native 4K signal, with which I can otherwise fine tune a 1080p signal. Moreover, you may think the ATV 4K does a decent job at upscaling, but understand I paid a premium for one of the best upscaling TVs around, and therefore am taking a step backward unless I manually adjust it. Until Apple controls the entire experience, as with most of their other products, they need to offer the customer as many options as possible to adapt the technology to their particular TV.
     
  4. andrewstirling, Nov 30, 2017
    Last edited: Nov 30, 2017

    andrewstirling macrumors 6502

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    #279
    Why on earth would anyone want to zoom or stretch the image? This actually upsets me. Haha.

    I have a 65” Oled TV which has an excellent upscaler but I’m pretty happy with the upscaling qualities of the Apple TV. I do think there’s an element of personal preference however. For example, if I have one criticism of the Apple TV upscaling, it’s that it seems to mildly sharpen the image. If I wander over to the Infuse forum however, there’s a thread full of people criticising the Infuse upscaler (it uses its own) as it doesn’t seem as sharp as the native player.

    That being said, there’s no doubt that an option to auto switch resolution would be the best option. I can’t see any reason why they don’t add it to be honest. Maybe if the tech press applied the same amount of pressure as they did over dynamic range and frame rate switching then they’d get it done.
     
  5. WilliamG macrumors G3

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    Seattle
    #280
    I'm not convinced the Apple TV 4K outputs proper 24p, even when set to frame-rate match. I'm getting the occasional frame-skip in playback that's peculiar, and I can't quite put my finger on why. And it's nothing to do with bandwidth or a stream-itself issue. Just feels like the Apple TV is outputting 23.972 or somewhere "around" 23.976fps, but not exactly.

    Anyone else notice such a thing?
     
  6. Scott Davilla macrumors regular

    Scott Davilla

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    #281
    it's pretty exact, I've timed the refresh rate using displaylink.
     
  7. WilliamG macrumors G3

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    #282
    Are you sure, though? Can you explain the frame skips in “Dark?”

    And what is “pretty” exact? What did you time it to be EXACTLY?
     
  8. andrewstirling macrumors 6502

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    #283
    I don’t get any frame skips if that’s any help
     
  9. Scott Davilla macrumors regular

    Scott Davilla

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    #284
    60000/1001 ~= 59.94005994005994

    Debug Print: -[MainController displayLinkTick:]: displayRate = 59.940060

    I'd say that's pretty exact.
     
  10. WilliamG macrumors G3

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    #285
    Sure? But that’s not the frame-rate we’re discussing here.
     
  11. Scott Davilla macrumors regular

    Scott Davilla

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    #286
    my bad :) 24 is the same deal;

    24000/1001 = 23.976023976023976

    Debug Print: -[MainController displayLinkTick:]: displayRate = 23.976024
     
  12. WilliamG macrumors G3

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    #287
    Interesting. Thank you. So I wonder why "Dark" is having issues in Netflix, - though I must be honest I haven't watched anything else. Do you have a way to see what frame-rate that is in?
     
  13. Scott Davilla macrumors regular

    Scott Davilla

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    #288
    Come to think of it, I noticed that last night watching "Dark" too, it did not look like a frame rate issue, more a encoder or decoder glitch. Would freeze for a fraction of a second then jump and continue. Frame rate mismatches don't look like that.

    I can snoop it tonight. The console log shows the requested and obtained display range and rate and other interesting info.
     
  14. WilliamG macrumors G3

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    #289
    Ahhh glad someone else noticed it. I don't seem to be able to recreate it easily, and certainly not at the same time-stamps. Be very interested in what your snooping reveals! Thank you!
     
  15. Scott Davilla macrumors regular

    Scott Davilla

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    #290
    Got nothing for you, head back to camp :)

    One glitch after watching three episodes. But by then I was bored watching log (it gets quite large) and missed it. Near very end of final episode. Also not reproducible.

    But Frame rate switch was correct.
     
  16. WilliamG macrumors G3

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    #291
    Boo. :(

    Thanks for trying, though.
     
  17. 500kilohertz, Dec 12, 2017
    Last edited: Dec 12, 2017

    500kilohertz macrumors newbie

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    Dec 12, 2017
    #292
    I've got the same issues watching Dark on netflix. And I think the Apple TV is not supporting 24hz.

    Don't get this wrong, I'm not talking about 24/1001p or 23.976p. Some German (or European) movies or TV shows are produced with exactly 24 fps! I'm to lazy to calculate this, but you will get a frame skip after about 45 seconds when you play 24fps content with 23.976fps.

    When I activate "match content" I see the following list wiht my 1080p TV:

    1080 - 60hz
    1080 - 50hz
    1080 - 30hz
    1080 - 25hz
    1080 - 24 hz (film)

    So one entry is missing: 23hz or 23.976hz or 24hz. I think the 24hz entry in the list is 23.976hz and the real 24hz is missing. Apple as an US company may have missed something here for the European customers.

    Can someone check this? My Yamaha receiver always shows 24hz, doesn't matter if it is 23.976hz or 24hz.
     
  18. BODYBUILDERPAUL macrumors 65816

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    Feb 9, 2009
    #293
    Guys, this is TOTALLY OVER OBSESSIVE as it's truly out of your control! Crazy. Stop looking for faults and enjoy what you have! :) I'm so glad you didn't live through VHS, grainy analogue satellite and old CRT TV ) :) :) :) :)
     
  19. 500kilohertz macrumors newbie

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    Dec 12, 2017
    #294
    I did live through the analogue TV and VHS times, it was horrible ;)

    I'm an IT guy and I just see these things, can't do anything about it :)
     
  20. WilliamG, Dec 12, 2017
    Last edited: Dec 12, 2017

    WilliamG macrumors G3

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    Seattle
    #295
    This actually makes a lot of sense. The key would be finding out if "Dark" is supposed to be 24fps or 23.976fps. Even so, I'm getting a frame skip far, far less often than every ~41 seconds (it's 41 seconds for the 23.976 vs 24.000 mismatch).

    I know when I use the built-in Netflix app on my LG OLED C7 TV, I get zero frame-skips at all playing "Dark," or any other material. It would make sense that the TV app would play both 24fps and 23.796fps material without trouble.

    *EDIT*

    Confirmed. "Dark" is a 24.000fps - i.e. 24hz exactly TV show. So that appears to me the Apple TV is outputting the wrong refresh rate (in this case - 23.976hz is incorrect), which is causing the frame-skips. So I guess we need to file a bug report with Apple...
    --- Post Merged, Dec 12, 2017 ---
    I filed a bug report and speak to an adviser. Of course this is the first they've heard of this... go figure.
     
  21. Scott Davilla macrumors regular

    Scott Davilla

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    Jan 5, 2016
    #296
    Interesting, tried a 24.000Hz sample. My Samsung UHDTV can do both 24.000Hz and 23.976Hz

    displayRateSwitch request: refreshRate = 24.00, dynamicRange = SDR
    displayModeSwitchInProgress == YES, refreshRate = 24.00, dynamicRange = SDR
    [MainController displayLinkTick:]: displayRate = 23.976025
    displayModeSwitchInProgress == DONE, refreshRate = 23.98, dynamicRange = SDR

    So we asked for 24 but got 23.976025. Opps Apple :)

     
  22. WilliamG macrumors G3

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    Seattle
    #297
    Wait, so you confirmed that the Apple TV is outputting 24.000hz when fed a 23.976hz signal?
     
  23. Scott Davilla macrumors regular

    Scott Davilla

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    Jan 5, 2016
    #298
    The opposite, the app asked for a frame rate of 24.000Hz but got a frame rate of 23.976Hz.

    Apple's frame rate API is a request, you might not get what you asked for. The reason is there is no public API that returns the possible display frame rates. But you can see them in the console log when a hdmi device connects and the EDID is probed.
     
  24. Mac 128 macrumors 603

    Mac 128

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    Apr 16, 2015
    #299
    Anybody check Plex? I'm streaming 24 frame videos via maximum quality, but they're not changing to 24Hz -- the display indicator does not show 24 as it does with other apps. Is it a limitation of the app, or some fault of the transcoding settings?
     
  25. andrewstirling macrumors 6502

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    May 19, 2015
    #300
    It’s the app. It doesn’t use the native video player so needs an update. Both infuse and mrmc have updated their apps so it looks like plex are slow off the mark
     

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