Amazon working on “Cinema Mode” for Fire TV to sync frame rate between video and TV

Deep in the source code of Fire OS 6 on the all-new 3rd generation Amazon Fire TV is an unreleased new setting called “Cinema Mode.” Based on the setting’s description, it appears to enable synchronization between the frame rate of the video being played with the refresh rate of the television. This is a feature that home theater enthusiasts have been wanting for a long time.

All Fire TV and Fire TV Sticks have always displayed their interfaces and content at 60Hz. This means that the image on your TV updates 60 times per second. The more often the image updates, the smoother things like the user interface and games will look. The problem comes when you play a movie or a TV show, which was likely shot at 23.976 frames per second, at that same 60Hz refresh rate. Since the number of video frames available do not match the number of times the TV screen is being changed, you end up with an issue called 3:2 pulldown. Since 23.976 does not divide evenly into 60, the video player must alternate between duplicating 3 frames half the time and duplicating 2 frames the other half of the time. This results in unwanted artifacts appearing on the screen, which are especially noticeable during fast motion scenes.

The solution to the issue is to simply switch the TV to 24Hz when playing video and switch back to 60Hz when displaying other content like the user interface. Fire TV owners used to do this manually by access hidden resolution options, but this often broke or became unavailable with software updates. More recently, media player apps like MrMC, Kodi, and SPMC have been taking advantage of undocumented developer options in Fire OS 5 to switch the Fire TV’s refresh rate automatically when video is played. However, this too has proven unreliable since Fire OS 6 appears to break the functionality.

It seems as if Amazon is listening to enthusiasts who have been asking for official support for refresh rate syncing because Fire OS 6 on the new Fire TV has an unreleased “Cinema Mode” option that appears to officially enable support for switching refresh rates. The setting is described by Amazon in the source code as: “When Cinema Mode is on, supported apps will use native frame rate during video playback. Video Resolution must be set to Auto to enable Cinema Mode.”

For the time being, the Cinema Mode option is not available on any device. Fire OS has a portion of the source code where it specifies which Fire TV and Fire TV Stick models are able to access the various features of the operating system, like UHD resolutions. That code normally returns “true” if certain Fire TV models are used and returns “false” otherwise. The code that relates to Cinema Mode doesn’t currently check for any Fire TV models and simply returns “false” no matter what.

Since this new feature is completely hidden from the user, there is no guarantee that it will ever be released. I have found plenty of hints at new features in the past that we’ve yet to see released, so there’s no telling if a future Fire TV software update will enable Cinema Mode or not. At the very least, it’s great to see that it’s at least being considered and worked on.

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9 comments
  1. S says:

    Is this the FireTV equivalent of what Apple is testing, with frame rate switching on the ATV?

  2. pat russell says:

    do u sel the os fire stick

  3. Wonko says:

    I can’t believe this still isn’t standard practice on all devices. It’s shameful that the picture quality and motion is better through TV apps than Amazon’s own dedicated device. I don’t use my AFTV2 any more because of the jerky mess that is produced over HDMI.

    • Eric says:

      It even got worse.
      For some reason I only started noticing these problems when I switched from my old 720p TV and FTV1 to my new 4K TV and FTV2 about 2 years ago (at least here in germany, I don’t know if there are still differences between international standards as they were back in the CRT age with PAL/SECAM/NTSC).
      Not everything newer has to be better, I learned. This is why I keep my FTV2 for the time being and won’t get the new box. If they even decide to limit this new feature to their newest box, without a good reason (“the older hardware can’t cope with that” or such), I won’t even get another Fire TV, ever. This problem is annoying me for a long time and I don’t just wish, but expect Amazon to come up with a solution. It would be the least they can do. As of now, their product is basically still in its beta phase even 2 years after its release, as long as this isn’t fixed.

  4. Max says:

    Strangely they don’t support the 24/1001 etc. rates, only 24.0 etc. This can be overcome by resampling audio, but why not do it right.

  5. Fred says:

    While they are at it with auto resolution they should auto set the Fire TV resolution to match the currently playing video so as to let the TV do the up-scaling work.

  6. Ben says:

    Even when the source frame rate is 60 Hertz and the TV is set at 60 Hertz, it’s still not very smooth motion. It used to be, but something got broken many updates ago and has never been fixed. This is with Amazon content. Netflix content plays fine. I assume Netflix coded their player better.

    When I tried forcing 24Hz mode on the FTV2 it didn’t noticeably improve motion, but had the side effect of sending the sound completely out of sync. Admittedly this is a while ago.

    • Ermic says:

      They broke some things over time by updating the device. Up to a point it worked fine to wake the FTV2 from stand-by, just push a button on the remote and it will start the TV with it and you see the homescreen after a few moments. Ever since some update about a year ago it doesn’t work like that anymore, not when hooked up to the 4K HDMI Port of my TV (and others I tested it with). The TV will wake up from stand-by, but the screen remains blank/black. Only a restart by holding those two keys on the remote will bring a picture back on the TV. Or just put it in the 1080 Full-HD Port, if you still have a separated one. But something with HDMI-CEC and 4K doesn’t work anymore. I sent my feedback in to Amazon, but this obviously was never fixed.
      To me it seems it all depends on the kind of devices their inhouse testers use (employees who take prototypes home for testing etc.). If their devices, for some reason, don’t have a certain bug – or their testers aren’t bugged by a certain bugged – it is rather unlikely that it will ever get fixed, just by reporting it as a regular, paying customer. At least this is my Impression after years of using Fire TVs (1st and 2nd gen. of box and stick) and following the development of their firmware.

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