24hz with Netflix films via fire TV stick 4K ?

panman40

Distinguished Member
Joined
Oct 19, 2008
Messages
20,949
Reaction score
8,549
Points
4,026
Can someone please confirm they are able to get films from Netflix on the Amazon fire TV stick 4k to play at 24hz ?.
Despite "match frame rate" switched ON they playback at 60hz ?.

Yet with prime films I get the message it's changed frame rates but then suffer lip sync issues..

I'm checking the frame rates by opening the marantz receiver app on my ipad.

Any help much appreciated!.
 
No it doesn't work, probably in some half baked scheme to stymie the competition. Quite honestly the handling of 24hz on streaming boxes is a tangled mess of rubbish. From what I can gather the only external device that does 24hz correctly on Netflix(ie actually at 23.976, for example the Shield is fixed at exactly 24) is the Apple TV but then that doesn't frame match Amazon which in fairness seems like its really doing 23.976 into 24 on the fire stick which then leads to lip sync issues and dropped frames every few seconds.
 
No it doesn't work, probably in some half baked scheme to stymie the competition. Quite honestly the handling of 24hz on streaming boxes is a tangled mess of rubbish. From what I can gather the only external device that does 24hz correctly on Netflix(ie actually at 23.976, for example the Shield is fixed at exactly 24) is the Apple TV but then that doesn't frame match Amazon which in fairness seems like its really doing 23.976 into 24 on the fire stick which then leads to lip sync issues and dropped frames every few seconds.

Thanks,
What a mess, your last comment about 23.967 being 24 on prime is exactly one issue I have, lip sync and a skip in motion every few seconds, how come so many others are happy with this or don't even have the issue I wonder...
 
This is a complex subject... and it's been covered in other threads, but here's some background:

There are multiple issues which are all getting conflated into one...

Firstly, Newer Amazon Fire TV devices *fully* support native frame rate switching - but the NetFlix App on Fire TV does not. NetFlix need to add support to their App, and so far they have not done this on the Amazon platform.


There's some confusion here about 24 frames or 23.967 Hz refresh. Fractional frame rates are a consequence of some fudging that had to be done because the American NTSC broadcast (analogue) TV system was refreshed at 59.97 Hz and not exactly 60 Hz. The change to 59.97 Hz was made to facility colour broadcasts in the 1950s. For legacy and compatibility reasons 59.97 Hz is still used today on digital platforms.

The vast majority of movies are encoded at 23.967 for home distribution as this matches the 59.97 Hz rate. However, some movies are encoded at exactly 24 frames per second and blu-ray and other systems accommodate both.

Some older Onkyo AVRs (such as the TX-NR808) used to have a Faroudja DCDi processor which couldn't deal with 23.967 Hz properly - this caused a very noticeable video stutter every 41 seconds (audio wasn't affected).

Lip-sync issues occur because the video and audio streams are split, decompressed and processed separately, and then re-combined for output - but there's no mechanism to ensure the video and audio always remain exactly in sync during output. Sometimes fast forwarding or reversing will cause the problem. This issue still occurs, but 23.967 vs 24 isn't the reason for it.

If you're seeing video stutter which repeats in a completely predictable way for the duration of the movie, then this *may* be a 23.967 vs 24 Hz problem. If you 'lock' or force a device to output at exactly 24 Hz and the video is encoded at 23.967, then this will be the effect you're seeing. Most of the time it's actually very difficult to truly differentiate between the two as 24 Hz is often used generically to include both 24 Hz and 23.967. They are only 0.1 of a second different.

Another source of frustration is 50 Hz UK/European content that gets converted to 59.97/60 Hz for output via various streaming devices and apps. It looks horrible.

BBC iPlayer on Amazon Fire TV outputs correctly and uses the native rate of 25 frames per second (50 Hz) but a BBC programme (for example) streamed via NetFlix on the Fire TV converts it to 60 Hz with all the finesse of a bull in a china shop.

Regards,
James.
 
Last edited:
My fire stick 4K judders when watching iplayer and Netflix on my Sony 9005f. I have had to revert to using the TVs inbuilt versions.
 
There's some confusion here about 24 frames or 23.967 Hz refresh

Probably typos...

It should be 23.976fps (not 23.967), which gets abbreviated to 23.98fps but is handled as 23.976fps (VFX software can use 23.976fps explicitly as it will also support true 23.98fps).

Consumer 24fps is 23.976, whereas cinema 24fps is true 24fps but cinemas also support 23.98fps for digital.

The other main frame rate is 59.94fps (not 59.97fps) but professional equipment will also have true 60fps options.

Most feature films are shot at either 24 or more commonly 23.98fps, there are some productions/TV that shoot at 25, 29.97, 48, 59.94, 60 and 120fps plus we can shoot at much higher frame rates for slow motion.

If shooting at 24fps audio is recorded on set at 48.048 kHz, which when the audio and 24fps video is slowed down to 23.98fps makes the audio sample rate 48Khz.

Part of every feature film setup is defining what frame rate and audio sample rate is being used and doing a long duration (full camera mag) audio/video sync test involving camera, dailies and editorial departments to confirm everything is correct.

J
 
This is a complex subject... and it's been covered in other threads, but here's some background:

There are multiple issues which are all getting conflated into one...

Firstly, Newer Amazon Fire TV devices *fully* support native frame rate switching - but the NetFlix App on Fire TV does not. NetFlix need to add support to their App, and so far they have not done this on the Amazon platform.


There's some confusion here about 24 frames or 23.967 Hz refresh. Fractional frame rates are a consequence of some fudging that had to be done because the American NTSC broadcast (analogue) TV system was refreshed at 59.97 Hz and not exactly 60 Hz. The change to 59.97 Hz was made to facility colour broadcasts in the 1950s. For legacy and compatibility reasons 59.97 Hz is still used today on digital platforms.

The vast majority of movies are encoded at 23.967 for home distribution as this matches the 59.97 Hz rate. However, some movies are encoded at exactly 24 frames per second and blu-ray and other systems accommodate both.

Some older Onkyo AVRs (such as the TX-NR808) used to have a Faroudja DCDi processor which couldn't deal with 23.967 Hz properly - this caused a very noticeable video stutter every 41 seconds (audio wasn't affected).

Lip-sync issues occur because the video and audio streams are split, decompressed and processed separately, and then re-combined for output - but there's no mechanism to ensure the video and audio always remain exactly in sync during output. Sometimes fast forwarding or reversing will cause the problem. This issue still occurs, but 23.967 vs 24 isn't the reason for it.

If you're seeing video stutter which repeats in a completely predictable way for the duration of the movie, then this *may* be a 23.967 vs 24 Hz problem. If you 'lock' or force a device to output at exactly 24 Hz and the video is encoded at 23.967, then this will be the effect you're seeing. Most of the time it's actually very difficult to truly differentiate between the two as 24 Hz is often used generically to include both 24 Hz and 23.967. They are only 0.1 of a second different.

Another source of frustration is 50 Hz UK/European content that gets converted to 59.97/60 Hz for output via various streaming devices and apps. It looks horrible.

BBC iPlayer on Amazon Fire TV outputs correctly and uses the native rate of 25 frames per second (50 Hz) but a BBC programme (for example) streamed via NetFlix on the Fire TV converts it to 60 Hz with all the finesse of a bull in a china shop.

Regards,
James.
Any news of this has been fixed yet? Having this work would negate the need for a 120HZ panel which would help me a lot!
 
If you need frame rate matching then ATV is the best. It's not perfect but it's better than the rest AFAIK.

FireTV stick was quite painful with non-prime apps as it was outputting at 60Hz causing micro stutters and some ugly movement around actor's heads and juddering slow panning shots.
 
If you need frame rate matching then ATV is the best. It's not perfect but it's better than the rest AFAIK.

FireTV stick was quite painful with non-prime apps as it was outputting at 60Hz causing micro stutters and some ugly movement around actor's heads and juddering slow panning shots.
If you sideload kodi and run the Netflix and Disney plus add ins, you get perfect frame rate matching. Only thing you can’t do is Apple TV content in kodi. But then the Apple TV 4K box doesn’t do 24 frame properly so any content mastered that way has stutters. 23.976 is ok but not 24 frame. Lots of posts about this in the Apple TV forum Here
 
If you sideload kodi and run the Netflix and Disney plus add ins, you get perfect frame rate matching. Only thing you can’t do is Apple TV content in kodi. But then the Apple TV 4K box doesn’t do 24 frame properly so any content mastered that way has stutters. 23.976 is ok but not 24 frame. Lots of posts about this in the Apple TV forum Here

I am aware of that but I would.take that over 60Hz forced output which was causing above-said issues. Star Wars was a pain to watch

Also heard that Apple TV app on non-ATV platforms have peak bit rate capped at 15 Mpbs as opposed to ATV bit rates 25-31 Mpbs.
 
Hi Guys,
Sorry to drag up an old thread, I'm talking to Amazon support at the moment about the Fire Cube (and I believe Fire Stick 4K Max) devices that currently do not support 24.00hz in their native format with the current Fire OS on them and they force everything to 23.976hz causing a horrible stutter).

My old original Fire Stick 4K (non-Max) DOES support 24.00Hz

Does anyone have any Prime Video examples shot in 24.00fps I can use with them as I'm only coming up with Netflix and Disney+ (or Plex) off of the top of my head right now.
 
Hi Guys,
Sorry to drag up an old thread, I'm talking to Amazon support at the moment about the Fire Cube (and I believe Fire Stick 4K Max) devices that currently do not support 24.00hz in their native format with the current Fire OS on them and they force everything to 23.976hz causing a horrible stutter).

My old original Fire Stick 4K (non-Max) DOES support 24.00Hz

Does anyone have any Prime Video examples shot in 24.00fps I can use with them as I'm only coming up with Netflix and Disney+ (or Plex) off of the top of my head right now.

24 or 23.976?
 
@lgans316 24.00fps / 24Hz native format movies/shows.

As when played at the locked 23.976 the Fire Cube forces you have a horrible judder/ You can let it run at 60Hz and make the best of things but you can see it's not native frame-rate to refresh matching.

The content is as smooth as butter on the original 2018 Firestick 4K output to the same TV/Projector so it's definitely a FireOS implementation limitation on the newer devices.
 
Hi Guys,
Sorry to drag up an old thread, I'm talking to Amazon support at the moment about the Fire Cube (and I believe Fire Stick 4K Max) devices that currently do not support 24.00hz in their native format with the current Fire OS on them and they force everything to 23.976hz causing a horrible stutter).

My old original Fire Stick 4K (non-Max) DOES support 24.00Hz

Does anyone have any Prime Video examples shot in 24.00fps I can use with them as I'm only coming up with Netflix and Disney+ (or Plex) off of the top of my head right now.

I have seen issues in the past with a Faroudja DCDi upscaler and deinterlacer (present in a Onkyo TX-NR808 AVR) which expected exactly 24 Hz, and it caused a frame stutter ever 48 seconds when 23.976 was received. But this was 12 years ago. It was possible to fix the issue by disabling the Faroudja processor altogether.

Usually, the difference doesn’t matter. Blu-Ray supports both exactly 24 Hz and 23.976 Hz. As it does exactly 60 Hz and 59.94 Hz.

I would have thought the video streaming services would be almost universally 23.976 Hz?

I’m afraid this is an issued caused by the introduction of Color to the American NTSC TV standard in the 1950s. 60 Hz became 59.94 Hz and we’re still seeing the knock on affects today - even though NTSC is long since dead, the USA still uses 59.94 Hz for video signalling.

Most display devices / can’t deferentiate between the two frequencies as they are so close, and usually just say 24 Hz for both.

I’m afraid I don’t have a solution, just a question: do you want to force a specific output frequency regardless of how the content has been encoded, or do you want the Fire TV output to exactly match the encoded frequency in the stream?

Regards,
James.
 
I have seen issues in the past with a Faroudja DCDi upscaler and deinterlacer (present in a Onkyo TX-NR808 AVR) which expected exactly 24 Hz, and it caused a frame stutter ever 48 seconds when 23.976 was received. But this was 12 years ago. It was possible to fix the issue by disabling the Faroudja processor altogether.

Usually, the difference doesn’t matter. Blu-Ray supports both exactly 24 Hz and 23.976 Hz. As it does exactly 60 Hz and 59.94 Hz.

I would have thought the video streaming services would be almost universally 23.976 Hz?

I’m afraid this is an issued caused by the introduction of Color to the American NTSC TV standard in the 1950s. 60 Hz became 59.94 Hz and we’re still seeing the knock on affects today - even though NTSC is long since dead, the USA still uses 59.94 Hz for video signalling.

Most display devices / can’t deferentiate between the two frequencies as they are so close, and usually just say 24 Hz for both.

I’m afraid I don’t have a solution, just a question: do you want to force a specific output frequency regardless of how the content has been encoded, or do you want the Fire TV output to exactly match the encoded frequency in the stream?

Regards,
James.

Weirdly that's the amplifier I had before my current one :)

Exactly what you're saying. The Firestick 4K 2018 CAN exactly match the content's original encoding ('Night Clerk on Netflix is an example filed at 24.00Hz).

The Fire Cube 2nd Generation has a weird bug where when it sees a 24Hz (24.00fps) video it switches to 23.976Hz as it thinks it's close enough then you get a lovely judder-judder-judder-judder on output.

I'm looking for more examples that don't come from Disney+ or Netflix (or Plex/Kodi) at the moment. The Amazon Devs aren't interested if it isn't Amazon/Prime Video content unfortunately. I did see something but I can't remember what it was now in all my testing.

I thought it was 'Wheel of Time' but that doesn't seem to display the judder for me so that must be a native framerate for the device.
 
24 or 23.976?

The US use fractional frame rates due to the decision to change their TV system from exactly 60 Hz (2 x 30 interlaced fields per second) to 59.94 Hz in the 1950s. This was done to accommodate Color in NTSC and to prevent interference on existing black & white sets.

This also impacts 24 frames per second content which becomes 23.976 Hz.

23.976 Hz maintains parity with 59.94 Hz.
3:2 pull down is a technique used to ‘fit’ 24 progressive frames into 59.94 interlaced fields. Speed parity is important so the audio remains in-sync with the video.

It’s a shame this is still a thing, and still causes problems in 2022. 😕.

Regards,
James.
 
Definitely still a thing :)

Amazon hardware/FireOS devs can definitely fix it and allow their devices to support all of these standards on framerate matching, they just forgot/didn't bother on the newer devices.
 
@lgans316 24.00fps / 24Hz native format movies/shows.

As when played at the locked 23.976 the Fire Cube forces you have a horrible judder/ You can let it run at 60Hz and make the best of things but you can see it's not native frame-rate to refresh matching.

The content is as smooth as butter on the original 2018 Firestick 4K output to the same TV/Projector so it's definitely a FireOS implementation limitation on the newer devices.

Looks like FireTV doesn't frame rate matching properly.

ATV had similar problem but they fixed this last year. It supports frame rate matching on all apps (at least the ones I use).

 
I saw AFTV spoke about it a while ago and mentioned it was coming to FireOS... there's a sub-note in there that says it was coming to the Fire Cube later (and I guess the Firestick 4K Max).

Looks like they added 23.976 but forgot 24 :rolleyes:


The top of this thread confirms the Kodi guys have seen the same issue as well:

 
It's a shame that we can't all just enjoy 120 FPS.
:laugh: I guess it's what it's divisible by to not drop any frames. I think on my current HDMI run I can only pass 4K HDR at 60Hz to the projector.
 
Peter Jackson filmed at 48 FPS & it looks fantastic.

I don’t agree that high frame rate looks fantastic. Not for movies at least. This is probably because we are so used to seeing films with a slow frame rate - it’s part of what makes them filmic.

High frame rate can look good for Documentaries and Sports.

I saw the last Hobbit movie at the cinema projected at 48 FPS, and didn’t like the experience at all.

I have ‘Billy Lynn’s Long Halftime Walk’ and ‘Gemini Man’ on 60 FPS UHD Blu-ray and these both feel super-real and ‘other worldly’ in a very odd way.

They look amazing with perfect picture clarity and the motion is super smooth, but at the same time it feels wrong. We are used to motion blur in movies.

I can only stand watching High Frame content for about 20 mins at at time. I’ve never got through either movie.

Purely subjective of course.

But I don’t think the majority of movies are going to move away from 24 FPS anytime soon.

Regards,
James.
 
I don’t think the majority of movies are going to move away from 24 FPS anytime soon.
That is a crying shame, I watch 60 FPS all day every day & would bump it up to 120 FPS if it were easier.
 

The latest video from AVForums

Is Home Theater DEAD in 2024?
Subscribe to our YouTube channel
Back
Top Bottom