No way to set HDMI framerate to 50Hz causes judder

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What steps will reproduce the problem?
1.Playing any 25/50FPS footage which is normal in Europe.
2.
3.

What is the expected output? What do you see instead?
Dropping frames causing video stuttering, audio is OK.

What version of the product are you using? On what operating system?
Latest Chromecast image.

Please provide any additional information below.
The same stuttering can be observed when the HDMI input MythTV is connected to 
is set to 60Hz. But MythTV is a Linux app and the framerate can be set to 50Hz 
which eliminates the problem. 

Original issue reported on code.google.com by per...@gmail.com on 9 Sep 2014 at 12:35

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We should open an new issue-thread. I don't think, that they read any comments 
on closed threads (arrogantly).

Original comment by andre.he...@gmail.com on 27 Nov 2014 at 9:57

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I develop video software for a living and have done so for the last 15 years. I 
fully understand the difficulties in reliably parsing the frame rate from 
streams where the incoming timestamps dictate the rate of video play and the 
joys of HDMI control.

Europe has a large installed base of TVs made prior to the advent of good video 
post processing. These TVs will not cope with 60Hz streams and pull out the 
originating 24Hz/23.97Hz/25Hz content then motion interpolate it to a higher 
rate as many newer sets do.

It is extremely remiss of you not to provide an option to force the default 
output rate of the device to 50Hz as nearly every other player in this space 
has done (albeit it belatedly in some cases). They should also however be 
providing a force 24Hz option too but many don't giving you an opportunity to 
beat the rest.

Original comment by mtortol...@googlemail.com on 27 Nov 2014 at 9:58

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> Blu-ray players can handle this issue because discs have extra metadata that
> would allow players to output at the most suitable rate. This is very hard to
> pull off with streaming content.

If this is a reference to my comment regarding Samsung Blu-ray players doing 
automatic refresh rate switching, note that I talked about *streaming* content, 
not discs. They can automatically switch to 24p or 50p when needed.

It could well be the streaming application that sets the refresh rate (rather 
than the player probing the video stream), though, but IMHO that would probably 
be "good enough" for Chromecast as well - the ability for the Cast receiver to 
set a preferred refresh rate via the API, similar to Android 
"preferredRefreshRate" attribute added to WindowManager.LayoutParams in Android 
5.0 Lollipop for presumably exactly this purpose ( 
http://developer.android.com/reference/android/view/WindowManager.LayoutParams.h
tml#preferredRefreshRate ).

Original comment by anssi.hannula@gmail.com on 28 Nov 2014 at 12:10

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I would advise everyone who has this issue to return their chromecast. Maybe 
that will make google listen. Pretty pathetic.

Original comment by jcabrad...@gmail.com on 29 Nov 2014 at 2:08

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This is awful, it should be easy to allow the HDMI refresh rate to be changed :S

Original comment by luker...@gmail.com on 30 Nov 2014 at 1:03

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"We appreciate everybody's input on this issue. Our engineers have spent some 
time investigating the issue and have worked with our hardware partners to 
consider various solutions. Our conclusion is that the TV is in the best 
position to handle HDMI refresh rates. Chromecast cannot attempt to handle 
changes in HDMI refresh rates since it is very hard to accurately identify the 
incoming frame rate. Also, every time there is a HDMI mode change, it usually 
leads to flashing or loss of picture for a few seconds. Blu-ray players can 
handle this issue because discs have extra metadata that would allow players to 
output at the most suitable rate. This is very hard to pull off with streaming 
content."

Huh?
If the metadata is missing, let the user manually override. (With both a system 
default, and a per-session setting)
If the metadata is there, use it.

Also: Use your Google clout to make sure streams DO CONTAIN this metadata.

Flicker from the TV? Who cares? Switching channels also gives "flicker". I 
don't care if the image is lost for a few seconds just when the casting starts. 
It's at least 5000 seconds of shitty vs. nice motion coming up, so I can 
sacrifice two seconds to get the good version. Makes sense, no?

If you don't take video seriously, what's the point of using your video 
products?

Original comment by patrikfl...@gmail.com on 1 Dec 2014 at 10:27

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... and do you really expect anyone in Europe to buy into Android TV?  More 
beta hardware to go with your beta software... :/

Original comment by Fuzzy...@gmail.com on 4 Dec 2014 at 9:04

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Plees fix

Original comment by magned...@gmail.com on 7 Dec 2014 at 1:12

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The WONTFIX reply of the Google support is unbelievably ignorant. The majority 
of flat screen TV sets even can't reverse the 3: 2 pulldown for 24 Hz source 
material ("inverse telecine"), but doing this correctly for 50 Hz material on 
60 Hz I haven't seen yet.

So for 50 Hz source material the Chromecast is absolutely unusable. For 24 Hz 
source material it is also not acceptable for me. You Americans are used to the 
3:2 pulldown for decades on local TV broadcasts, but we in Europe not. It is 
really an issue, believe me. I will never spend money on VOD content with 3:2 
pulldown. 

The Amazon Fire TV can at least be switched to 50 Hz manually, but also has no 
24 Hz support.

Original comment by jwinckel...@gmail.com on 11 Dec 2014 at 12:04

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I'm surprised that no-one's yet mentioned the fact that running a TV at 60Hz on 
a 50Hz power grid results in a much, much brighter backlight. For ages I 
thought that the LG HDTV I use as a monitor on my PC was just dying, however 
when I switched the PC's display settings from the default 60Hz to 50Hz the 
backlight suddenly started behaving properly, and a blank screen no longer 
looked slate grey instead of black. This also seems true of my other Philips 
HDTV, which has the Chromecast plugged into it. All other HDMI inputs display 
black screens as black screens when the content is set to run at 50Hz, whereas 
the Chromecast output is significantly brighter and more grey. To me, this is 
more annoying than the frame judder as it makes the entire signal look wrong, 
not just the occasional frame.

Original comment by benjamin...@vinari.co.uk on 11 Dec 2014 at 5:22

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Google, please do fix this. All content in europe is in 50Hz so it's 
unwatchable on chromecast. Or allow the choice to manually set the refresh rate 
through the app ... 

Original comment by adresvan...@gmail.com on 16 Dec 2014 at 8:25

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Waoo!!! This can't bee true! Juste tested my new Chromecast, and it is fixed to 
60hz HDMI output?!? All the same problem, as with PS3,PS4 Xbox360, and also now 
Xbox One has big problems in Europe, with 25fps content. Judder on all devices, 
and now also Chromecast. Please learn.. that there is other TV/video systems, 
then USA stuf in ther world. I hope for a fix, before Christmas 2014. Please !!!

Original comment by delin...@gmail.com on 17 Dec 2014 at 4:42

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this makes me think of TiVo which can automatically check what resolution is 
optimal for the television .samma technology should be able to use to check the 
frame rate is optimal for TV

Original comment by anders.l...@gmail.com on 19 Dec 2014 at 6:15

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This is pure laziness mixed with arrogance.

If Google chooses to sell hardware in Europe and only one framerate is 
hardcoded, this would have to be 50fps. Not 60fps. You could even automatically 
select framerate based on location, easy peasy.

Every television can play 24, 25/50, 30/60 fps perfectly, but you only let 
chromecast throw 60fps at it. So chromecast converts every thing (24/25/50) to 
a 60fps stream, because you find it hard work to get the flash out of it during 
a refresh-rate change. This conversion just kills a smooth framerate and a 
enjoyable viewing experience. 

You are going the easy route and it results in a mediocre experience.

Original comment by herbertj...@gmail.com on 19 Dec 2014 at 7:59

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Maybe a stupid question but :

Why not just check the open-source code of xbmx / kodi. They have been able to 
change the output framerate based on the media's framerate for years now. So 
why can't Google just use their code to detect the source framerate?

Original comment by adresvan...@gmail.com on 19 Dec 2014 at 9:27

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Do anyone know, if there is a website, where they are getting started to sue 
Google, for selling products in countries, where there can't be used ?

Original comment by delin...@gmail.com on 21 Dec 2014 at 2:37

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if google are unlikely to offer 50hz as a manual option could someone not bring 
out 'hacked' firmware which will have the 50hz option in it? - also on another 
point on my samsung TV it forces 1920x1080p even if i set the chromecast app to 
720 again there should be a working manual setting for that too that sets the 
tv to 720p but that dont seem to work on my TV

Original comment by andy.ro...@gmail.com on 27 Dec 2014 at 1:52

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"We appreciate everybody's input on this issue. Our engineers have spent some 
time investigating the issue and have worked with our hardware partners to 
consider various solutions. Our conclusion is that the TV is in the best 
position to handle HDMI refresh rates. Chromecast cannot attempt to handle 
changes in HDMI refresh rates since it is very hard to accurately identify the 
incoming frame rate. Also, every time there is a HDMI mode change, it usually 
leads to flashing or loss of picture for a few seconds. Blu-ray players can 
handle this issue because discs have extra metadata that would allow players to 
output at the most suitable rate. This is very hard to pull off with streaming 
content."

This answer is unacceptable.

Whether the tv is in a better position to handle incoming signals is completely 
irrelevant.

How can you sell a product on the European market which is incompatible with 
the region's tv standard? Do you really think a car manufacturer could get away 
with selling cars on the UK market if they insisted on placing the driver's 
seat to the left? Essentially that's what you are doing here.

You have 3 following options:

1. Update firmware to allow for manual refresh rate override. This is already 
standard on other Android based devices and Apple TV.
2. Work with streaming service providers to set 24, 50 and 60 Hz automatically, 
i.e. through flags encoded in the data stream. All newer Samsung devices offer 
this.
3. If non of the above is possible due to hardware limitations, explicit 
disclaimers must be included on product packaging and all other forms of 
product information so consumers are fully aware that your product only 
supports 60 Hz refresh rate.

Original comment by aalb1...@gmail.com on 28 Dec 2014 at 3:31

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 Why the F**k won't you (Google) fix a clear problem? 
24hz is a problem for all !
50hz is a problem for EU an other places

Original comment by tork...@gmail.com on 30 Dec 2014 at 3:56

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Issue 469 has been merged into this issue.

Original comment by anad...@google.com on 31 Dec 2014 at 12:59

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Issue 455 has been merged into this issue.

Original comment by jonathan...@google.com on 31 Dec 2014 at 1:12

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Useless. I thought Google to be a inventive company. There is always a way.

You should stop selling this Chromecast not able to stream content properly, 
and offer a refund for anybody not satisfied. There should be a disclaimer that 
European content in 25Hz is not supported.

Why is Google not listening to its customers?

The only reason I personally have not tried to return my Chromecast is that I 
use it to watch movies on Play Store. But it pisses me off every time I try to 
watch local Norwegian content!

Original comment by stian.i....@gmail.com on 12 Jan 2015 at 5:43

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try changing refresh rate to 59hz, its actually 59.93 or something but it 
depicts the difference in hardware and understanding between PAL and NTSC

Original comment by ian.royc...@emtech-pc.co.uk on 14 Jan 2015 at 12:11

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#74:
What do you mean?

Chromecast locks the refresh rates at 60 Hz and there's nothing the user can do 
to change it.

Original comment by aalb1...@gmail.com on 14 Jan 2015 at 7:58

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This is indeed a bit disappointing since it can't be that difficult to get a 
manual option into this tiny little stick, can it?

Original comment by steffen....@gmail.com on 15 Jan 2015 at 2:15

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This is clearly a bug, as this issue is fixable by Play/Pausing the video 2-3 
times (you don't have to wait, just play/pause repeatedly). Tested myself and 
it instantly fixes the problem in Netflix and Hulu.

Found this solution here:
https://forums.plex.tv/index.php/topic/109586-jerky-video-not-buffering-related/

Without the Play/Pause trick it appears as if Chromecast is dropping frames 
while buffering in the background for the higher quality streams. Usually after 
3-5 minutes, this effect disappears. While this is OK for Netflix, in Hulu you 
get commercials that interrupt the streaming so this happens again and again.

I don't experience this problem in YouTube.

In conclusion I think something could be done about without implementing 50Hz 
support.

Original comment by gugio...@gmail.com on 22 Jan 2015 at 7:38

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This is another matter. Locking to 60Hz will give crappy movements when you 
play 25Hz material. There is no way around that. Other than setting the refresh 
rate to something that can be divided by 25.

Original comment by stian.i....@gmail.com on 22 Jan 2015 at 7:43

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That's true, but this trick combined with my LG TV image smooth function 
completely fixes the problem.

PS4 also outputs at 60Hz, but playback is smooth to the eye from the start.

Original comment by gugio...@gmail.com on 22 Jan 2015 at 7:58

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Or should I say, completely "hides" the problem.

Original comment by gugio...@gmail.com on 22 Jan 2015 at 7:59

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Using frame rate interpolation or similar systems is a work-around not a fix. 
Frame rate interpolation also introduces other problems such as "soap opera" 
effect when playing 25 fps film content.

Original comment by aalb1...@gmail.com on 22 Jan 2015 at 11:31

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I had same on my sony KDL-32D3000, and fixed that by changing the Film mode 
setting to "auto 2". This tells the TV to "provide the original film-based 
content as is. And voila, stutter gone!

Original comment by RemesPat...@hotmail.com on 27 Jan 2015 at 5:29

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BS! If source is 25Hz and Chromecast is locked to 60Hz any magic to fix this 
degrades the image and flow. It's just like putting on blurry glasses when you 
have low resolution and imagining yourself it's hi-res. 

Original comment by stian.i....@gmail.com on 27 Jan 2015 at 5:34

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"I had same on my sony KDL-32D3000, and fixed that by changing the Film mode 
setting to "auto 2". This tells the TV to "provide the original film-based 
content as is. And voila, stutter gone!"

This is 60 Hz -> 24 Hz conversion and has nothing to do with CC's 
incompatibility with 50 Hz sources. No tv can reconstruct the original 25/50 Hz 
content from a 60 Hz HDMI signal.

Original comment by aalb1...@gmail.com on 28 Jan 2015 at 11:01

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No that's true. Even if it looks ok, it isn't because of the internal 
conversion to 60hz inside CC. Hopefully we get an firmware update on that. 

Original comment by RemesPat...@hotmail.com on 29 Jan 2015 at 4:45

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Sad that Google doesn't care about European customers. :( It looks like shit on 
my tv.

Original comment by moraj...@gmail.com on 22 Feb 2015 at 5:25

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I also find this unbelievable.
Claiming that the TV is responsible for handling the HDMI refresh rate is just 
nonsense: If the video source does not send the frames at the correct rate, the 
TV needs to perform magic (i.e. advanced algorithms) to realize this and try to 
correct for it. How can you consider this to be the "best position"?
The fact that some TV:s succeed in certain cases does not justify letting it be.

At the very least, let us control the frame rate manually. 
60, 50 or 23.976 Hz.
Please.

Original comment by hakan.la...@gmail.com on 7 Mar 2015 at 9:46

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Issue 522 has been merged into this issue.

Original comment by jonathan...@google.com on 9 Mar 2015 at 7:52

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Hi,

I am living in France; I just bought a chromecast, but I will return it very 
soon;

It is a pitty that I am not be able to change the framerate;

Of course slow pan and some action films are prohibited and very distracting;

Others films are unwatchable.

Please, just let us change change framerate, a least for 50hz (European, 
Australian...) 

Original comment by fjhdav...@gmail.com on 18 Mar 2015 at 6:05

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Just fix it!
Gunnar SWeden

Original comment by gunnar....@gmail.com on 26 Mar 2015 at 9:54

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Unbelievable ignorance and/or technical incompetence. Will never buy this 
broken crap and tell anyone elso to not buy this either. Will buy an Amazon 
Fire instead.

Original comment by jung.rup...@gmail.com on 29 Mar 2015 at 3:32

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Can't believe Google response. As others said, it denotes ignorance about the 
issue and arrogance. Chinese Android TV boxes do fix this, yet Google says it's 
not an issue. I'm a video engineer and I am simply astonished. I really hope 
Android TV in the future doesn't go this route as it currently does, too.

Original comment by kike...@gmail.com on 30 Mar 2015 at 11:27

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Was going to recommend one to my Brother but now will suggest he goes for a Roku

Original comment by MIGLET...@googlemail.com on 30 Mar 2015 at 7:10

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Very ignorant, Google.  Add the 10 lines of code so we can choose manually the 
refresh rate please.

Original comment by Tonio.Ro...@gmail.com on 2 Apr 2015 at 6:49

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The correct fix would be to default the Chromecast to 50Hz in Europe. Given 
Chromexasts are already built to specific country builds, that shouldn't be too 
difficult to achieve.

Picture quality for BBC iPlayer and other major content partners in the UK is 
poor, since they all produce 50Hz-compatible content.

Original comment by ja...@cridland.net on 10 Apr 2015 at 11:22

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Forcing 50Hz is good for 50Hz content, but makes it worse for 24Hz content! So 
not a good solution for everyone.

Original comment by hakan.la...@gmail.com on 10 Apr 2015 at 11:24

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@ #95:

Nope, the correct fix is to read the framerate from the video's metadata and 
then switch to a suitable 24Hz/50Hz/60Hz video mode based on that.

Like, say, every other video player out there, e.g. Kodi/XBMC.

Original comment by zulla.ha...@gmail.com on 10 Apr 2015 at 11:30

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Then I can see why Google have marked it as a wontfix, since they don't want 
flickering screens. This isn't what Amazon's Fire TV nor Apple TV does.

Original comment by ja...@cridland.net on 10 Apr 2015 at 11:33

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That is unfortunate, but understandable. What is not understandable, though, is 
not having the ability override this and set it manually, either in app or in 
devel chrome extension. This option might not be used by masses (who prefer 
flicker free 60Hz with some kind of motion interpolation), but is crucial for 
the few of us who appreciate true 24p cadence of movies. Or for anyone who is 
used to watch PAL region content in its natural framerate.

Original comment by ondrejpe...@gmail.com on 10 Apr 2015 at 11:49

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It turns out that Apple TV *does* switch between 60Hz and 50Hz depending on the 
video type. (This is a controllable setting, as I understand it).

My suggestion would be, then: default at the correct frequency (60Hz for the 
US, 50Hz for Europe), but add a setting to switch to the native resolution if 
desired. I don't know enough about HDMI to know whether the TV advertises what 
is supported: I can understand that 50Hz might not be supported on a US 
television, for example.

Original comment by ja...@cridland.net on 10 Apr 2015 at 4:18