How to get 23,97fps instead of 24?
#1
The question is very simple... how do i have to configure my HTPC to get 23,97fps?

I've try Windows and Linux, Intel and AMD APUs, but I always have 24fps and XBMC has adjust the speed to meet 24fps and avoid judder. Since the TV used does support 23,97fps and graphics cards also does, it must be made via software.

Even if I set 23fps in ATI CCC or Intel software it's really working at 24.

Many thaks in advance
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#2
Anyone can help me?

Regards
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#3
You are most likely confused by what you see on codec screen. fps is a rounded value and will never show 23.97. As long as you don't use passthrough audio it is irrelevant if your systems runs 24 or 23.97. Switch on "sync playback to display" and sync method to resample audio. You will have smooth playback regardless 24, 23.976, or 23.971 (wrong speed o many NVidia systems).
On AMD systems this will result in 23.976 anyway.
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#4
(2014-06-13, 08:39)FernetMenta Wrote: You are most likely confused by what you see on codec screen. fps is a rounded value and will never show 23.97. As long as you don't use passthrough audio it is irrelevant if your systems runs 24 or 23.97. Switch on "sync playback to display" and sync method to resample audio. You will have smooth playback regardless 24, 23.976, or 23.971 (wrong speed o many NVidia systems).
On AMD systems this will result in 23.976 anyway.

Many thanks for your answer, FernetMenta,

The question is I use passthrought, so framerate on 23,976 videos should be this instead of 24 to avoid problems. As far as I'm concerned Haswell are able to do this, and I see "24p" on XBMC when I press "o" key, so it seems to be working at 24, not 23,97

Regards
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#5
(2014-06-13, 08:39)FernetMenta Wrote: You are most likely confused by what you see on codec screen. fps is a rounded value and will never show 23.97. As long as you don't use passthrough audio it is irrelevant if your systems runs 24 or 23.97. Switch on "sync playback to display" and sync method to resample audio. You will have smooth playback regardless 24, 23.976, or 23.971 (wrong speed o many NVidia systems).
On AMD systems this will result in 23.976 anyway.

Wouldn't you want to do the opposite, and sync the display to the playback?
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#6
(2014-06-13, 08:39)FernetMenta Wrote: You are most likely confused by what you see on codec screen. fps is a rounded value and will never show 23.97. As long as you don't use passthrough audio it is irrelevant if your systems runs 24 or 23.97. Switch on "sync playback to display" and sync method to resample audio. You will have smooth playback regardless 24, 23.976, or 23.971 (wrong speed o many NVidia systems).
On AMD systems this will result in 23.976 anyway.
May I ask why do you round the value? It's pretty counterintuitive and for people who elect, for whatever reason and I'm not among them, to use passthrough , it complicates understanding if the selected refresh rate is correct or not.
For troubleshooting and bug reporting please make sure you read this first (usually it's enough to follow instructions in the second post).
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#7
DirectX9 and old xrandr api only returned integer for refresh rate. On Linux this has changed and we get correct floating point values. I have created a pull request which changes the value to float. https://github.com/xbmc/xbmc/pull/4915
Other platforms should follow. Should be simple on OSX and iOS. Windows requires an update to DX10 which is long overdue anyway.

Quote:Wouldn't you want to do the opposite, and sync the display to the playback?

We do. The setting is called "adjust display to match refresh rate". But it may not match 100%.
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#8
(2014-06-16, 17:46)FernetMenta Wrote:
Quote:Wouldn't you want to do the opposite, and sync the display to the playback?

We do. The setting is called "adjust display to match refresh rate". But it may not match 100%.
Most displays today only support a limited amount of fixed refresh rates.

The most commonly supported being 48Hz, 50Hz, 60Hz, 72Hz, 100Hz, 120Hz, 200Hz, 240Hz, so with "adjust display to match refresh rate" XBMC have to match one of those that your display support and is closest to being able to be divided by the frame rate of your video.

Almost no displays today support what is referred to "Variable Refresh Rate", and today only monitors that supports VESA's Adaptive-Sync, AMD's FreeSync, and Nvidia's G-SYNC can achieve a non-fixed refresh rate, which today have almost no monitors on the market yet, and no large screen TVs on the market at all.

http://www.brightsideofnews.com/2014/05/...-standard/

My guess is that probably by the time that HDMI 3.0 is out then that standard will support "Variable Refresh Rate" as an requirement by default.
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#9
Nowadays even the cheapest TVs support the most common refresh rates like 23.796, 24, 29,97, 50, 60, etc. There is only very little demand for VFR.
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#10
First of all, I want to sincerely thank all the answers given in this thread.

My doubt comes from this:

Image

In all the 23,976 videos I play it happends the same, at least apparently the refresh is 24p, and I want it to be 23,976. When I play a native 24p video it appears to be running at actual speed of 24p, having the "speed" at "+0".

I understand that in cases when TV or graphic card doesn't support 23,97p there is no other fix than this (play at 24 and adjust speed to avoid judder), but I've try on TVs that supposedly supports 23,97p (like a Panasonic VT30), and according to this:

http://www.anandtech.com/show/7007/intel...spective/4

Haswell also supports 23,97p.

I made this same question on Intel forums and I were answered that 23,97 is not possible: https://communities.intel.com/thread/52333

Any help?

Many thanks in advance
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#11
again: 24 - 0.1% = 23.976

so where is the problem other than most users can't interpret those numbers?
Note that those numbers do not say anything about actual refresh rate. Assume we are playing some 23.976 video. refresh would say 24, speed +0.1%. If your gfx and display is capable of 23.976, sync will settle down to 0%
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#12
Many thanks for the answer FernetMenta,

I'm not sure if I understand you. You say "If your gfx and display is capable of 23.976, sync will settle down to 0%", so I assume that I'm having an actual refresh of 24p, not 23,976, am i wrong?

My gfx and display are 23,976 capable, so actual refresh should be 23,976. My question is: ¿What is the actual refresh in the image I uploaded?

Many thanks
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#13
The image you uploaded tells us the following:

refresh 24 and speed: 0.1%
this tells us that the initial clock speed is 23.976. this equals fps of the video

error is 6% and average error is at -6%. either you have the video just started and it has not settled or you have a/v sync set to audio (what I don't recommend).

You don't see the actual refresh rate here. DirectX 9 only gets a rounded value from the driver.
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#14
Image

this runs on 23.976.
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How to get 23,97fps instead of 24?0