Windows 10 vs Windows 11 for NextPVR

[mvallevand]

Pretty sure for you 1080i is always half the fps. This is an old article https://www.bbc.co.uk/blogs/researchandd...d-on.shtml but it helps explain some of the issues decoding BBC content. I am not sure what happens on your STB when 1080p is received.

Is your playback issue only on BBC or all channels since it could be something else entirely.

Martin

[three6zerocool]

I believe it happens primarily on certain content, but only from STB.
Mediainfo reports a GOP of 3 for the 1080/25 recordings and h264 profile of 3.1.
Media info reports GOP of 4 and h264 profile of  4.2 for the NZ DVB-T broadcasts.


I like the WWE Wrestling, and I see the micro-stutter regularly when watching that live, or from recordings of that show via STB.
I know WWE broadcast the wrestling in the USA in 720p (HD as they call it)

I also watch Dukes of Hazzard, and see the odd micro-stutter there to, and also when watching Knight Rider.

I should really watch using NextPVR client and see what happens, as I think it could be Kodi causing this.

Does it matter the default Kodi screen refresh rate?
ie. Most broadcast content here in NZ is 50hz,  and on the Fire Cube in the Kodi app, it defaults to 59.94, but have options of 60, 50, etc.

In the PVR section I have the fallback rate set to 50.


I have changed the STB to output 720p currently.

[mvallevand]

I thought you were in the UK sorry. You probably have just 1080i and maybe the stutter is de-interlacing. 720p might help.

If Kodi is switching to 50 you shouldn't have judder, if it doesn't switch forcing it would be better than 59.94.

Stutter is missed or skipped captured frames. Judder is when the FPS rates don't match.

Martin

[three6zerocool]

Update 2:

I think Martin is correct, in that I think the micro-stutter I occasionally see is something to do with deinterlacing.

I disabled Kodi Hardware decoding of MediaCodec Surface on my Fire TV Cube,  and then found the software deinterlacing options become available when playing back the 1080i STB recordings.
Seems to work really good, but of course without hardware decoding active, none of my 4k movie collection can playback properly.

Is there are way to make Kodi not use hardware decoding when playing back a particular file type?
ie. NextPVR recordings ending in .TS  (h264, AVC)

I seem to remember with older versions of Kodi, one could use deinterlacing and bob invert, and that would give good playback of my recordings from USA sources here in New Zealand.

[mvallevand]

I noted lack of de-interlacing might be the cause of stutter, that is client based, so of course Win 10 vs Win 11 would not be an issue. However if h/w deinterlacing is causing an issue that is another factor altogether.

If you have move to 720p 50 that takes deinterlacing out of the equation.

Martin

[three6zerocool]

Yes, I think you are correct.

I will change the output of the STB to 720p for a longer time and see what happens.

For me, is a kind of mental thing, where 1080 sounds higher number than 720.  (tho to be honest I cannot see any real difference in the recorded content I watch)
As you say, the version of Windows OS is not an issue,   and Sub said his development Windows machine is Windows 11, so thats a good enough recommendation for me to use it also.

[three6zerocool]

Update 3:

Made some progress in testing.

After changing my STB's output to 720p, the weird micro-stutter persists, and perhaps is a bit worse.

I now theorize that the issue is with Kodi, but I did find a fix that resolved the micro-stutter, and that was to enable the Kodi playback option 'sync playback to display'
Of course that nukes passthrough audio, which is not a viable permanent option for me.

I also discovered that there is an Audio passthrough problem with Fire TV Cube 3rd gen (which I have) that causes out of sync audio, and is apparently a problem with the firmware on these devices.
Kodi developers have made a fix in Kodi Omega.

I definitely have the above out of sync audio issue when using passthrough audio with Fire TV Cube, and I tried latest Omega Apha and it resolved the audio, but still have the microstutter, just like Nexus.
However while messing around with passthrough audio, I discovered the Kodi setting for raw passthrough audio, and with that enabled instead of the default one of IEC (or similar),  I don't seem to see the microstutter in live TV. (or not so far anyway)

So, my theory is that it is not and interlace or Windows 10v s 11 thing, but could be an issue with Kodi and passthrough audio.

[three6zerocool]

Update 4:

Ok, looks like it is a Kodi play back issue.
I was wrong, and the 'sync playback to display'  option still does not fix the stutter.

I performed some recordings from my STB set to 1080i.
I then watched the recording using Kodi on Fire TV Cube, and happened to see the stutter virtually immediately.

I then exited Kodi, and ran NextPVR UI Client on the same FireTV Cube,  and played back the same recording, and it plays perfect with no micro-stutter at all on the same section of video.
So, guess that eliminates any kind of recording issue with NextPVR, and proves that it is a Kodi issue, and irrelevant to this thread.

Next I am gonna check my NVidia Shield Kodi client, and see what it thinks of that same content.
Just did that check, and the Kodi on the Shield managed to play that recording without Stutteriing.

Interesting.