Dumb mistake? Pi 3, to Pi 4, Kodi UI is only slightly faster, even at only 1080p?

  • I updated a Raspberry Pi 3B to a 4B.

    Considering the 4B is rated as a 4k device and I have a 1080p TV, I was convinced, the UI of Kodi / LibreElec would be wonderful. Dead smooth 60fps.

    As it stands, it looks about 15 to 30% better than my Pi3B :(


    It's most noticable scrolling a list of thumbnails up and down, it's juddery, looks like 20fps maybe?

    I know it's not a software / driver bug, kinda - because if I drop to 720p it's very smooth, so it's probab not a setting?

    This is both 50 and 60hz modes.



    Am I doing something wrong? I updated my Kodi machine specifically in the hope of making my wife find the Kodi experience more pleasant, I have a hard time getting her to use it.

    Pi 4B, 4GB


    Anyone seen this? Any comments? Is the UI being improved for frame rate?

  • RPi3 is using video driver code honed over seven years and millions of installs. RPi4 is using different video drivers that have been around for about nine months (if you include the alpha period) and things are still being fettled into good shape.Things continue to improve over time and with each bump in firmware and drivers.

  • Ok sorry to complain.


    I kinda assumed the GPU in the pi 4, may be backwards compatible and have a honed driver.


    fingers crossed this evolves in time, because if it’s this slow in 1080p, I feel sorry for 4K users

  • From my experience with Pi3 the GPU overclocking helps a lot with GUI smoothness. "force_turbo=1" is required as well.

  • I have the latest firmware on the device, I think, which should reduce the likelyhood of cooking the device, right?

    I'm about to get a Flirc case, which should (somewhat) alleviate issues, so I guess I'll consider overclocking.


    I hope Chewitt is correct and this is something which will improve in time (??) because I'm kinda shocked a 4k device at 1080p is like this.

  • While I'm here though, can I ask, do any Pi4 owners here run the unit at 4 k? if so how do you find it performs at that even higher resolution?

  • It runs okay at 4K resolution output with the GUI set at 1080. But there is still tearing on the GUI at this time. The GUI at 4k is pretty slow.


    The big factor for me is that it lacks deinterlace in hardware making SD and HD (1080i) video from broadcast sources unusable. Video stutters and freezes. This is stopping me replacing my pi3 with this.


    Actual 4k h265 seem okay on the few test files I have provided the data rate isn't too high, struggled with 140Mbs file I tried.

  • Software deinterlaced 1080i content is no drama as long as you do not whitelist the 25/29.97/30 Hz refresh rates in video settings which allows Kodi to run at 50/59.94/60 instead.

  • It runs okay at 4K resolution output with the GUI set at 1080. But there is still tearing on the GUI at this time. The GUI at 4k is pretty slow.


    The big factor for me is that it lacks deinterlace in hardware making SD and HD (1080i) video from broadcast sources unusable. Video stutters and freezes. This is stopping me replacing my pi3 with this.


    Actual 4k h265 seem okay on the few test files I have provided the data rate isn't too high, struggled with 140Mbs file I tried.

    Ok but how is the GUI performance, general scrolling TV and movies at 4k UI?

    I truly hope this improves in the coming 3 to 6 months :/


    I've had no issues with playback, yet. No 4k content, no 4k options for me. I just wanted a great 1080p unit.

  • Software deinterlaced 1080i content is no drama as long as you do not whitelist the 25/29.97/30 Hz refresh rates in video settings which allows Kodi to run at 50/59.94/60 instead.

    I have nothing in my whitelist and the "resolution" is 4096x2160p, "refresh rate" 30, "limit gui size 1080p.


    If I whitelist 1920x1080p the TV switches resolution when I watch HD TV and it works, but is obviously slow to switch as it renegotiates.


    But my TV won't take SD content like DVDs so can't pull the whitelist trick. Or any SD TV channels.

  • I have nothing in my whitelist and the "resolution" is 4096x2160p, "refresh rate" 30, "limit gui size 1080p.


    If I whitelist 1920x1080p the TV switches resolution when I watch HD TV and it works, but is obviously slow to switch as it renegotiates.


    But my TV won't take SD content like DVDs so can't pull the whitelist trick. Or any SD TV channels.

    If you want decent deinterlacing of broadcast TV you need to ensure your refresh rate includes 50 and/or 59.94 modes (50 if you are in a 50Hz territory - Europe/Aus/NZ, most - if not all? - of Africa and lots of Asia and bits of South America, 59.94 if you are in a 60Hz territory like North America, Mexico Japan, Korea, Brazil and some other bits of Asia and South America)


    2160p 30Hz modes are going to be very juddery for native interlaced content - which will be running at a higher rate than can be displayed cleanly at 30Hz.

  • Software deinterlaced media will play terribly if forced to 25/29.97/30 modes as Kodi currently renders each half-frame as a whole frame, so you need the "double" refresh rate to get all the frames rendered. If you force 25Hz content to play on a (4k)30Hz mode you're probably missing 50% of the half-frames in the video stream. I have Kodi set to 1080p60 and I whitelisted the 4K resolutions and 1080p 23.976/24/50/59.79/60 modes. The GUI plane is rendered at 1080p by default so you won't see any real-world difference from having the resolution at 4k but the GUI takes less effort to render so navigation is a little snappier and Kodi will still switch to 4k modes if you play 4k media. If you mostly watch deinterlaced 1080p PAL media 1080p50 may be a better default as this avoids the 60>50 mode change.

  • Software deinterlaced media will play terribly if forced to 25/29.97/30 modes as Kodi currently renders each half-frame as a whole frame, so you need the "double" refresh rate to get all the frames rendered. If you force 25Hz content to play on a (4k)30Hz mode you're probably missing 50% of the half-frames in the video stream. I have Kodi set to 1080p60 and I whitelisted the 4K resolutions and 1080p 23.976/24/50/59.79/60 modes. The GUI plane is rendered at 1080p by default so you won't see any real-world difference from having the resolution at 4k but the GUI takes less effort to render so navigation is a little snappier and Kodi will still switch to 4k modes if you play 4k media. If you mostly watch deinterlaced 1080p PAL media 1080p50 may be a better default as this avoids the 60>50 mode change.

    Absolutely spot on - I have pretty much every LibreElec and CoreElec Kodi device I run configured like this, and watch a lot of interlaced content, but also quite a lot of 23.976/24Hz stuff, and some UHD/4K.

  • Thanks for all the info.


    If I switch the display to 1080p50 how well is standard def content handled on the pi4?

  • If you are going to set a single resolution and no whitelist 1080p60 is the best option. If you're going to change the default to 1080p50 as most of your media is PAL (25Hz) then it will eliminate most-switching (as Kodi doubles 25 to 50 automatically so no switch is required) but it would be best to use the whitelist and allow 23.976/24/50/59.94/60 modes. I don't see any issues with SD media. YMMV.

  • Thanks for the info.

    Is it at all practical to run at 4096p50 with GUI at 1080p? To avoid any mode switching at all, other devices seem to be doing this. Or is this not currently practical on a rpi4?


    This would be more useful as now I can only easily see still photos in 1080p.

  • It's possible but you're forcing all SD and 1080p media to be upsampled to 4K which takes some effort and this will refect in power consumption, heat output and overall load on the (better than RPi3 but still low-power) device. You'll see better overall performance running resolution and GUI at 1080p which suits the majority of media while the small subset of 4K media switches. At some point the balance of media being 4K might shift, but that's still some way off in the future and there'll probably be a higher spec RPi4 or even RPi5 by then :)