Best settings for 4K HDR playback?

  • Hi guys, I have 2 Nexbox S905x boxes....1 with latest Kodi 17 Libreelec build on and one on android with the latest SPMC build on and the 4k movies (via Kodi addons) play spot on in the SPMC, but when i try in Libreelec they just freeze after a couple of sessions. Is there possibly something within my Libreelec settings that I could amend for smooth playback? Cheers

  • I started using these ROMs recently. 7 worked fine but 8 was having the exact same buffering problems described here. I knew it wasn't my network or my NAS and even with 100mbs, there should be plenty of bandwidth for movies twice the size as I'm trying. No mater what I tried, none of my Bluray backups would play without skipping/buffering. I wasted a couple of hours messing with settings, with no luck, and I finally got these rips to play 100%. I tried so many things so I can't be certain that this is what finally did it. But what I think it was finally was messing with the advancedsettings.xml file. Setting

    <memorysize>50000000</memorysize>
    <buffermode>1</buffermode>
    <readfactor>6.0</readfactor>

    is what started it working for me. Let me know if this helps your guys' buffering issues. I've only gone through 2 movies but I'm hopeful. I'd rather not run android.


  • I started using these ROMs recently. 7 worked fine but 8 was having the exact same buffering problems described here. I knew it wasn't my network or my NAS and even with 100mbs, there should be plenty of bandwidth for movies twice the size as I'm trying. No mater what I tried, none of my Bluray backups would play without skipping/buffering. I wasted a couple of hours messing with settings, with no luck, and I finally got these rips to play 100%. I tried so many things so I can't be certain that this is what finally did it. But what I think it was finally was messing with the advancedsettings.xml file. Setting

    <memorysize>50000000</memorysize>
    <buffermode>1</buffermode>
    <readfactor>6.0</readfactor>

    is what started it working for me. Let me know if this helps your guys' buffering issues. I've only gone through 2 movies but I'm hopeful. I'd rather not run android.

    I will try this today and report back, thanks


  • I started using these ROMs recently. 7 worked fine but 8 was having the exact same buffering problems described here. I knew it wasn't my network or my NAS and even with 100mbs, there should be plenty of bandwidth for movies twice the size as I'm trying. No mater what I tried, none of my Bluray backups would play without skipping/buffering. I wasted a couple of hours messing with settings, with no luck, and I finally got these rips to play 100%. I tried so many things so I can't be certain that this is what finally did it. But what I think it was finally was messing with the advancedsettings.xml file. Setting

    <memorysize>50000000</memorysize>
    <buffermode>1</buffermode>
    <readfactor>6.0</readfactor>

    is what started it working for me. Let me know if this helps your guys' buffering issues. I've only gone through 2 movies but I'm hopeful. I'd rather not run android.


    <memorysize>50000000</memorysize>

    50000000kb = 48828.125Mb

    I don't think that's right
    How much memory your box have?


  • bytes, yo. no kilo

    I have tried to play with the advanced settings but, at least for me, the issue is the NFS/SMB implementation integrated in Kodi.
    Everything works just fine when my repository is mounted directly via NFS from the underlying OS.

    Edited once, last by r4w (March 7, 2017 at 12:10 PM).

  • I will try your method when I get home. It's still a little temperamental. I always have to pause it a ltitle to buffer before it plays OK. Also, I'm just using ftp, I'll try the other 2 later to. But this seems to have fixed it for me. Still tinkering.

  • I've tried several different USB lan adapters, I still had the exact same buffering problems. But really the network should be able to do many movies like this at once. And my audio would have a loud pop every time it would lag for a second and then catch up. Sometimes popping on and off almost constantly. Not a single Bluray rip would play with out buffering. Sometimes I would get a few minutes but eventually it would start buffering. But now, If I pause for a few seconds in the beginning, It will play through all the way flawlessly.

    I think its the cache settings that finally fixed it for me but I did try two other commands at the same time I can't rule out. I got them from the LE 8 thread. I also gave these 2 commands through ssh. Maybe try them too.

    1.
    echo 5 > /sys/class/mpgpu/cur_freq

    2.
    fw_setenv hdmimode 1080p24hz; fw_setenv outputmode 1080p24hz

    After the second one, I was then able to manually change the refresh rate and resolution in the settings.


  • Not a single Bluray rip would play with out buffering.

    1920x1080 :huh:
    There are many ways ripping standard Bluray

    I'm talking about 4k UHD 10 bit resolution 3840x2160, for me it's not necessary to change buffering settings playing Jellyfish Bitrate Test Files(for example)
    and 4k HDR playback of Sony Camp HDR version(for example).

    In my case I found the bottleneck network and NFS protocol.
    I guess the in Your case there is another reason.

  • I also have 4k stuff that did the same thing. I just noticed that the full BR rips all did it too. That's where I started focusing. 4k also plays for me now. Booth were having the same problem. Looks like I have a new update to try now.

  • Well, as obviously most of us have no problems with freezes during playback, you will need to provide:

    • debug logs. See thread-981.html
    • sample file(s). You can try to cut off a piece from the start of the file and see if it still triggers the bug to make it easier to upload


    I also can recommend to create a fresh install of LE8 on a spare card, double check that you use the right device tree and play the problematic file without installing any addons or changing any settings to rule out a corrupted system or your own setup.


  • Well, as obviously most of us have no problems with freezes during playback, you will need to provide:

    • debug logs. See thread-981.html
    • sample file(s). You can try to cut off a piece from the start of the file and see if it still triggers the bug to make it easier to upload


    I also can recommend to create a fresh install of LE8 on a spare card, double check that you use the right device tree and play the problematic file without installing any addons or changing any settings to rule out a corrupted system or your own setup.

    Thank MMPP, I will look a a debug log. Just as an aside my LE is always on the nand. Do you change any of your settings to play 4k?

    Cheers

  • My only 4k sources are some demo clips, youtube streams and dvb-s2 test broadcasts. I currently use my boxes only with 1080p tv sets, but I do not think the output resolution makes any difference. I tested it once on a 4k hdmi 2.0 set, all was the same.

    Settings-wise I only have added a 3s delay for the frequency adjustment at start/stop, because my tv set takes a little time to digest the change. Almost everything else is stock.