Megogo MXV 4K (Amlogic s905) 4k video not working

  • I am trying to setup LibreELEC on Megogo MVX 4K (Amlogic S905 1G/8G Gigabit Lan)
    There are 3 issues: Remote, LAN and the bigest problem is that the 4K videos will not play with none of the dtb files.
    I tested all the dtb files and found two of interest:
    - meson-gxbb-kii-pro (This one wil make a perfectly functional remote/power/led but no LAN and no 4K)
    - meson-gxbb-vega-s95 (Remote does not work properly but LAN work. 4K not working)

    Here are some insights:

    STOCK ANDROID 5.1.1 firmware
    Kodi won't change resolution based on video size
    Kodi works only on system set resolution and that can't be changed from within Kodi. 4k video looks good when sys set res is 4k60hz
    No video player adjust display to video
    Most 4k video works in vlc without changing res/refresh rate (maybe it does resampling). The image looks better when device is set to 4k60Hz
    Some 4k sources are pixelated
    Hardware acceleration: MediaCodec

    LIBREELEC firmware
    In HD some videos will not adjust refresh rate.(a video with 23.976fps will not adjust refresh rate or resolution while a video with 24.000fps will adjust both and work fine)

    Common to all dtb:
    -ok CEC
    -wifi none
    -Hardware acceleration: DRM PRIME (when this is disabled it will use SW codec)
    -4k video not working
    -No render method to choose

    -ok remote works all
    -ok power on off
    -ok status led
    -lan detected with wrong ip

    -partial remote
    -ok lan

  • The Kodi log shows the TV doesn't offer 1080p/2160p @ 23.976 through EDID which is why that mode doesn't work correctly. The usual routine with EDID proglems is to check the cables and the ports on the TV (and software options on the TV) as different ports often have different capabilities (resulting in different EDID).

    The upstream kernel hardware decoder does not support 4K/H264; the original developer comment was "Amlogic had to go through various lengthy hacks to get it implemented so I've skipped it for now" .. and that was 2019 and nothing changed since. The box will play 1080p H264 and 4K HEVC so the main suggestion would be to re-rip/encode 4K H264 media files to 4K HEVC. There is no HDR to SDR conversion for UHD media in the upstream kernel.

    The vega-s95 device-tree in my test share has been tweaked to allow non-broadcom SDIO modules (e.g. Realtek) and the image has some RTL8189ES/FS drivers: which might allow WiFi to work. The remote can be (re)configured using the instructions in the wiki: - You can (re)use the "rc-videostrong-kii-pro" keymap which is already present in the image if that works.

    NB: The AMLGX image does not have feature parity with older LE releases and will not suit everyone's media collection. If it does that's great. If it doesn't .. it doesn't.

  • Here is my further investigation:

    WiFi is of no interest to me as it is a slow old version. I tested your firmware anyway and it detected WiFi and I was able to see my network and connect to it.
    There must have been a problem with my WiFi6 network. It allowed me to connect to 2 different AirMesh nodes having the same SSID and ended up with 2 IP addresses on the same SSID. This caused LibreELEC to crash and restart several times. It was only resolved when I deleted the connection and only connected to one of the SSIDs.

    I tested other 4K samples, this time only HEVC. None worked.

    I swapped the HDMI cable and port with the Nvidia Shield (This box adjusts the refresh rate for all videos including 23.976 fps) and the behavior is the same 23.976 fps won't change the TV FPS from 60 fps to 24 fps like the Shield does.

    My TV supports all HDR standards and I don't think it uses HDR to SDR unless it is something wrong with HDMI EDID. I don't see any setting at all about HDR in Player or System..

    My TV is Hisense (65H9G, 2020 Model)

  • My TV supports all HDR standards and I don't think it uses HDR to SDR unless it is something wrong with HDMI EDID. I don't see any setting at all about HDR in Player or System.

    The S905 (GXBB) does not support HDR output at all. Maybe the HEVC hardware acceleration works with 10 bpp, but the video is displayed with an incorrect color profile. As chewitt wrote earlier...

    There is no HDR to SDR conversion for UHD media in the upstream kernel.

    Without it, only "washed colors" will appear when HDR content is played, and the TV will never be informed that HDR content is being played. This is a hardware limitation of this SoC, unfortunately nothing can be done about it.

  • If Amlogic S905 can play 4k it will be helpful to point a video sample that works because so far while most of them play in stock Android in LibreELEC nothing that is 4k plays (8bit/10bit HDR/SDR HEVC/H264 ...)

    I did not see any 4k image at all (No washed or pixelate or...) I always see the Kodi screen.

    Audio ok
    TV changed display to 4k 50Hz (The video is 25FPS I guess 50Hz will do fine since it is multiple)
    No video displayed (I see the Kodi screen)

    Nothing plays (infinite progress circle)

    Nothing plays (may show infinite progress circle)

    Nothing plays (may show infinite progress circle)

    Audio ok
    TV changed display to 4k 60Hz
    No video displayed(show progress circle when reaches 100% it stops for one or two secconds)

    Audio ok
    No video

  • It's hard to comment on specific things without extracts/samples of your media to test locally and compare, but the main message (repeating myself) is that the AMLGX is not perfect and will not suit everyone's media collections, and if you're one of the users who it doesn't suit, there's not much we can do about that.