USB to HDMI adapter with 4K UHD @30fps support - supported by LibreELEC?

  • Hi,

    I have a mini PC (PiPO X7) that is running LibreELEC.

    Unfortunately this box does not have 4K UHD support. (No 4k UHD options in whitelist and LibreELEC display resolution, maximum resolution is 1080p)

    I found some USB to HDMI adapters in Amazon, some of them claiming to support 4K UHD.

    Anyone used these adapters before? Do they work with LibreELEC?

    Or should I buy a new device instead?

    Edit: I just noticed the cheap adapters are all USB-C to HDMI.

    My box does not have USB-C port, bummer.

    There are adapters support USB to HDMI, but they are very expensive (like this one in Amazon), might even cost more than a brand new SBC.

    Maybe I can use a USB to USB-C adapter combined with USB-C to HDMI adapter. But it feels like a very bad idea.

    Edited once, last by Reguna (May 7, 2022 at 12:37 PM).

  • I've never seen such an adapter on this forum. So I bet there is no Linux driver for this, and therefore no LE support.

    If you want to upgrade to 4K, buy a new box. RPi 4 is among the cheapest options.

  • Also, according to Google, the PiPO X7 has a very low power Atom CPU from 2014 (Atom Z3736F) - probably very inadequate for 4K decoding from h.264 format, and a lot of 4K content uses h.265 which would need some hardware acceleration in the CPU (not present in this old Atom). I would also recommend a much newer device if you are serious about playing 4k content.

    https://ark.intel.com/content/www/us…o-2-16-ghz.html

  • Also, according to Google, the PiPO X7 has a very low power Atom CPU from 2014 (Atom Z3736F) - probably very inadequate for 4K decoding from h.264 format, and a lot of 4K content uses h.265 which would need some hardware acceleration in the CPU (not present in this old Atom). I would also recommend a much newer device if you are serious about playing 4k content.

    https://ark.intel.com/content/www/us…o-2-16-ghz.html

    Direct streaming requires CPU power too? Sorry I am new to this

    (My 4k UHD movies are mostly h.264)

  • Direct streaming requires CPU power too? Sorry I am new to this

    (My 4k UHD movies are mostly h.264)

    Nothing is free, and something still has to decode the video and audio data and store it in a frame buffer and display it on the screen...

    With a 4k image there are four times as many pixels to generate when decoding the data. Even with compression in the original data, there will still be more data to decode in the source data stream than for a 1080p file. And as mentioned, that Atom processor is very low power, even by Atom standards (it's also 8 years old). Regardless of that, you still have the problem of needing a driver for a suitable USB display adaptor - I very much doubt that exists in an easy to use form, and even if it existed, for LibreELEC you'd possibly have to build your own binary. In my view, it's just not worth it, given that there are other ready build solutions available.

    As mentioned above, a Raspberry Pi 4 could easily do it. If you're only using h.264, you could also look at some other second-hand Intel solutions. For example, a Celeron N3060 can manage 4k @23.967 (and probably at 30 fps as well) with h.264, but absolutely cannot with h.265 since it lacks the hardware acceleration. Newer Intel CPUs (the Gemini Lake platform for example) are relatively affordable and can play full 4k UHD blu-ray rips without issue.

  • Even if there exists a Linux driver, the adapter still wouldn't work for your setup. The adapter must grab a 4K stream from somewhere, but your graphics card (Atom processor) can max. deliver HD. It's just an adapter, not a graphics card.