HDR, 4K questions

  • Hello,

    I got a new beamer, JVC NZ7, which can also tonemap the HDR. So I would finally like to watch some movies in HDR... previously never really did much with it, except that I've seen it washed out and let it be.

    Now, I would like my beamer to tell me it's HDR material and show it accordingly. However, it doesn't... all I get is a stuttery playback and SDR.

    So, I have two questions:

    1) is my "old" player with i3-6320 CPU still enough to play back 4K HEVC (H.265) 10Bit HDR+, or does it stutter because it doesn't have enough power?

    2) should I be able to play it back so, that my beamer tone maps? (same like my AVR is doing audio passthrough, but with beamer, and "hdr passthrough")?

    Hardware update is possible, if needed and would fix the problem.

  • In the meantime my own research tells me that my CPU is too weak for H.265/10bit. So I am going to get an 12th Gen i3. That should be enough to play anything I throw at it.

    However, this doesn't answer my 2nd question: will Kodi then pass HDR to the beamer and not tonemap itself? I just want 1:1 signal to the beamer, nothing more, nothing less. Is that possible?

  • Current nightly builds for x86-64 (Generic builds) are supporting HDR and it is sent to the display device so that any tone mapping would be done there. The current stable releases for x86-64 do their own tone mapping, which is not what you're looking for.

    I also looked up your CPU - you are right. It's from 2015 and lacks the acceleration hardware needed for h.265. It depends on your budget and what else you need, but I am using a relatively low power Gemini Lake cpu and that is OK with 4k60 using h.256/HEVC, so there's no strict requirement to go for the latest silicon. One thing to watch out for is how the HDMI output is handled. Some NUCs, for example, have used an additional chip in the display driver circuit (known as an LSPCON chip) to allow the port on the box to reach HDMI 2.x standards. While they can work, success with LibreELEC is more likely if you can verify that your chosen solution does not use an LSPCON chip.

  • Kodi has no support for tonemapping and is unlikely to gain that capability anytime soon. Most hardware Kodi currently runs on either lacks the specialist image manipulation capabilities to do on-the-fly tonemapping, or the hardware can do it, but support hasn't been implemented in the Linux kernel and drivers yet; and hence there's no need (and not much point) trying to support it right now.

    In simplistic terms: Kodi simply outputs video with an appropriate resolution, colour depth, colour-space, and HDR flagging as detected from the media being played and within the constraints of what the hardware (HTPC) can output. As not all hardware supports all combinations (read from the HDMI EDID data) Kodi will sometimes output in a higher bit-depth or nearest colour-space from possible output formats. It's then up to the display device (Monitor/TV/Beamer) to figure out how to display that combination.

  • Kodi has no support for tonemapping and is unlikely to gain that capability anytime soon. Most hardware Kodi currently runs on either lacks the specialist image manipulation capabilities to do on-the-fly tonemapping, or the hardware can do it, but support hasn't been implemented in the Linux kernel and drivers yet; and hence there's no need (and not much point) trying to support it right now.

    In simplistic terms: Kodi simply outputs video with an appropriate resolution, colour depth, colour-space, and HDR flagging as detected from the media being played and within the constraints of what the hardware (HTPC) can output. As not all hardware supports all combinations (read from the HDMI EDID data) Kodi will sometimes output in a higher bit-depth or nearest colour-space from possible output formats. It's then up to the display device (Monitor/TV/Beamer) to figure out how to display that combination.

    Today I found out that my Rpi4 can play 4k hdr10 file, but with washed-out colors... while my Huavei laptop, Ryzen 5 3500u, running Kubuntu, can play the same file just perfect (with vlc and Kodi), with HW acceleration and very nice colors? Why is that? why Rpi4 can not do it?

  • Today I found out that my Rpi4 can play 4k hdr10 file, but with washed-out colors... while my Huavei laptop, Ryzen 5 3500u, running Kubuntu, can play the same file just perfect (with vlc and Kodi), with HW acceleration and very nice colors? Why is that? why Rpi4 can not do it?

    Does your TV support HDR and BT.2020?

    If not that's expected as the RPi can't tonemap HDR videos to SDR which vlc on your laptop probably does.

    so long,

    Hias

  • I haven’t used a RPI4. However I have a JVC projector and a lumagen. The intel Nuc 12 works fine with HDR. However will not correctly output HDR10+ files. Also will not output 4k60 HDR content at the moment either.

    I’m currently building a Ryzen system to compare.

  • Does your TV support HDR and BT.2020?

    If not that's expected as the RPi can't tonemap HDR videos to SDR which vlc on your laptop probably does.

    so long,

    Hias

    Yes. The TV is Philips 4K Android TV and with Kodi installed on it the same file plays just fine. Only the Rpi4 has problem.

  • Yes. The TV is Philips 4K Android TV and with Kodi installed on it the same file plays just fine. Only the Rpi4 has problem.

    Please provide a debug log, the output of modetest | pastebinit while playing a HDR file and mediainfo output of the file (mediainfo is available in the multimedia tools addon).

    Please provide a full debug log.

    How to post a log (wiki)

    1. Enable debugging in Settings>System Settings>Logging
    2. Restart Kodi
    3. Replicate the problem
    4. Generate a log URL (do not post/upload logs to the forum)

    use "Settings > LibreELEC > System > Paste system logs" or run "pastekodi" over SSH, then post the URL link

    so long,

    Hias