RPi4 testbuild with HDR support

  • The obvious solution is to re-encode legacy formats into modern formats so they are playable on the modern device.

  • The obvious solution is to re-encode legacy formats into modern formats so they are playable on the modern device.

    Though to be fair interlaced MPEG2 isn't a legacy format- it's a current broadcast format, as is DVD (there are still significant numbers of commercial releases that are DVD-only and don't include Blu-ray)

  • Though to be fair interlaced MPEG2 isn't a legacy format

  • Understood - and if it's all interlaced content - then that's pretty much everything I watch in Kodi!


    TV Headend h.264 1080i25 stuff is the bulk of my viewing on my Pi Kodi clients.


    (I'm not complaining - I know interlaced video is a pain and one that many wish would go away, but it hasn't yet..)

    Edited once, last by noggin ().

  • How "bad" is the dithering to 8-bit? I have a 10-bit FRC panel, so it's basically an 8-bit panel anyway, wondering if I'd even notice the difference, or if I should wait for the 4:2:2 mode/fix


    Currently I'm using an AMLogic device/build for my HDR files, but their SoCs don't support full color (0-255), which all my other devices on my receiver are set to, so I constantly need to switch my TV settings back and forth. Would love to just switch to my Pi 4 full time

  • I have used addon Audioprofile Add-on:Audio Profiles - Official Kodi Wiki

    I can now easily toggle between legacy .iso (with menu functionality), SD .mpg And .ts files and 1920x1080 .ts HD files.


    This addon should help others to setup profile for best performance for HD and UHD and another for SD then easily switch between formats. I found sometimes it required a double selection, but very versatile. Similarly good for switching easily between audio decoding formats

  • evanspae please don't re-post exact duplicates of your previous messages. This thread is for discussing details of HDR support on RPi4, so your general questions are off-topic in this thread. Please create a new thread in the "General" forum with your questions.


    so long,


    Hias

  • How "bad" is the dithering to 8-bit? I have a 10-bit FRC panel, so it's basically an 8-bit panel anyway, wondering if I'd even notice the difference, or if I should wait for the 4:2:2 mode/fix


    Currently I'm using an AMLogic device/build for my HDR files, but their SoCs don't support full color (0-255), which all my other devices on my receiver are set to, so I constantly need to switch my TV settings back and forth. Would love to just switch to my Pi 4 full time


    Do we know if the 10-bit to 8-bit conversion uses dithering rather than just truncation? Looking at the HLG HDR bars I ran the Rec 2020 tests on, the luminance sweep it looked like it was suffering from truncation rather than dither.


    I have a 10-bit native panel in my TV (not 8-bit + FRC)


    Out of interest why are you running 0-255 (or 1-254) rather than 16-235 - is it because one source is a games console ? In theory mixed 16-235 and 0/1-255/254 sources can co-exist if their InfoFrames correctly signal their range.


    I usually try and keep everything 16-235 for as long as possible to avoid multiple re-scales.

  • Do we know if the 10-bit to 8-bit conversion uses dithering rather than just truncation? Looking at the HLG HDR bars I ran the Rec 2020 tests on, the luminance sweep it looked like it was suffering from truncation rather than dither.

    I don't think the RPi4 even supports dithering.


    so long,


    Hias

  • The HVS can dither. It is enabled for 16 and 18-bit LCD displays.

    It hasn't been enabled for HDMI which is typically 24-bit to 24-bit

    (but 10-bit HEVC does change that).


    I'll see if I can spot a difference with it enabled.

    (although 10/12-bit output is starting to work).


  • D'oh, I didn't even think it would just truncate instead of dither. I guess I shall wait


    I run a mix of consoles and a gaming PC (and a NUC for my main LibreELEC player), so it's mostly been RGB full. My AMLogic boxes (S912 and S905X3) don't seem to trigger any sort of switch, and just washes out videos, so I need to manually switch TV modes when I use them

  • I run a mix of consoles and a gaming PC (and a NUC for my main LibreELEC player), so it's mostly been RGB full. My AMLogic boxes (S912 and S905X3) don't seem to trigger any sort of switch, and just washes out videos, so I need to manually switch TV modes when I use them

    Ah - I thought most platforms properly supported the Full/Limited Infoframe signalling these days. It was added to Intel HDMI drivers many years ago. (Ivy Bridge era or earlier ISTR)


    I run everything in Limited - as that's what SDR and HDR video (*) standards are based on - and they are my primary viewing on my main TV. I'm not convinced I can see the improvement with having 30 or so additional quantisation levels with a switch to full level for gaming (though Windows PC support for 16-235 can be 'interesting')


    (*) Dolby Vision Single layer can use 0-1023 levels with IPTPQc2 instead of YCbCr - but I'm not sure how that interacts with HDMI LLDV interconnects. (And it's a non-issue for the Pi 4B)