No Upscaling With 4K @ 60fps Support?

  • I did a few searches and couldn't find anything specially addressing my issue so here goes...

    I currently have the display setup on a rpi4 for 4k@60 via a config.txt override and thats fine for 4k movies. However if I play 1080p videos kodi upscales them to 4k too when I just want to display them in their native resolution and let my tv handle the upscaling instead.

    I've tried changing the display output to 1080p for kodi in case it might switch to 4k for 4k video but it doesnt like it, I assume because I have overidden defaults in the config.txt for 60 fps @ 4k output and thats being forced on it now.

    Is there a way to have all video resolution output aligned to the video file for kodi output whilst supporting 60 fps?

  • Whitelisting would be great if it worked properly, for some reason 1080p mkvs get upscaled even if I whitelist all 1080p modes...

    If then then go to manually set resolution of them on playback they are initially listed as 120hz which I guess falls beyond a frequency supported on a rpi and drop through to upscaling. If Inset them to say 30hz then great, no upscaling.

    I'm only guessing here but it looks like there needs to fallback mode per resolution for any frequencies or something.

    Worth rasing with the kodi devs I guess!?

  • So after a sleep and going through the 4k hdr recommendations again (here: https://wiki.libreelec.tv/configuration/4k-hdr) and tweaking from there I have (touch wood) a working setup. There were a few issues I had to work through to sort it, as follows:
    - switching straight from 4k@60 to 1080p@60 for the GUI didn't work, going via 30fps got me to 1080p@60 though
    - 4k@23 needed removing from the whitelist as my lg oled doesnt like the format, the "allow double refresh rates" option was needed, resulting in output from kodi of 4k@59 for those video files

    I'm guessing now any issues I have with video format support will need more whilelist removal, but until I hit issues what I have is good!

    I hope this helps someone, for me being pointed at the whitelist option started the ball rolling, seeing the above listed page on hdr would have gotten me there even quicker 👍

  • Ok, another issue relating to whitelists now, a small percentage of my 1080p videos which are h265 (hevc) don't seem to render ok for my lg oled due to being whitelisted. Previously before I moved to a 4k tv my 1080p content was all transcoded and my old tv was happy, now I have mixed res video and want to upscale on the tv I have issues...

    Is there anyway to force transcoding video formats but leaving the resolution alone? Output as h264 60fps for example but leave upscaling for for the receiving end?

    Do I now need to be careful about what the encoding is for video files so my tv supports playback because of whitelisting, where I didnt concern myself before?

    Whitelisting for resolution alteration only would be nice :)

  • I'm using an RPi5 with an LG 4K OLED set. I don't see these issues. I also didn't see them in the past with an RPi4 either. However I never enabled 4K@60 modes because I have no 4K@60 media other than a few test files, and I suspect that 99% of people enabling 4K@60 modes "because, more is better, no?" similarly have no actual need to enable them. I also have all the HDMI sockets on the LG enabled for deep-colour modes (which changes their HDMI capabilities) and I am only using 4K60 certified cables between RPi and AVR, and AVR and TV. I also follow the configuration recommended in the 4K-HDR wiki article (which I wrote).

    Some of the items in your initial descriptions read like "user didn't read the manual" issues. Others sound like insufficient PSU and/or cables - all of which are helped by NOT enabling 4K60 modes and using the right HDMI ports (they are not all equal).

    NB: We do occasionally see users complaining about media with weird encodings that an RPi board will not play, but that's usually media they stole/torrented so isn't something we care about investigating. If it's only a handful of own-source files that cause issues you can always use tools like Handbrake to fix the weird encoding and make things playable.