For anyone interested, we solved it with a plugin 
All great info, thank you. And you’re right, not all HDMI splitters and audio extractors work with odd timings…but luckily all the ones that work with odd retro gaming signals work with these. I appreciate the reminder though and I’ll make sure to mention that in the video.
I appreciate the detailed response Hias. I’ll see if I can come up with something to simplify things for installation before making the video.
Any suggestions for audio? Should I just try my best to create an EDID that also supports all audio modes? Then also assign it to both HDMI outputs?
I respectfully disagree. Adding a setting buried in an expert menu that's only going to be used by people who understand what they're trying to do (CRT & Projector use) isn't something that's going to cause problems for the average user.
Also, editing the EDID is a giant pain that most people aren't going to bother to do. Even people who'd like to make this work.
Please remember, I'm not just an end user asking for some random feature - I've spent over the last decade working with developers all over the world on retro gaming and retro video devices. I've had hundreds of conversations just like this one with dev's much smarter than me that just don't "get it". Eventually, some go to RetroRGB's site/channels and realize I actually know what I'm talking about, but most dismiss me just like you're doing.
So hopefully HiassofT will take me seriously and consider adding this even just to a private build I can test. If it works as well as I think, maybe these options can be added behind an "unsupported video modes" toggle or something?
HiassofT Is it possible to just add the 4:3 resolutions and 72Hz / 96Hz refresh rates to the whitelist of a nightly build? I'll happily throw a $100 sponsorship just to be able to test this feature and see if it works as good as I think it would.
I promise, I'm not asking just for my single use case! This would actually be a pretty big deal, as all the people doing the same thing these days either need to hunt down old video processors, or spend around $400 on modern scalers. I'll be doing a video similar to this one for the stuff I'm testing here:
While the main reason for asking is ease of use, I've also been having audio issues this whole time. Using the second HDMI port as audio-out almost never works and I even sometimes have issues with the audio on the main HDMI-out that's connected to an HDMI DAC. I don't have those issues without custom EDID's.
Here's the 4:3 resolutions people would need, with 640x480 and 1440x1080 being the most important:
Setup a whitelist and enable "Adjust refresh rate" - see eg here https://wiki.libreelec.tv/configuration/4k-hdr (it applies to non-4k setups as well).
Also enable "allow double refresh rates" and/or "Allow 3:2 pulldown" if needed - this can help kodi picking the correct resolution if it doesn't have an exact match (but has 2 or 3:2 times the refresh rate).
If kodi can't find any matching resolution/refresh rate it will use the one that you configured for the GUI.
so long,
Hias
Thanks Hias, I'll spend some time this weekend trying to make this work. Both this and the other question you helped with will be part of a pretty fun video I'm working on...so your time here isn't just helping me, it's helping all my fellow CRT/Projector nerds who'll see it. I'll definitely shout you out in the video!
...also, it seems 640x480 @ 24Hz is too low of a clock speed for HDMI hardware to recognize, the same way 320x240@60 is too low. That's why retro gamers need to use something like 1920x240 to send "240p" over HDMI for CRT use. But I have a few ideas for that too - I'll try them all and report back.
Is it possible to configure Kodi / LibreElec via a RPi 4/5 to automatically change its output to whatever matches the file being played? Basically, if the file is 1280x720@60Hz, the output would switch to match when the file is launched, then default back to a basic resolution (480p, 1080p?) when it's done?
I think this could be done manually if I was able to create an EDID for each individual resolution per this thread: [RPi] Adding Custom Refresh Rates
...but it's tricky to make an EDID file for resolutions like 640x480 @ 24Hz created from inverse telecined DVD's, which is a file type more common then you'd expect.
This would be really helpful for going into video processors or displays that have scaling features not available in Kodi, so we can send them the original file with no transcoding done. "Source Direct" players are definitely for video enthusiasts, but they're very hard to find and Kodi already does such an awesome job with tons of different file types.
Yup, the problem was me - All fixed. I attached what I created, in case anyone else wants to try. Here's basic instructions, but I'll have a video soon showing both how to do this, as well as why it's such a big deal for PC CRT monitor and projector users:
- Connect a working LibreElec/Kodi RPi setup to your network
- Go to Settings \ LibreElec \ Services and enable SSH
- Go to Settings \ System Info \ Summary to get your IP address
- Open a command prompt window, then ssh into the Pi via command line by typing: ssh root@ipaddress
- Enter the password
- Type "getedid create" and hit enter. LEAVE THE COMMAND WINDOW OPEN
- Use Filezilla (or your preferred software) to log in via SFTP-SSH
- Back out one directory, then navigate to /storage/.config/firmware/edid
- Delete the edid-HDMI-A-1.bin file (overwrite sometimes has issues, just delete it)
- Copy the unzipped edid-HDMI-A-1.bin file attached to this post to the directory
- Close filezilla
- Go back to the command prompt
- type "create-edid-cpio" and hit enter
- type "reboot" and hit enter
This will set the default resolution to 640x480 @ 60Hz, which basically everything should be compatible with. Then, change some Kodi settings:
- Settings \ Player \ Videos \ Adjust display refresh rate = Always
- Settings \ Player \ Sync Playback to display = Confirm it's OFF
(if you can't see these options, change the settings view in the bottom-left to "expert"
Then back out to:
- Settings \ System \ Display = Select the preferred resolution and refresh rate.
If you ever need to revert the RPi, you can just SSH back in and run "getedid delete"
I still need to test audio and a few other things, but that should be enough to get my fellow CRT nerds up and running!
That definitely worked and I confirmed that Kodi is even sending 24p sources in a proper cadence - Thank you very much!
I'm having an issue creating an EDID that supports multiple resolutions though. I'll keep trying and recruit some friends that have more experience in this, but at the moment, when I switch to a resolution that isn't 640x480, the screen gets cut off and the Pi is still actually outputting 640x480. I assume this is a mistake in my EDID creation, but I wanted to mention it, in case it's a Kodi-specific thing.
I'm looking to add both 640x480 and 1440x1080 resolutions at 72Hz & 96Hz each to my setup, for proper 24p cadence on my display. I tried adding just one resolution at a time in both cmdline.txt and config.txt and I can't see those as an option to whitelist. Can anyone please let me know how to add those as an option?
