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More => Old Versions => JRiver Media Center 27 for Windows => Topic started by: fitbrit on October 10, 2020, 09:19:23 pm

Title: HDR content shows as just a green screen on SDR TV
Post by: fitbrit on October 10, 2020, 09:19:23 pm
On a 1080p Plasma screen, with ROHQ and MadVR set to convert HDR to SDR, I get a green screen only on HDR videos. If I play a 4K UHD bluray, the non-HDR menu elements play properly. But the menu elements are overlaid on an HDR picture, which also shows as just plain, uniform green.
I've set up a non HDR 1080p screen many a time with MadVR to downscale a 4K image and convert HDR to SDR, so I'm wondering whether this is a recent bug, some kind of backwards compatibility thing with plasma technology, or something else altogether.
Title: Re: HDR content shows as just a green screen on SDR TV
Post by: tij on October 11, 2020, 12:25:23 pm
HD content plays fine?

Did you try RO Standard on HDR stuff, does that work?

Might be stupid question, but are you downscaling to 1080p or outputting 4k to your TV?

Also, are using Windowed D3D11 or exclusive screen mode?
Title: Re: HDR content shows as just a green screen on SDR TV
Post by: fitbrit on October 11, 2020, 01:16:22 pm
Yes 1080p is fine.
4K is being downscaled from MC’s custom settings. The disc’s splashscreen and full screen menus are not HDR and are being played correctly. On some screens a background video is HDR and showing as solid green, but the menu selection for episodes is shown correctly as an overlay and is presumably not HDR.
Audio plays fine.
Not using exclusive mode.
Did not try RO standard because the goal was to show how well MC colour tone-maps using MadVR (default MC implementation of MadVR).
Title: Re: HDR content shows as just a green screen on SDR TV
Post by: RoderickGI on October 11, 2020, 05:07:41 pm
When I read green screen I automatically think "bad cable"... but green HDR background behind a non-HDR overlay? Hmmmm.

I guess if the cable is bandwidth limited, that could cause the issue. Otherwise, I would be going with Plasma screen compatibility as the most likely cause. You mention backwards compatibility. Is this an old Plasma screen?
Title: Re: HDR content shows as just a green screen on SDR TV
Post by: tij on October 11, 2020, 09:51:43 pm
Yes 1080p is fine.
4K is being downscaled from MC’s custom settings. The disc’s splashscreen and full screen menus are not HDR and are being played correctly. On some screens a background video is HDR and showing as solid green, but the menu selection for episodes is shown correctly as an overlay and is presumably not HDR.
Audio plays fine.
Not using exclusive mode.
Did not try RO standard because the goal was to show how well MC colour tone-maps using MadVR (default MC implementation of MadVR).

Try RO Standard ... just to see if it works

Also ... when playing HDR movie with green screen (not BD menus) ... does MadVR OSD shows up when you press Ctr+J ... if it does, could you post screenshot of that OSD (the info there could be really useful in troubleshooting)
Title: Re: HDR content shows as just a green screen on SDR TV
Post by: fitbrit on October 12, 2020, 01:07:49 pm
When I read green screen I automatically think "bad cable"... but green HDR background behind a non-HDR overlay? Hmmmm.

I guess if the cable is bandwidth limited, that could cause the issue. Otherwise, I would be going with Plasma screen compatibility as the most likely cause. You mention backwards compatibility. Is this an old Plasma screen?

It could be the cable, possibly. The person whom I was helping intended to run the system headless, controlling audio playback from a laptop. However, I was keen to show him the tone-mapped and downscaled picture from a 4K BluRay rip, so he connected the TV using a cable he hastily found. So, it definitely wasn't vetted to be a high-speed cable by any means. But again, just showing a partial picture is really weird. It is an old Panasonic plasma screen - but at this point, aren't all plasmas old now? By compatibility, I meant that back in the day, some plasmas had unusual native resolutions and did some odd scaling to present the 720p, 1080i and 1080p signals.

Title: Re: HDR content shows as just a green screen on SDR TV
Post by: fitbrit on October 12, 2020, 01:11:22 pm
Try RO Standard ... just to see if it works

Also ... when playing HDR movie with green screen (not BD menus) ... does MadVR OSD shows up when you press Ctr+J ... if it does, could you post screenshot of that OSD (the info there could be really useful in troubleshooting)

Thanks for the responses Rod and Tij.

I will get the opportunity to connect to this system again in about a week. I'll bump the thread then.
I'll try ROStd and the MadVR overlay.
I do think the stats were visible in the mixed video with green screen and non-HDR menus; I'll try again with a non-menu mkv HDR rip.

Thanks for the suggestions.
Title: Re: HDR content shows as just a green screen on SDR TV
Post by: Hendrik on October 12, 2020, 01:20:50 pm
A video showing entirely green has typically nothing to do with the output, and more with the decoding, even more so if an overlay on top is working. If its using hardware decoding, there is a good chance the GPU is failing at it, so try without hardware decoding. And of course updating graphics drivers.
Title: Re: HDR content shows as just a green screen on SDR TV
Post by: fitbrit on October 12, 2020, 01:32:19 pm
A video showing entirely green has typically nothing to do with the output, and more with the decoding, even more so if an overlay on top is working. If its using hardware decoding, there is a good chance the GPU is failing at it, so try without hardware decoding. And of course updating graphics drivers.

Thanks, Hendrik.
The thing is that the system was working perfectly for HDR before I shipped it out last week. I wonder if a Windows update has happened in the meantime, requiring an AMD update (using a Ryzen 5 3400G APU). Will check it out.
Title: Re: HDR content shows as just a green screen on SDR TV
Post by: tij on October 12, 2020, 08:00:02 pm
A video showing entirely green has typically nothing to do with the output, and more with the decoding, even more so if an overlay on top is working. If its using hardware decoding, there is a good chance the GPU is failing at it, so try without hardware decoding. And of course updating graphics drivers.
Try RO Standard ... if that works - it eliminates possibility of HW decoding ... and points to problem with MadVR settings

PS. ppl have lots of problems with 3D on  Windiws 10 v2004 on AMD and Intel GPU. Maybe that update broke h.265 decoding too (though i have not seen any reports on that)