Did some tests on my Panasonic LZ1500. Differences are subtle but BT709 flag gives the skin tone more natural colour. BT2020 seems a little pale an monotonal.
cool, so three different TV and three different results - albeit from subjective tests, so one size does not fit all and may help explain why some blu-ray players set and others did not.
Do you think it’s possible to turn this into a menu item since the result varies from TV to TV? It would make it much easier for users to decide.
Which build are you running?
I ve just installed latest 20.5 nightly and was playing around with settings. Player process OSD only displays unknown for bit depth, etc. I used dispinfo and found a tool on TV itself to check device info. With bit depth on auto and TV-led I get 12 bit for everything, DV, HDR10+, HDR10 and SDR. For DV content its 12 bit + rgb full, idk I tried forcing it to 8 bit like it is supposed to be, can’t say that I notice the difference in picture (was mainly checking Parasite 2019, which is a FEL title). Player-led triggers 10 bit and broken colors, forcing to 12 bit fixes colors, but didn’t bother to play with it as much.
One you may have, just to see if there is a diff in something more static is The Batman - the opening Titles in red: WB, The Batman etc.
The bt.709 is a bit brighter (a shade more towards orange in presentation),
The bt.2020 is darker in comparison for me.
FYI, need to let it play as will not change when paused, but can do from a ssh session quickly flipping between the Y and N.
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I will try later on my Sony Tv’s
Nice find!
Have not dug into what that does but been playing with the value.
Currently landed on quite a bigger number which seems better to me, more stable playback and seeking.
echo 512 > /sys/module/amvdec_h265/parameters/dynamic_buf_num_margin
This is on the latest 20.5 nightly 29
1917: the 2 soldiers walking in the trench.
Braveheart: the princess talking to the king at almost 5/6 minutes
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Absolutely no difference. I did notice before that it only changes while playing. I also tried pausing, changing the setting than playing but no difference.
Tried; Batman, 1917, Goonies, Migration.
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Is your preference toward the BT2020 setting possibly mostly related to it being more saturated?
If so, I’d assume CoreELEC signaling none, and the TV defaulting to Rec709 would be the more accurate (saturation).
I would not say it is more saturated, in many scenes the colour is less “saturated” or maybe put more accurately I would say less condensed, with more spread, it is more like it opens up the colours particularly at the bright end for me so the “air” or realism is slightly heightened mainly around highlights - maybe you could say it feels a bit more “HDR” if you will.
Not saying it is right or wrong just I find it more realistic and engaging - I do understand the natural propensity of people to be attracted to more saturation - I am pretty certain that is not the case here - but I could be fooling myself!
I dare say my E8’s colorimetry abilities are actually not that high - would like to see this on a 2nd or even 3rd gen QD-OLED panel where I suspect it would be more obvious (if processing the same way).
Should also reiterate it is only a very limited difference a more casual look and not side by side would not really pick up on it - I only went back to add the flag switching ability because I felt something was missing after a few hours compared to before and wanted to see if that was the cause - I was surprised to actually see it made a difference given the nature of Dolby Vision IPT but looks like the TV is mapping the colour space after or during the processing according to the flag,
As to the flag bt.2020 if it is not set the AMLogic code is falling back to set bt.709 explicitly instead (as defined by the spec for UHD res - see pdf shared earlier) - I do not know what the TV actually gets but no reason to suspect that flag is not passed to the TV as in both cases they are explicitly set.
As mentioned I also had my own private test build where I zero’d out the colorimetry bits and then got “Default” on Kodi - it is unknown what that meant to the TV but looked like the same results as with explicit bt.709 to me. (this may make sense if the TV is also following the same fallback logic and using the UHD res)
P.S. For what it is worth I have always had a keen interest in photography from film to digital - and my father was an art and design lead so I guess I know my fair share about colour rendition and tones.- I have also been a programmer for 40+ years now (pretending to be an architect more now - but still a dev at heart) and know something of the computer graphics world too.
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Made an interesting observation for my 12 bit DV problem. I copied a P5 movie into storage of mine am6b+ and I get 8 bit colors from it, the same movie via PlexMod4Kodi is giving 12 bit. Well, I guess, I should figure out, how to properly use Kodi without pm4k and test other titles.
Upd: Player-led works from internal too.
Yeah, I tried a Plex addon in the past and dv was completely broken. Never bothered with it again. I have a linux server and share my HDD with nfs and been pretty happy with it.
Plex add on is fine. Been using it since 20.3-ng-dv. No problems with DV.
It just passes the stream to the internal player anyway.
I think I used this, p5 dv was broken with it. dontpanickodi/matrix/script.plexmod at master · pannal/dontpanickodi (github.com)
Well, I shared my movies folder via smb, same movies trigger 12 bit via pm4k and 8 bit on kodi with smb. Idk about picture quality, cause my remote died mid testing, but for certain player-led doesnt work via plex mod (triggers 10 bit with broken colors).
I d love for plexmod to work correctly, as I prefer its interface (while still worse, than native android app), but picture quality above all I guess…
I use that same mod, DV5 is fine.
All PlexMod does is pass the stream onto the internal player. If there’s an issue with DV/HDR etc, that’s the underlying player.
If there are differing outcomes, that could be another issue. But PlexMod has nothing to do with Playerled DV and you can post here if you want to verify:
I run PM4K on my Zidoo with player led DV. It’s fine.
If it’s not appropriate in CE, that doesn’t mean it’s PlexMod’s issue.
You could also use PlexKodiConnect and load your content into Kodi natively. Could even use path substitution to directly play from your SMB.
I dont say, that its necessarily pm4k issue, I just report my experience, in case someone faces the same issues as me/someone smart can figure out what is the problem.
And PlexKodiConnect sounds interesting, I’ll look into it.
Are your moddings from your latest build integrated into the latest nightly? Or are they not needed anymore?
Edit: just installed latest nightly and tested it out with my Sony TV (A95L 2023 QD OLED). Colors and brightness looks the same and my tv shows BT2020 when flag is enabled. When it is disabled, no colorspace is shown on the info screen. With my Zidoo it showed BT2020, too. I think the BT2020 flag enabled is the better variant, as my tv shows no colorspace at all if the flag is not set. Picturewise it makes no difference,but it just seems wrong if no colorspace is shown on the info.
