I dont have the Minix but should be the same as Ugoos for CE.
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In TV-led mode, the output is to a REAL TV-led,
i.e. your TV does processing like Oppo and Shield tv. -
we have full-fledged Cm 4.0 processing by means of your TV
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In LLDV mode, there will be only Cm 2.9 processing, cm4.0 is not processed.
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There are problems with FEL videos, they freeze when trying
to switch to another episode.
But, this player can become a really universal player, replace the FEL players
and you will get the correct processing in CM 4.0 mode. Which means there is no black cropping, there are no problems
with videos with a PQ of 1000 nits on brighter TVs.
If you have Ugoos Am6b plus or Minix U22x-j, then you are very lucky, if you don’t have it, then you know
what you need to do urgently if DV is important to you.
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Interesting, I never experience this. I even have the same movie you just showed and I can seek multiple times, switch between movies. Never crashes.
2.9 with TV-led works fine though, right?
I have a lot of problems with crash on seek, resume, etc.
Odd, it couldn’t be more stable here. Other than the TV, what would be different I wonder. I do have am6 plus, not the B revision. But I believe only the wifi card is different.
I use either http or nfs streaming when I watch something.
From Dolby on BluRay Authoring:
Dolby Vision Graphics Priority mode
"When graphics are the focus onscreen, it is desirable to program the UHD Blu-ray Disc Player to optimize the picture accordingly. Properties are now available to Blu-ray Disc Java (BD-J) programmers to explicitly switch between these modes.
Note: In HDMV mode, graphics priority is the default setting.
To maintain a consistent graphics and brightness level, a disc author can invoke Graphics Priority mode when graphics are present. The video is still rendered well, although certain advanced picture rendering technologies are disabled. Therefore, it is important to keep playback as the default Video Priority mode whenever graphics are not present, as well as for certain kinds of graphics, such as subtitles."
Please check page 16.
This was the key to understand and cross reference to the code.
The AMLogic code is setting this on each frame to graphics priority - (a bug in my opinion), quite possibly someone misunderstood it’s meaning/implication - as you say with all the talk on LLDV - the change was made in the code in 2020.
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I’m using http (and even plain text not https) with Apache httpd, and skipping chapters and backwards with FEL titles that were resumed seem to be working without issues for me. I wonder if the transfer protocol in use is the cause…
It’s set to 8-bit when you don’t use refresh change, because you’re most likely using 60hz (or 59.94hz) as default. 60hz 8-bit RGB is hitting the max bandwidth of HDMI 2.0b (593Mhz according to my HD Fury device), so that’s why it’s not getting set to 12-bit because it’s not possible with that HDMI standard.
As far as I know, for TV-led DV, the tunneling is always supposed to be 8-bit RGB, regardless of framerate. So setting to 12-bit RGB DV is incorrect, IIRC.
Also 8-bit RGB is equivalent to 4:2:2 12-bit for bandwidth. That’s what my TV is receiving with player-led at up to 60hz, for various devices I have so I’m pretty sure that’s correct for that mode.
so for now, use 20.4 ng-dv and the upgrade tar file you made?
CoreELEC team are working on a main line build and will be sure to share when ready.
For now those are the steps to try it.
Note: It is a test build so no surprise if something breaks!
I do hope they stick with it, more players in the space are always better and Sony always has an eye on quality for their products, I saw some mentions on DV bugs and some getting squashed - DV overall seems to be a mine field to step through for the consumer.
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Hopefully this community can come up with a solution for enthusiasts at least to enjoy DoVi content accurately. I’m guessing we’re getting close to that recommendation being LG WOLEDs paired with an S922X-J device.
Is there any risk to Amlogic discontinuing the S922X-J any time soon?
There were no problems on version 20.3. The nfs connection with nas was used.
I’ll check again today to see what might be causing the problem.
By the way, when the output image became with wrong colors in tv-led mode, usually green, it was due to confusion of rgb channels, in G channel instead of brightness Y goes channel CrCb, and in R gets brightness. That’s why the image is glitchy.
Not sure yet, but it is possible to get correct switching in rgb 444 8bit if there was a resolution or frequency change when switching, i.e. when I set 1920 by 1080 in the interface, the switching in tv-led was correct.
I need to double check this though.
@cpm How likely is it that your “Dolby Vision Graphics Priority mode” changes for the S922X-J will also work on other Amlogic device like the S928X-J & S905X4-K?
the same as you, some goes 12bit RGB, a few not, i set 1920x1080 not usefull, must set 8bit to work correctly in 8bit RGB, but then play hdr10 will also 8bit, i hope it can play DV 8BIT RGB, HDR 10 12BIT 444 automatic
All I can say is THANK YOU and wow! I just installed CPM’s 20.4 update on my Am6B+ box, (after first doing a fresh install of 20.4) and I tried my Apocolypse Now mkv Remux. It was such a giant improvement for me. It made me really happy, so much brighter and more vivid color. Haven’t seen anything look this good on my box.
My tv is an LG CX 77 and I am running the Ugoos box through a Pioneer VSX-LX505 and watching in filmaker mode. First I tried it in Player-Led (was the default in my backup) and I got a strange bug. On starting the movie (also quickly started Oblivion and got the same behavior) the video was tinted purple, but I hit the back button, to go back to Corelec menu (which was also purple tinted) while video was still playing, and kept hitting the back button until I got back to the movie and it fixed the color. After doing this I could watch the movie normally. It worked the same way on an Oblivion mkv. It seems like it has to do with the switching delay. Next I tried TV-LED and it worked flawlessly. I skipped around the movie and didn’t have any issues. Color was very vivid and bright, but maybe a little too bright and a little oversaturated, but it still looked really good. Even though it was a little too bright I think the TV-LED looked a fair bit better on the CX
I will test more stuff when I have more time, but this feels like a major step forward. What is the best way to dial down the brightness and saturation? I think I remember reading in this thread that I could tune it in the picture brightness settings in the player and then apply the settings for all movies. Will try that tomorrow.
I appreciate the hard work cpm feels like a breakthrough, at least for me on my TV.
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When the Amlogic-ng-dv is EOL, will this project continue in CE 21 ng?
I think there is a good chance, it is effectively just putting the DoVi proprietary “black box” into video priority mode (something documented by Dolby - it is not hidden).
To widen things even further it is also possible Realtek and others just have the same mistake, I would imagine they are all using the same Dolby reference implementation to build from - if they are not just given the library outright by Dolby and told the interfaces to use - a major one being getting the licence from the actual SoC. which I am sure they want to keep locked tight and obfuscated.
With all the cool and dedicated work done by the CoreELEC team this felt like the best solution to build my setup from - they had full Audio Pass Through and had worked out FEL (not withstanding someone had kind-of made FEL work earlier only to not tell anyone how they did it, not disclose the source and disappear!)
I hope the community can rally around CE even more than ever, it has strong foundation being built on - I just unlocked a cherry on the top for now 
Please note: the build I did is for G12 Family SoC only - mainly so I could concentrate on understanding AMLogics wrapper library for DoVi.
In time CoreELEC team will have a new versions on the main line to support more SoC as possible.
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Wow! Can you dev guys apply these great improvements to kodi linux upstream or other platform(android) as well?