Learning about Dolby Vision and CoreELEC development

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608

What are you talking about? I have no idea

609

Look at the “CHANGELOG” file in your build :wink:

610

I’m guessing because that is what is used in CE for some reason.

611

Yes, asked wrong person, sorry :slight_smile:
Perhaps @Vasco has the explanation…

612

Thnx for fixing blackscreen.

Can you tell me how to fix this for skin Aeon Nox Silvo?

Wich file to modify the skin?

613

Don’t know. I suppose it will be different for every skin.

For the default skin, I modified Custom_1109_TopBarOverlay.xml to shift the top bar down 8 pixels and also to disable the animation that slides the top bar up and away.

You will need to work it out yourself for other skins. The aim is to ensure nothing uses the top 8 lines in any way while a video is playing

614

Alright thank you i wil try

615

Good luck.

I found it easiest to first do on a copy of kodi on my computer. I used the instructions from https://kodi.wiki/view/HOW-TO:Estuary_Modification to be able to both see what xml file to initially look at and also to instantly reload the skin when I was testing changes.

616

Wich lines did you change in this file?

i cant find them

617

It was not rebranded. No cared till now.

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618

I kinda like it as even though it split you all started as brothers working on a great project.

619
620

Thank you very much!

May i assume that DV profile 5 isnt working?

621

Correct, that didn’t change with the recent builds.

Did have a look at the osmc code that was linked previously. Looks like all the work is being done using a lookup table for tonemapping to approximate what the result should be. Assuming that this is also responsible for the reshaping, but if that is the case or not isn’t clear given that not all the code is available to look at.

In any case, the reshaping step (the current blocker for profile 5) may be possible to approximate using a lookup table. Extracting the curve that should be followed from the DV metadata is already performed by libdovi so that isn’t a problem.

So the remaining sticking point seems to be how to implement that curve in the amlogic hardware. I’m guessing that is simplest to do via a custom LUT (I think per channel, i.e. luma and each chroma).

If it could be figured out how to set the coefficients of the LUT’s (in amcsc.c and/or set_hdr2_v0.c) into something meaningful (i.e., how to set the hex values of the LUT to produce a given curve) that would probably be enough to get some form of p5 working.

So if anyone wants to work that out…

622

I was the one that linked the code and recommended modules to use/change to get P5 to work. I did some testing but did not spent any time making sure all worked well with the reshaping and tonemapping quality since my goal was not to have P5 working as much as change the CE output on full DV-Std from ICtCp to YCbCr. From a pure code replacement/adjustment, I did get P5 to work even without the code that is private/secure but then again did not spent any time verifying how good or bad the image was.

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623

@R3S3T_9999
Been looking at some profile 5 rpu’s and have a few questions hoping you could help with

For profile 5 rpu’s, are the 2nd and 3rd (chroma) rpu_data_mapping curves always:

  1. num_pivots_minus2 = 0?
  2. pivots = [0, 1023] ?
  3. poly_order_minus1 = 0?

Also any chance of a collection of a handful of representative profile 5 rpu’s to examine to investigate possible methods of reshaping?

Thanks

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624

I dont know much about how the profile 5 DV color reshaping works, Quietvoid or Rainbaby could tell you a lot more but AFAIK, there are two kinds: static and dynamic reshaping… I did some samples here, I hope this still can help you.

1-Dolby Encoding Engine (DEE): Dynamic reshaping. All streaming services except Apple seem to be using this. The colors stay identical to the HDR master.

2- Resolve: Static reshaping: No one seems to be using that. The colors stay identical to the HDR master.

3- Anything from Apple seems to have the same static color reshaping for all its content. This includes their original tvshows/movies and all the apple non-original movies on iTunes. Their method totally destruct the original HDR Master colors. see: unknown | Slowpoke Pics

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625

@doppingkoala where i can find the setting to turn of DV?

626

Nothing exposed in the gui. Use

echo N > /sys/module/amvideo/parameters/inject_osd_metadata

to disable DV

627

https://discourse.csmc.x/t/testing-vero-v-dolby-vision-tv-led-support/108393

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