Learning about Dolby Vision and CoreELEC development

Thanks for the samples. All show that the two chroma channels always have a linear reshaping.


The reshaping for the apple p5 samples is also linear for the luma channel. Essentially it only converts from valid limited range values, (64-940 for luma and 64-960 for the chroma channels) into full range (which p5 is) as shown below.

edit: do you have any examples for apple p5 that are more extreme / obvious to test with? There are some flags about full / limited range in the metadata that could be played with to see if anything interesting happens.

Any ATV webdl has a color shift caused by the static reshaping metadata.
see quietvoid comment on this:
https://forum.makemkv.com/forum/viewtopic.php?p=121576#p121576

Reading all of this made my brain hurt, i have one question about all of this. My tv is hdr10+ capable and is not having dv support, plus my tv box is a95x that have s905x3 chip inside. With all that said, will using all this enable me to convert dv file to play in hdr or hdr10+. Since right now using latest NO nightly i can play some hybrid dv/hdr10+ in hdr10+ mode but if file have only dv then colors are all green and purple

Ps
can i get instructions how to get this working with latest NO nightly, or do i need to use pre-made build

No
You need a Dolby Vision capable TV/Monitor for this Build

The whole purpose of this Test Build is to prove
Dolby Vision playback on non licensed amlogic SoC

Can confirm the Excellent work of Doppingkoala!!!

On numerous nonlicensed Boxes like Hk1x4 S905X4, Tanix Tx5 Plus Deluxe S905X3 etc…

Oh, to bad i thought that this can be used to play dv content on non dv display

Seems that my post yesterday was ill received so it’s better to just start over. Stay on topic, this is still a moderated zone.

Thank you. I didn’t notice any visibly raised black levels anywhere, everything looked good to me. Is it possible to have this data “follow” the vertical shift so it’s not even potentially an issue? Zoom does not seem to affect the image despite also moving the pixels around, so I would think Shift wouldn’t either. In other words if I Zoom the image down so it is rendered smaller in the middle of the frame, it seems to be displaying correctly with no artifacts, so the DV mapping seems to be correctly “following” the image pixels to their new positions when Zoomed, but not when Shifted. Sorry I don’t have any tech knowledge on this stuff!

Probably doable, but it seems a very niche problem that I don’t have. So probably won’t happen.

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I noticed the overlay where the image was shifted happens not just in your build but even in the official Kodi build on a Dolbyvision-licensed Android TV device, but only on some files. So I guess this is a bug I need to report elsewhere to main devs. Thanks.

Last night I was getting the quick freezes every couple minutes on an ep of Star Wars Skeleton Crew. Went to do it again today to get a dmesg log and naturally it didn’t do it while I was watching…

@doppingkoala I’m thinking of hooking up non DV licensed Vontar X4 box (S905X4) on my parents LG OLED, will your CE version playback DV? thinking of using your image or CE 21/22 depending on if this can playback DV or not. :slight_smile:

If the tv supports tv-led DV, yes - bar FEL (played back as MEL and unlikely to ever change) and p5 (may get added).

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thank you, great, do I need to add dovi.ko or works without it? will it only work with CE NG going forward? :slight_smile:

Works without.


Can work with any version, had it going with the NO builds before. Not likely to bother redoing that though until I have a reason to upgrade and the NO builds are a lot less buggy.

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Thank you, good to know, wow for those less nerdy (read parents) these cheap boxes (50 euro) are great if you have TV med DV, either run CE direct on emmc (deletes Android) or in my case slimBOXtv as they use IPTV and SmartTube, CE on microSD, I tried to move data storage to emmc like on the Homatics boxes but would not work unfortunately.

A post was merged into an existing topic: Help, support CPM build

@doppingkoala I installed your build and tried some 4K DV, Lord of The Rings Extended 4K DV remux (Framestor) and unfortunately it’s stuttering a lot and Gemini Man (60fps) is broken haha, works great on Ugoos/Homatics box.

I’m running CE on microSD card but should work fine? will try normal CE 21.2 and see.

  1. I notice most of time it’s P7 DV (FEL/MEL) that is stuttering, though Gladiator (Framestor Extended) seems to work but I don’t get the DTS-X notification I usually get.

  2. DV P8.1/HDR10 seems to work fine.

  3. CE 21.2 works great on all, no stuttering and got DTS-X notification on Gladiator, though no DV.

Forgot to mention that. With the current approach of making this work it needs the gui to be native resolution, seems some (all?) boxes can’t do a 4k gui at > 30Hz while playing a video.

OSMC have shown that you don’t need a licenced chip to use the hardware that embeds the metadata. Working out exactly what they did to copy it would probably solve that issue.

Aside from that I haven’t seen any issues on remuxes, maybe the 4k gui again causing an issue with overheating?


Haven’t touched the audio (aside from removing the hardcoded 4 frame delay).

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I’m running the GUI at 1080p 120Hz, should I try with another resolution?

btw, I also run a fan on the two Homatics boxes and this Vontar X4 too, so temperatures are very low. :slight_smile: it’s not like the Ugoos AM6B+ which has good cooling already.

Shouldn’t matter - when starting a video it should change to the matching resolution/frame-rate. But who knows…could try anyway.

If temps aren’t a problem, not really sure what is happening with the FEL/MEL having issues compared to the p8.1. They aren’t even distinguished in the code as are all treated identically - only difference there is bitrate.

Suppose just check generic CE stuff - that all the other settings are the same both installs. Audio passthrough for DTS is enabled, cache settings are the same etc?

edit: could also try playing with the whitelist as by default CE doesn’t use all available options and this work really does need the native resolution/framerate of the video to be used.

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Newer to using custom builds like this one. After I install the August build do I need to install all of the updates individually or can I just install the latest update and be good to go?

Thank you for your time.