I also suspected that it produces fake DV. However, in a recent conversation with @KCX, I tried to find any proofs based on empirical data. But there is non to my knowledge. Only some guys stated that there is something wrong.
Fully agree with that.
It definitely seems the level of DV support is platform dependent. On Android, it seems simply updating the exoplayer version that supports DV profile 7 is only half the solution - the system (eg NVidia Shield) must also support the corresponding decoder for this profile, at least from my understanding of the docs: https://source.android.com/devices/tech/display/hdr.html#decoders
As a simple test to verify this, I grabbed the latest exoplayer source, compiled the demo .apk and tested it on the 2019 Shield with sample DV videos. The profile 5 file played in DV mode on the Shield while the profile 7 (which played in DV mode on my LG B7 TV) did not.
Iâd love to be wrong on this, but I donât think Plex/exoplayer alone can make this work, NVidia (or another 3rd party with the Dolby license that can create a decoder) would need to update their DV decoder to support files of type dvhe.dtb (profile 7) in addition to dvhe.stn (profile 5).
Now will NVidia support this in the future? My guess - doubtful because the only files that come in this format are UHD Blu-Ray rips, so Iâm not sure theyâd add support for a feature to play files that are not officially condoned. So why does the LG and some other TVs support this? Canât say for sure, but my guess is that when DV was strictly hardware dependent, all the profiles that the SoC supported came as a package.
Someone above mentioned why does Plex support profile 5 when there are no useful files that come in that format? There are, theyâre just the ones that are used by streaming apps - I donât think Plex did any work to support those, theyâre just a side effect of the hardware natively supporting them for Netflix, etc.
Just my observations - please correct me if I got any of this wrong.
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I suspect you are spot on.
It would probably take someone who is capable of reverse engineering/hacking of both the player/software, and hardware, to see if it could be pushed to (officially or unofficially) support the bluray profile.
Even though shield has become the âbest in classâ type plex device, simply due to it being able to pass truehd/atmos/dtshdma, I think unless nvidia determines that being able to sell a device with similar file based DV-7 support pays better and/or outweighs any other risks or costs.
Maybe we could convince them to support USB 4k/bluray-ROM devices, which would then require the direct support of DV-7.
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One more quick question, since DVDFab can create both types (âsingleâ and âdualâ layer, which I guess would be profiles 5 and 7)âŠis the suspicion that BOTH of these outputs by that software are âfake,â or just the âsingle layerâ ones?
I donât use dvdfab, but assumingâŠ
a) 4kbluray disk has 2 layers
b) dvdfab can rip both layers intact with no modification (ie passthrough)
then
c) dual layer should be native DV (of which there does not appear to be any software player to decode native dual layer DV ?)
d) something reading the main layer, would simply be standar HDR
for single layer, my simple guess is that dvd is simply changing (or inserting) the DV metadata info into the single layer HDR stream, that appears to âfoolâ the DV indicator to light up on various TVâs.
I donât really see dvdfab being a licenced dolby vision (re)encoder tool, so unless they have somehow reverse engineered the dolby decoder/encoder pipeline to decode DL DV into uncompressed video, then (re)encode that stream into a single layer DV stream, abusing the metadata is probably the simplest way.
It would not be surprising that DV is tied to specific hardware/chips, essentially a hardware dongle, to prevent mainstream DVision/Datmos encoding.
No doubt they want to avoid a situation where handbrake can take the place of millions of dollars worth of equipment/support/licensing profits.
I suspect that only single DV is fake.
Thank you for your efforts. That is exactly what I feared. As @TeknoJunky said, we should hope that Nvidia will support dual-layer DV⊠however, I donât believe they will.
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Ah⊠one question @crazydave80 and all others : did someone rooted/cracked/reverse-engineered the Shield, in the past? I wonder if this is possible and why nobody tried it. Mobiles are always rooted after a short period to make some software run. Maybe this could be the key. But if it is a matter of the hardware, we will never have a chance to get dual-layer DV.
However, as I mentioned somewhere else, there is already hardware out there that can play dual-layer DV: some TVs and this odd clone version of an Oppo player. This device does certainly not support Plex what is why I did not buy it in the past⊠maybe I will, because this topic seems to become a never ending story :-/
The Oppo is pretty dissapointing when it comes too like freedom,especially if you just want it for dual layer support,i bought a shield TV pro for a lot more freedom,and from my POV i atm use a super fast sandisk extreme pro that i connect too my tv when i need a DV support,the rest goes via shield
as for ja
Yes it has being done,mainly for people using emulators and stuff,i recommend looking at the site âmakemkvâ they are very busy their when it comes to Dolby Vision support, iâm gonna have a discussion with a few âpeopleâ that have experience with ripping, i have to see what they use,mainly because they use DVDFab but since that might be actually not proper anymore we have problemâŠ
To be honest, I always thought that DV while nice, is not (and may never be) worth the effort.
Really, HDR is plenty good enough.
If you REALLY want DV, stick in the disk.
I still hope that HDR10+ will make DV obsolete/irrelevant.
We need to depend less on dolby, not more.
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HDR10+ is neither supported by the Shield nor by Plex 
itâs not really out either.
but most importantly, its not dolby.
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NVidia actually provides rooted dev images/source packages for the Shield (although I donât see the site updated for the 2019 model, but maybe itâs there if you poke around on their server): https://developer.nvidia.com/shield-open-source so this would be the place to start looking, the hard part would be obtaining and plugging in a decoder that supports profile 7 into the OS image.
Even if NV started supporting UHD drives (unlikely since discs are a niche format compared to streaming), thereâs no guarantee they will support profile 7. Windows 10 has official UHD disc support but PowerDVD (the only authorized player) only supports HDR10, not DV. Windows even has a Windows Store app to enable DV (but only available on select models of PCs, enforced by an ICM profile that checks the OEM string on the BIOS), and even that only supports profile 5/8. Same story with Apple, the latest devices support DV but not profile 7.
HDR10+ is a more open standard, but thereâs a severe lack of content and TV support, not to mention that DV is seen as a higher quality picture.
So yeah, not an ideal situation for those of us who care about the best possible format and also the convenience of setting up our own media server⊠but hey, you never know what will turn up in the future.
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So is there anything new on this now that MKV supports Dolby vision? It seems like I can play both kinds of rips in plex but as far as I can tell some of them take a couple of tries to get Dolby Vision to trigger and I assume these are the profile 7 ones.
@TobyX Thank you for posting this.
I too agree that dual-layer DV support is the best path forward due to the hardware limitations of single-layer DV.
Take my home as an example. I currently have 3 TVs and a multitude of video-capable devices in my home. Out of all of the devices, only one(1) supports DV. If I were to rip all of my DV content into single-layer files, the possibility of running into a device that canât play back that file is higher.
In my opinion, that is not a very good user experience. One thing Iâve always wanted to see Plex do is be more versatile in its stream sourcing (a topic for a different discussion). In an effort to meet that goal, implementing support for the most versatile technologies and methods is key.
From a high-level technical perspective, I donât see how a dual-layer MP4 and a âdual-layerâ MKV are different (two video tracks in the same container). I spent countless hours testing the various methods and I am pretty well versed in how to execute each implementation. I would be more than happy to offer any technical assistance and/or information to the Plex team, if needed.
Dual layer would be really fun to have,but i think this is also a software limitation that is not at fault by plex,but at fault with Dolby,they do not seem to be releasing it,ive used dolby vision dual layer on plex via my TV,but via my nvidia shield tv pro it does not work. this has being a while back and iâm not sure if nvidia/dolby/plex released a update for taht
@tazlord You are confusing âsingle-layerâ and âdual-layerâ with âsingle-trackâ and âdual-track.â
âSingle layerâ Dolby Vision doesnât contain the EL (enhancement layer), but rather the BL (base layer) + RPU.
âDual layerâ Dolby Vision contains BL + EL + RPU, which can be implemented in a single track (which is what the current version of MakeMKV generates), or in the MP4 container with the EL+RPU as a second video track.
Many people think âdual layerâ is the same thing as âdual track.â It isnât.
@Jim29er Thanks for the clarification. My mistake for using bad terminology.
However, I am well aware of how DV can be implemented and the case of every DV disc Iâve ever encountered, itâs always been Track 1: Base Layer + Track 2: Extended Layer + RPU. I have yet to encounter a commercially released DV UHD title that does it differently.
@tazlord Yes, understoodâŠI believe that track separation is necessary on the BD media to maintain the âbackwards compatibilityâ with HDR10-only playback devices, as those wouldnât be able to âparseâ the single track. I donât know that the separation âdirectlyâ translates to a need for having that separation in an extracted container format.
Does this make sense? If there is documentation somewhere that supports that notion one way or the other, please educate me so that I can correct my understanding.
@Jim29er That makes sense.
I am not sure if any documentation exists at all when it comes to trying to standardize how to implement DV in distributable container formats. As it stands today, players that can support any level that they see fit. A product like Plex can possibly have an influence on how other vendors choose to implement.
That being said, I personally would always choose the most versatile path available. Especially since creating single-layer DV files is not only limited in the software available to achieve it but also the fact that many people like to save space when creating a library so being able to create your own DV files with re-encoded assets is a pretty important piece of the puzzle.
Either way, some sort of standardization needs to happen and with as little disruption as possible (i.e. having to purchase expensive proprietary software to create your own DV library).
@tazlord I wholeheartedly agree!
Iâm still happy this is even possibleâŠI was skeptical that the day would even come.
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