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  1. Completing my video library took me a massive amount of time and I opted for REMUXes since it seemed the best quality and I dont care for all the clutter but the main movie anyway.

    Just to make sure I understood some of the HDR developments I have some questions and maybe some of you clever folks can answer those.

    a) If Mediainfo says HDR10+ it means that REMUX actually is HDR10+ and it means, all HDR10+ meta data has been retained and if the corresponding hardware requirements are met, this REMUX mkv would play as a HDR10+ video and if not, fall back to a plain HDR10 video, right? (cant test, need to upgrade equipment first).

    b) I know the MKV container could easily contain the Dolby Vision tracks but there’s no hard- and software out there to put the HD video track with the 2bit plus Dolby Vision meta data and the UHD 10bit video track together to form the 12bit Dolby Vision video but my question is, why shouldn't I do it anyways? Would it not make sense to still produce an MKV REMUX with those 2 video streams hoping that some day Dolby opens up and the corresponding hard/software can be made? As far as I understand, this file would still play on current hard/software but just as a HDR10 video or am I wrong?

    I figured, I should be fine with HDR10+ MKV REMUXES but for the DV releases I would need to keep the full UHD BluRay as an ISO or folder structure to make sure DV stays intact?
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  2. Member Cornucopia's Avatar
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    A. I would test first.

    B. I don't think it would work. Here's why: the metadata isn't global, it is pixel mapped. Iow, pixel 1 may have a transfer function that puts it in the superbright range, while pixel 2 right next to it may be meant to be very dark.
    So the contrast between neighboring pixels could be quite high (though for natural images, not usually that sharp a slope). If you were to merge these 2 streams' info, assuming you could and I'm still skeptical about that possibility as it is breaking the 1:1 correspondence, you would be applying HD metadata to UHD pixels, thus every quad cube of uhd pixels would have the same transfer function. Possibly creating illegal values, but more likely rendering the contrast to be restricted to the HD level, thus negating much of the benefit of the UHD version.

    Scott
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  3. @Scott, thanks for that.

    a) cant but it's ok, unlimited storage means I just keep another copy until I can test

    b) sorry, I wasn't very clear there. I'm not merging anything myself. as far as I understood, what I described is how Dolby Vision works. the meta data and the 2bits addition are already saved in a "bogus" HD 1080p 2nd stream inside the original UHD Dolby Vision BluRay and then there's the 1st stream, the "normal" UHD 10bit HDR movie stream. if I understood correctly, this is done to keep compatibility.
    as fast as I can see looking at other people's work, putting the 2 streams inside a MKV container is already being done since a long time. it's just that no one has figured out how these 2 streams would relate to each other when playing (cause Dolby does not supply that information).

    re: b) all I'm really unsure about is, was this done by others on purpose - possibly with the same idea in mind that I mentioned above - or by "accident".
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  4. Member Cornucopia's Avatar
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    Oh, OK. Gotcha.

    BTW, don't hold your breath expecting Dolby to EVER release any of their IP code. It's been 40 years since Dolby Surround came out (late 70s for theatres, Star Wars was a big initial one) and they still haven't even given that info out. Even though that matrix is fairly straightforward (as is Pro Logic), given their literature, it's always been either guessed-at reverse engineered, or licensed.

    I can make an educated guess about the base+enhancement layer methods (similar to many other parallel technologies), but without going beyond generalities, it's pointless, as we don't/won't know the syntax. I do think it (Dolby?) might be cheating if they use a lesser rez enhancement layer. That isn't unknown, however: PhotoCD did it decades ago, based on differencing of progressively higher or lower rez versions from the base.

    Scott
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    Originally Posted by hypersucker View Post
    @Scott, thanks for that.

    a) cant but it's ok, unlimited storage means I just keep another copy until I can test

    b) sorry, I wasn't very clear there. I'm not merging anything myself. as far as I understood, what I described is how Dolby Vision works. the meta data and the 2bits addition are already saved in a "bogus" HD 1080p 2nd stream inside the original UHD Dolby Vision BluRay and then there's the 1st stream, the "normal" UHD 10bit HDR movie stream. if I understood correctly, this is done to keep compatibility.
    as fast as I can see looking at other people's work, putting the 2 streams inside a MKV container is already being done since a long time. it's just that no one has figured out how these 2 streams would relate to each other when playing (cause Dolby does not supply that information).

    re: b) all I'm really unsure about is, was this done by others on purpose - possibly with the same idea in mind that I mentioned above - or by "accident".
    see this article - https://www.dvdfab.cn/resource/4k-media/hdr10
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  6. @Scott Thanks mate

    @October, read through it and it doesn't relate to my very specific questions
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