What is SDR mapping HDR ? Is SDR BT2020 possible ?

Discussion in 'ZIDOO Z9S' started by afss, Jan 21, 2019.

  1. CJC

    CJC New Member

    I guess the big question is, will a firmware be issued to address this specific issue? If not I suppose I will return it. I’m not too keen in spending another $180 on a Linker. I have other solutions but they have compromises. I can play the files direct on my Oppo and get excellent picture and sound but no elegant interface. Or I can play them on my AppleTV with good video and a pretty interface but sacrifice Atmos/DTS:X.
     
  2. Markswift2003

    Markswift2003 Well-Known Member SUPER Administrator Beta test group Contributor

    Have to be honest I kind of doubt it as the application is niche to say the least, but it certainly wouldn't be detrimental to the operation of the device if SDR mapping HDR was changed to force HDR as well since it's not a mode you would choose if you had an SDR display.

    The other side of the coin is that the Vertex is the single most useful device I have ever bought for my home theatre - operationally and diagnostically - I can't stress enough how useful it is. So much so I'm thinking of buying another purely for diagnostics and leave another permanently in the rack.
     
  3. CJC

    CJC New Member

    I have heard people say they love it before. Why do you find it so invaluable?
     
  4. Markswift2003

    Markswift2003 Well-Known Member SUPER Administrator Beta test group Contributor

    My main operational use is to remove the HDR SEI message so my projector doesn't see the input as HDR - this means I can use custom gammas. It also has a very comprehensive RS232 protocol which I use to interface it with my control system (Crestron) for full 2-way control.

    Diagnostically it tells you what's happening when things aren't behaving as you expect - bit depth, colour space, HDR messages etc. Many of the issues I see posted on these forums can be solved with it by understanding just what's happening to the signal as it wends its merry way from source to sink.

    You can set EDIDs to whatever you want to either change behaviour of the source or test behaviour under certain conditions. You can matrix two sources with two sinks. You can scale, you can change bit depth and colour mode. I do find it utterly invaluable.
     
  5. CJC

    CJC New Member

    I bit the bullet and ordered one... So couple of questions. Where in my chain should I put the Vertex? It looks like the Vertex itself can do some HDR tone mapping is this true? If so, should I run all devices through the receiver put the Vertex between the HDMI out of receiver and my projector? Or if I need to use the Oppo to tone map, run sources to receiver, then Oppo, then Vertex then projector?
    Also, will the Vertex do any rec709 to BT2020 mapping? Thanks for the help.
     
  6. Markswift2003

    Markswift2003 Well-Known Member SUPER Administrator Beta test group Contributor

    Nice one! So the first place I'd try is between the Zidoo and the Oppo. I'd set the Vertex EDID to 11 which from memory is the full fat 600MHz one (I'm not in front of the GUI right now). This means that the Zidoo will be perfectly happy to send HDR BT.2020 through the Vertex into the Oppo and you can process that to SDR 2020 in the Oppo - this will get you up and running with the Zidoo working as you want with your PJ.

    Then start experimenting - there's loads of help here:

    https://www.avsforum.com/forum/37-video-processors/2902961-hdfury-vertex-owners-thread-137.html

    And @HDFury is always on hand for massively helpful advice.

    Also, update to the latest firmware:

    https://hdfury.com/tools/Vertex_1.36.1.43_GUI_1.34.zip

    This also includes the latest version of the GUI. It's going to be a bit of a learning curve, but well worth it.

    The Vertex doesn't do tone mapping - that's not what it's designed for but you're going to love the insight it gives you into what all your equipment is doing and how it handles the signal chain... so you can use it the way I do - for a specific purpose as far as the Zidoo and Oppo are concerned, but then more overall diagnostics as you learn what it can do and what it can tell you.
     
  7. Fatih Durmus

    Fatih Durmus Member

    Why zidoo can’t add hdr forced option or hdr to sdr on/off options?
     
  8. CJC

    CJC New Member

    I don't think it's a matter of "can't" but a guess they "won't."
     
  9. afss

    afss Active Member

    Now that we have relatively stable beta firmwares (i.e. 2.2.61), it would be great if Zidoo could start looking again at the HDR to SDR performance:

    - The build in HDR-> SDR modes have issues such as posterization that need to be improved.
    - An HDR to SDR-BT2020 mode would be a killer feature for most projector users - OPPO and Panasonic have developed this capability
    - HDR optimizer feature - this is something Panasonic has developed, which seems to be a dynamic improvement feature for low light devices (i.e. projectors). It does improve the clarity of highlights.
     
  10. Markswift2003

    Markswift2003 Well-Known Member SUPER Administrator Beta test group Contributor

    Completely agree, but unfortunately I don't think the SDK allows for such niceties. HDR to SDR can be improved and certainly should be (it's dreadful at the moment) but SDR.2020 is, I think, a pipe dream and mimicking Panny's HDR Optimizer, likewise. I'd love to be proved wrong though.

    A very interesting alternative will be the MadVR Envy, if and when it is released...

    https://www.avsforum.com/forum/37-video-processors/3053602-madvr-envy-anticipation-thread.html

    But it won't be cheap.
     
  11. afss

    afss Active Member

    Thanks Mark, this Madvr Envy sounds promising indeed !
     
  12. afss

    afss Active Member

    So I did some more HDR to SDR testing using the latest beta firmware (2.2.61) and the Vivid mode seems the best one by far, in terms of having the least posterization effect. I think as Mark points out, it will be difficult to expect a dynamic HDR optimization feature such as Panasonic does, but I believe it may not be a big stretch for Zidoo to actually implement a BT2020 color variant for the Vivid HDR->SDR mode as the gamma portion is reasonably good.

    So, Zidoo team, what we are asking is for you to keep the gamma portion of the HDR->SDR Vivid mode as it is, and add the option of SDR BT2020 as an alternative to SDR BT709, which is what we have today.
     
  13. Markswift2003

    Markswift2003 Well-Known Member SUPER Administrator Beta test group Contributor

    Worth an email to service@zidoo.tv - they're always very helpful & responsive
     
  14. afss

    afss Active Member

    Done :)
     
    Markswift2003 likes this.
  15. Schumy

    Schumy Member

    Hi, I have a HDR/SDR related question and appreciate any guidance and sharing - is there a setting in z9s which can let the user change thr chroma setting manually at any given time?

    I can't find any but such function would be extremely useful when z9s applies a wrong chroma on a movie file (eg sometimes a HDR movie would appears washed out/pale/no colour, or the other extreme example is overexposed).

    Thanks
     
  16. mirror

    mirror Well-Known Member SUPER Administrator Zidoo TECH Supporter

    Good news. will add HDR-> BT 2020 function.
    It will appear in the Auto HDR option, which will be mapping to BT2020 when the display device supports BT2020.
     
    afss, leonkoum, Markswift2003 and 2 others like this.
  17. Markswift2003

    Markswift2003 Well-Known Member SUPER Administrator Beta test group Contributor

    Now I am impressed!
     
  18. afss

    afss Active Member

    This is outstanding news. Zidoo will be uniquely positioned for projector user community!

    Very impressive customer service from Zidoo!!
     
  19. Schumy

    Schumy Member

    I m using an Xgimi 4K Lune which is supposed to support HDR, but I m not sure if that means it also supports BT2020. How does z9s currently handle/map HDR with such a projector before rolling out this new function? Thanks
     
  20. Markswift2003

    Markswift2003 Well-Known Member SUPER Administrator Beta test group Contributor

    If your pj supports HDR it will undoubtedly do it in the BT.2020 colour space (HDR ostensibly refers to the number of brightness (luminance) levels between black and white and BT.2020 is a colour gamut - basically the same thing but with colour - so more space - more shades of colour, between the primaries of red, green and blue).

    The Z9S currently has 3 HDR modes:

    1. Auto - does what it says!

    2. HDR to SDR - maps BT.2020 to Rec.709 colour and applies a choice of 3 gamma curves for luminance (unfortunately, currently not very well - leads to posterisation - but I have a suspicion it's the colour conversion at fault - don't know this for sure)

    3. SDR mapping HDR - HDR passes through and with SDR, Rec.709 is mapped into BT.2020 and luminance is mapped with what is effectively an inverse PQ curve.
     

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