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HDCP implication / restrictions

Discussion in 'Projectors, Screens & Video Processors' started by VirusKiller, Sep 20, 2005.

  1. VirusKiller

    VirusKiller
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    Sorry if this is newbie stuff, but what are the implications of HDCP?

    Am I right in thinking that an HDCP source (DVI-D or HDMI) can only be displayed on an HDCP-compliant (DVI-D or HDMI) display? i.e. an older projector with a non-HDCP compliant DVI-D input cannot be used?

    Also, can you feed a non-HDCP feed to an HDCP enabled display device? e.g. SDI feed via a scaler.

    Thanks,
    Joel
     
  2. Liam @ Prog AV

    Liam @ Prog AV
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    Correct and correct!

    HDCP source requires HDCP display

    But, HDCP display will show any source (e.g. SDI, via scaler, to DVI to projector).
     
  3. Welwynnick

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    According to the HDCP regulations that is exactly correct, even when the HDMI interface is daisy-chained via an audio or video processor. Of course, if you use a naughty box that decodes HDCP, those limitations go away.

    Yes, if the source does not apply HDCP encryption, then an HDCP capable display will still work.

    SDI is quite different, and HDCP does not apply. I believe that the SD Interface is taken from the output of the MPEG decoder which de-compresses the data, but before any video processing or HDCP encoding processes. Some say this potentially gives you the best picture quality. IF you can get a BD/HDDVD player with an HD-SDI output to feed a very good scaler, you would have great HD video without any HDCP to worry about. Not too sure about the IF....... though.

    On a slightly different subject, I just heard from a fairly reliable source that multi-channel high definition audio from a BD or HDDVD (yeuck) player will be constrained by the same HDCP interface protocols to the channel format of the terminating display device - stereo! That beggars belief. I sincerely hope that will not be the case, but that is what the HDMI spec says.
     
  4. Liam @ Prog AV

    Liam @ Prog AV
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    HD-SDI mods already available.... No costs confirmed yet, but as soon as the kit is here the cards will be too :thumbsup:
     
  5. VirusKiller

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    OK. That's clear.

    But what if you have an HDCP feed from a DVD player to a scaler. Presumably the scaler must have HDCP decoding? Will the output from the scaler be HDCP as well? i.e. Do scalers fall into the category of "naughty box"?
     
  6. Liam @ Prog AV

    Liam @ Prog AV
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    Scalers pass-thru the HDCP encoding i'm afraid.
     
  7. VirusKiller

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    OK. I can see that this might be a problem, but I can't quite see why!
     
  8. Liam @ Prog AV

    Liam @ Prog AV
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    It means even with a scaler you will still need a box of tricks (which are so widespread already that I doubt HDCP will even be a issue in the future)
     
  9. VirusKiller

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    OK. I think I might have it!

    Am I right in thinking that some DVD players output unprotected SD (480i and 576i) from their DVI-D or HDMI interfaces, but that any SD material scaled in to HD (720p and 1080i/p) in DVD players is HDCP protected. If this is the case then there is no issue with scaling SD sources because you don't want any internally scaled and protected HD output anyway (external scaler will do it better). In any case, you can do an SDI mod on a SD player.

    However, I recall reading that Hollywood wants un-tappable MPEG decoders in BluRay/HD-DVP players (i.e. no SDI mods). So, in theory, this would put a real dampener on getting hold of unscaled digital HD sources. In practice however, if you needed to scale HD material outside of the player or display, there are ways and means of doing it.
     
  10. Liam @ Prog AV

    Liam @ Prog AV
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    No your losing it now!!!

    Anything digital coming from a DVD or STB is HDCP protected. There are one or two exceptions to the rule, but in general if it's digital out from source it's protected. A scaler in this case is not a source, more an intermediary step so does not add or remove restrictions.

    But back on track yes there are ways of doing just about anything !!!
     
  11. VirusKiller

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    And I was blagging so well!

    OK, but SDI mods get you unprotected digital SD material.

    So... Assuming that I'm going to be staying with SD DVD for the foreseeable future (and given the upcoming HD format war and the reputed quality of scaled SD material, that's likely) then how about:

    SDI-modded Philips 963
    SDI-modded Sky+ box
    Scaler with two SDI inputs (Lumagen, iScan or Cinemateq)

    This would provide a very fine solution which should work with any display device I upgrade to in the future, unless manufacturers start making display devices that will only accept HDCP-encrypted inputs.
     
  12. Liam @ Prog AV

    Liam @ Prog AV
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    Yes sorry, I forgot to say except SDI. A 963 and Sky box, both modified, running through a Lumagen will give you an almost unbeatable picture!!
     
  13. VirusKiller

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    Hmm. You're quite a fan of the Lumagen aren't you! I must admit I've been leaning towards the feature set of the Cinemateq Plus II SDI, specifically due to the number and flexibility of inputs and outputs. I particularly like the parallel output feature (bypass one input to one output and process another input to a second output).

    And yes, I know you can get converter cables, but when you chop and change your system, it's so much simpler if you can plug in a SCART or an S-video cable without having to order a new cable.

    I realize that the Plus II doesn't have any HD inputs, but given my suggested system, that is not an issue.

    Oh, and it would look great sitting above my Meridian G68, not that we consider such things :D
     
  14. Liam @ Prog AV

    Liam @ Prog AV
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    You've actually just listed about all the reasons the Cinemateq is still on our books!! And it's a bloody impressive processor. All the input/output fun, number of inputs and looks are often high prioritised than out and out quality or having multiple timings for mulitple displays (Lumagen).
     

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