4 ms·

Lost me at the end, but good point in general, I think?

by webkike 12y ago

potatolicious 12y ago
I think he's referring to HDCP, which is a standard meant to prevent tapping into a HD video output for the purposes of recording. It's of pretty dubious effectiveness, and quite honestly has screwed me in the past more than a few times even when I was doing something 100% legitimate (like renting a movie on iTunes and trying to use my MacBook's HDMI out to the TV... and it refusing to play). Not to mention there are many, many more ways to record HD content from a source than tapping the video output.
- revelation 12y ago
  Well, it's certainly of no effectiveness whatsoever since the HDCP master key leaked and anyone can trivially decrypt a HDCP stream ever since. The NeTV (http://www.kosagi.com/w/index.php?title=NeTV_Main_Page http://www.kosagi.com/w/index.php?title=NeTV_Main_Page) does this in realtime. That doesn't mean they have stopped preventing people from watching their just bought content on a beamer or display without HDCP support. Oh no, that stuff continues right now. In the history of DRM, this is probably one of the most bizarre failures. You can reasonably assume it never stopped anyone from making illegit copies (capturing very high bandwidth interfaces like HDMI is decidedly non-trivial and simply not worth the time investment if there are much easier sources), while denying people who just seconds ago shelled out cash for your product access for a reason they will not understand and will certainly not appreciate.
  - jrockway 12y ago
    My complaint is that the standards committees are wasting their time on a replacement for HDCP: something nobody wants or needs. Meanwhile, where's my 120Hz 4k monitor.
  - beagle3 12y ago
    > The NeTV does this in realtime. No, the NeTV does NOT do any kind of decryption. What it does do is encrypt its own image using the same key in parallel, so that it can overlay its own display on top of the incoming display stream. It does include an implementatiom of HDCP that could be used for decryptioon if you work hard enough at it (and I would guess someone worked hard enough at it), but as it comes out of the box, NeTV cannot be used to strip off HDCP.
    - lelandbatey 12y ago
      Is there anything that does decrypt HDCP in real time? Something where you plug an encrypted cable into one end and it outputs an unencrypted source on the other? One that maintains things like audio?
      - 1offi 12y ago
        Sure: all SiI9187 based HDMI splitters do, e.g. amazon.com/dp/B005HXFARS
        jrockway 12y ago
        The amazon pages say they don't decrypt anymore. That's a fragile attack anyway, as I imagine the key they're using would be revoked. The only attack that works is one that uses the master key to generate keys that haven't been revoked, which I doubt their hardware does. (Illegal and all that. Just being an HDCP endpoint is easy; take the chips from your TV product and stick them in the splitter. "Oops, sorry." But then you get revoked.)
cnvogel 12y ago
> But hey, at least the standards committees are working on new > forms of DRM so the NSA can't tap your video cable and see your > screen. Or something. I think he was referring to the fact that industry fails to provide end-users with good, ubiquitous and easy to use cryptography for privacy, while on the other hand video standards have repeatedly been delayed through industry mandating ubiquitous cryptography for digital rights management. e.g. one of the (likely: many) topics that are being discussed in the committees designing the next generation of DVI/HDMI/DisplayPort standards likely is how to encrypt the video signalso that a customer is barred from recording a movie. Which delays the availability of future standards describing how to drive your 5K monitor at 60 Hz over then-improved HDMI/DisplayPort connections.

Lost me at the end, but good point in general, I think?

by webkike 12y ago

Lost me at the end, but good point in general, I think?

I think he's referring to HDCP, which is a standard meant to prevent tapping into a HD video output for the purposes of recording. It's of pretty dubious effectiveness, and quite honestly has screwed me in the past more than a few times even when I was doing something 100% legitimate (like renting a movie on iTunes and trying to use my MacBook's HDMI out to the TV... and it refusing to play). Not to mention there are many, many more ways to record HD content from a source than tapping the video output.

revelation 12y ago
Well, it's certainly of no effectiveness whatsoever since the HDCP master key leaked and anyone can trivially decrypt a HDCP stream ever since. The NeTV (http://www.kosagi.com/w/index.php?title=NeTV_Main_Page http://www.kosagi.com/w/index.php?title=NeTV_Main_Page) does this in realtime. That doesn't mean they have stopped preventing people from watching their just bought content on a beamer or display without HDCP support. Oh no, that stuff continues right now. In the history of DRM, this is probably one of the most bizarre failures. You can reasonably assume it never stopped anyone from making illegit copies (capturing very high bandwidth interfaces like HDMI is decidedly non-trivial and simply not worth the time investment if there are much easier sources), while denying people who just seconds ago shelled out cash for your product access for a reason they will not understand and will certainly not appreciate.
- jrockway 12y ago
  My complaint is that the standards committees are wasting their time on a replacement for HDCP: something nobody wants or needs. Meanwhile, where's my 120Hz 4k monitor.
- beagle3 12y ago
  > The NeTV does this in realtime. No, the NeTV does NOT do any kind of decryption. What it does do is encrypt its own image using the same key in parallel, so that it can overlay its own display on top of the incoming display stream. It does include an implementatiom of HDCP that could be used for decryptioon if you work hard enough at it (and I would guess someone worked hard enough at it), but as it comes out of the box, NeTV cannot be used to strip off HDCP.
  - lelandbatey 12y ago
    Is there anything that does decrypt HDCP in real time? Something where you plug an encrypted cable into one end and it outputs an unencrypted source on the other? One that maintains things like audio?
    - 1offi 12y ago
      Sure: all SiI9187 based HDMI splitters do, e.g. amazon.com/dp/B005HXFARS
      - jrockway 12y ago
        The amazon pages say they don't decrypt anymore. That's a fragile attack anyway, as I imagine the key they're using would be revoked. The only attack that works is one that uses the master key to generate keys that haven't been revoked, which I doubt their hardware does. (Illegal and all that. Just being an HDCP endpoint is easy; take the chips from your TV product and stick them in the splitter. "Oops, sorry." But then you get revoked.)

cnvogel 12y ago

> But hey, at least the standards committees are working on new > forms of DRM so the NSA can't tap your video cable and see your > screen. Or something. I think he was referring to the fact that industry fails to provide end-users with good, ubiquitous and easy to use cryptography for privacy, while on the other hand video standards have repeatedly been delayed through industry mandating ubiquitous cryptography for digital rights management. e.g. one of the (likely: many) topics that are being discussed in the committees designing the next generation of DVI/HDMI/DisplayPort standards likely is how to encrypt the video signalso that a customer is barred from recording a movie. Which delays the availability of future standards describing how to drive your 5K monitor at 60 Hz over then-improved HDMI/DisplayPort connections.