3 ms·

I could be wrong, but I was under the impression that you can get cheap Chinese HDMI splitters that strip the encryption. I would think it has to be relatively

I could be wrong, but I was under the impression that you can get cheap Chinese HDMI splitters that strip the encryption. I would think it has to be relatively easy to decrypt given that the Blu-Ray player has to either send a decryption key to the TV via the HDMI cable, or the TV has to already have a decryption key that could presumably be skimmed.

tehwebguy 4y ago
From what I can tell the splitters essentially convince the playback device to play by relaying whatever HDCP messages the TV sends: Playback Device (Roku etc) | | Splitter ------ Unauthorized Player (Recorder) | | Authorized Player (TV) Without this the Playback Device will show a black screen, an HDCP error message or something similar, but even with the splitter & an authorized player it seems the content can be encrypted. Since the TV obviously has the capability of decrypting the content it seems like there should be a way to split the signal somewhere between the main TV board and the display panel(s), which sounds like a big deal. Or maybe someone could make an incomplete splitter / recorder that just needs a legit Samsung board attached to it?
- everforward 4y ago
  I did a Google because I was curious, and some of them do indeed strip the HDCP. I think what you're saying is basically what's happening. The HDMI splitter pretends to be a display/TV, so the playback device sends encrypted data to the splitter, which decrypts it and forwards the decrypted part over the HDMI connections. From what I could find, it's usually the cheap HDMI splitters that emit unencrypted data over the HDMI ports. That kind of makes sense; they implement HDCP inbound because they have to, but they leave HDCP off the output ports because it reduces their manufacturing cost. I think you can't just "forward" the encrypted packets, because then both outputs on the splitter would try to communicate back to the player, causing issues. The splitter has to MITM the connection. https://www.tweaking4all.com/home-theatre/remove-hdcp-hdmi-signal/ https://www.tweaking4all.com/home-theatre/remove-hdcp-hdmi-s... has some cursory info, and links to HDMI splitters that strip HDCP (not an endorsement of whatever you do with them, just an interesting device).
goosedragons 4y ago
They exist. My cheapo $20 USB HDMI capture card does it too and I can use OBS to record Blu-rays off my PS3 for example.
- johnchristopher 4y ago
  Is that what they used to "record" amazon, disney, etc. movies and tv shows ? I was still picturing social/computer hacking.

tehwebguy 4y ago

From what I can tell the splitters essentially convince the playback device to play by relaying whatever HDCP messages the TV sends: Playback Device (Roku etc) | | Splitter ------ Unauthorized Player (Recorder) | | Authorized Player (TV) Without this the Playback Device will show a black screen, an HDCP error message or something similar, but even with the splitter & an authorized player it seems the content can be encrypted. Since the TV obviously has the capability of decrypting the content it seems like there should be a way to split the signal somewhere between the main TV board and the display panel(s), which sounds like a big deal. Or maybe someone could make an incomplete splitter / recorder that just needs a legit Samsung board attached to it?

everforward 4y ago
I did a Google because I was curious, and some of them do indeed strip the HDCP. I think what you're saying is basically what's happening. The HDMI splitter pretends to be a display/TV, so the playback device sends encrypted data to the splitter, which decrypts it and forwards the decrypted part over the HDMI connections. From what I could find, it's usually the cheap HDMI splitters that emit unencrypted data over the HDMI ports. That kind of makes sense; they implement HDCP inbound because they have to, but they leave HDCP off the output ports because it reduces their manufacturing cost. I think you can't just "forward" the encrypted packets, because then both outputs on the splitter would try to communicate back to the player, causing issues. The splitter has to MITM the connection. https://www.tweaking4all.com/home-theatre/remove-hdcp-hdmi-signal/ https://www.tweaking4all.com/home-theatre/remove-hdcp-hdmi-s... has some cursory info, and links to HDMI splitters that strip HDCP (not an endorsement of whatever you do with them, just an interesting device).

goosedragons 4y ago

They exist. My cheapo $20 USB HDMI capture card does it too and I can use OBS to record Blu-rays off my PS3 for example.

johnchristopher 4y ago
Is that what they used to "record" amazon, disney, etc. movies and tv shows ? I was still picturing social/computer hacking.