Author Topic: HDMI /w HDCP bounce solution  (Read 1713 times)


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HDMI /w HDCP bounce solution
« on: July 24, 2008, 07:59:32 am »
I wanted to start a discussion on the feasibility of manufacturing a device capable of splitting and distributing HDMI signals.

As I understand it right now (and correct me if I am wrong), HDMI output from a STB must be directly connected to the output device to view the HI-DEF content. Cable and satellite providers will not provide unencrypted MPEG2 streams for premium channels from these devices, and probably never will. This unfortunately makes it infeasible to share this media in the traditional way that Linux MCE/MythTV shares standard definition content.

After watching the LinuxMCE demo with the HD STB (and the direct input feature) it occurred to me that this functionality could be expanded through a separate hardware device. This hardware device could take an arbitrary number of input HDMI signals, and distribute them to an arbitrary number of HDMI outputs. Splitting and or copying the content as directed by a RS-232 control connection to the Linux MCE core system.

This device is really an amalgamation of existing devices already on the market:
A) RS-232 Link or IR
B) HDMI splitters (decrypts 1 HDMI signal, copies signal to all outputs, re-encrypts signal)
C) HDMI distribution amplifiers
D) HDMI extender over 2x Cat6 lines

With a combination of these parts, it's possible to then bounce HDMI input signals to numerous output displays as long as there are two free Cat5/6 lines running to the display. The source and destination all controlled by the RS-232 control port.

After I began thinking about this some more it occurred to me that it might be possible to make a home brew device that is capable of such a feat, using existing HDMI splitters.

Say for example you had two HD-capable displays in your house, and two HDMI only output devices (STB, Blu Ray player). Therefor the system has 2-inputs (I1,I2), 2-outputs (O1,O2). The system would then have 4 possible states:
Code: [Select]
{ (O1=I1, O2=I2), (O1=I2, O2=I1), (O1=I1,O2=I1), (O1=I2,O2=I3) }.

The first two states can be achieved by simply "connecting" the HDMI inputs to the correct HDMI outputs in a passive fashion (no processing is required). The last two states are achieved by "connecting" the correct HDMI input to a pre-purchased HDMI splitter device, and "connecting" the two HDMI outputs to the respective output ports.

By utilizing an already existing HDMI splitter device, and HDMI extender devices this project could be completed without the need for a complicated design or expensive processors. Additionally the HDCP compatibility would be preserved assuming the HDMI splitter/extenders are HDCP compatible. Obviously the complexity of the project increases with the number of inputs and outputs.

Does this idea seem possible? Am I overlooking some major issue somewhere? Is there a better way to do this? Has this already been done?