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Black screen using Blueray player or DVB-T receiver as HDMI input device

BSI-Dual65
Level 1
Level 1

We have a problem with our Cisco Telepresence Profile 65 Dual (C90, MultiSite, NaturalPresenter, Premium Resolution, Firmware TC5.1.4.295090):

Using a document camera connected via HDMI (as input source 'DVD'): works well.

Using a DVB-T receiver connected via the same HDMI input (as input source 'DVD'): black screen

Using a Sony Blueray player connected via the same HDMI input (as input source 'DVD'): shows the Sony startup animation when switching the Blueray player on, then: black screen

Seems to be a problem with the Codec. When connected directly to the HDMI input of the screen, the Blueray player works well.

Any suggestions for solving this problem?

Manuel

1 Accepted Solution

Accepted Solutions

Hi.

HDCP is a feature buildt into the chip handling handling the HDMI input.

I do not beleve the codec support that feature. It is about encryption beeing sent from the blu-ray, and codecs does not contain the decryption feature.

//Marius

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15 Replies 15

Marius Nedregaard
Cisco Employee
Cisco Employee

Hi Manuel.

This will not work.

I do not believe the codecs are supporting blu-ray to dvb-t copyright protection.

This is called HDCP,  http://en.wikipedia.org/wiki/High-bandwidth_Digital_Content_Protection

Telepresence is not designed for distributing copyrighted video.

//MArius

Hi Marius,

we did not try to transmit the Blueray or DVB-T signal during a video conference. We just tried to use the 65' screens of the system to watch TV and Bluerays. The strange thing is that the startup animation of the Blueray player is shown on the screen, but then the screen switches to black - even the players settings menu is invisible.

Manuel

Hi.

HDCP is a feature buildt into the chip handling handling the HDMI input.

I do not beleve the codec support that feature. It is about encryption beeing sent from the blu-ray, and codecs does not contain the decryption feature.

//Marius

Hi Manuel,

Basicaly it is HDCP in work

So Marius totally right.

Best Regards,

Artem Borodai

Hi Marius and Artem,

so, you are telling me that we bought a system with two 65' screens for approx. 80.000 Euro whose screens are not able to cope with HDCP - something any TV for 200 Euro can handle without problems? Come on ... ;-)

To be precise: The screens are able to handle HDCP. When connected directly to one of the screens the blueray player works fine. Our problem is that the player is one the other side of the room, and the HDMI wire for the document camera, the DVB-T receiver and the blueray player (we use the same cable and switch the signal as needed) is placed under the floor. So it would be very annoying to unplug the cable from the C90 input and replug it into the screen's input each time we want to see a TV programm instead of the document camera's signal.

Why can't the codect just send the HDMI signal 'as is' to the screen - which is definitively able to handle HDCP (as described above)?

Manuel

Hi Manuel.

You will be unable to use the DVB-T or blu-ray through the codec. That will simply not work, and it is hardware bound.

I do not know if the 65" screens support HDCP, but if they do all you need would be a third-party HDMI switch that are capable of switching hdcp - and you would have to connect it-between the codec and screen. Please note that this is not officially supported by cisco.

I am not even sure if the screens will work properly with that solution, so I would not recommend it.

If you want to watch blu-ray or TV through the screens, i would recommend you to manually swap the cable from the codec to the player unit.

//Marius

Hi Marius,

thank you for your answer. Okay, we will install a second cable going from the blueray player/ the DVB-T receiver directly to the second screen.

That leads us to the next question :

The second screen (the one without the camera) has three HDMI inputs. Input #1 is connected to the C90. When I connect the Blueray player to input #1 instead the screen shows the signal coming from the Blueray player (as expected): perfect!

BUT: in order to not having to switch cables all the time I would like to let the C90 connected to input #1 and to connect the blueray player to input #2 and the DVB-T receiver to input #3. How can I persuade the screen to show the signal coming from input #2 or #3?

Manuel

I would've thought changing screen input using the remote control for the screen(s) would be the simplest, and cheapest solution - or you could throw a  bit of money at it and use AMX or Crestron to switch the inputs using a small touch-panel.

We use AMX TP in combination with a HDMI matrix switcher in some of our auditoriums, but our requirements are probably a bit more extensive as we require a "presentation only mode" and a "telepresence mode" etc.

/jens

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Hi Jens!

> I would've thought changing screen input using the remote control for  the screen(s) would be the simplest, and cheapest

> solution

Yes, you're right. But unfortunately the system comes with only one remote - it controls the C90 codec. As far as I understand the codec has no control over the screens. But since each screen has three HDMI inputs I'm sure there is a possibility to switch between inputs. I just can't find anything on it in the system's documentation.

Manuel

I didn't refer to the remote for the codec - you should have a remote for each of the screens as well.

We use a large range of both commercial quality and "home" quality types of LCD monitors from 42" to 70" - and every single one came with it's own remote control.

You need to forget about the codec;

the codec only sees what is being sent to it from the external camera and/or presentation source(s) selected at the time, and sends this to the desired output(s) which is connected to monitors, projectors etc. - so yes, it could send one input to HDMI1 and a second presentation source to HDMI2 on the monitor, but that doesn't mean it will switch the input on that monitor from HDMI1 to 2 - that has to be done on the monitor itself - separately from the codec, either by using a separate monitor handheld remote control or AMX etc type of control.

Another option would be controlling both codec and displays using AMX etc with two modes: "Local presentation" and "Telepresence" modes.

/jens

Please rate replies and mark question(s) as "answered" if applicable.

> You need to forget about the codec;

> the codec only sees what is  being sent to it from the external camera and/or presentation source(s)  selected at the time,

> and sends this to the desired output(s) which is  connected to monitors, projectors etc. - so yes, it could send one input

> to HDMI1 and a second presentation source to HDMI2 on the monitor, but  that doesn't mean it will switch the input on

> that monitor from HDMI1 to  2 - that has to be done on the monitor itself - separately from the  codec, either by using a

> separate monitor handheld remote control or AMX  etc type of control.

Yes, you're right. But there is no separate monitor handheld remote. We purchased a Cisco TelePresence System 65-inch Dual. It came with a C90 codec, a camera, two 65 inch screens and one remote (for the codec). No seperate remotes for the screens. And I doubt a spare remote from the next electronics store would work.

Manuel

I think that what you should get is an HDMI splitter with a remote control.

//Marius

Manuel Bach wrote:


Yes, you're right. But there is no separate monitor handheld remote. We purchased a Cisco TelePresence System 65-inch Dual. It came with a C90 codec, a camera, two 65 inch screens and one remote (for the codec). No seperate remotes for the screens. And I doubt a spare remote from the next electronics store would work.

Manuel

Aha, that puts a different slant on things...

Would be interesting to know if the displays are manufactured by Cisco or if they just re-badge them, if the latter then a handheld remote could still work, unless Cisco does something silly like disabling IR etc on these. But as Marius says; a HDMI splitter with a remote will also work.

/jens

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"Why can't the codect just send the HDMI signal 'as is' to the screen - which is definitively able to handle HDCP (as described above)?"

C-series complies with HDCP, which means you will not be able to transmit this kind of content across a network, however, the codecs are perfectly capable of displaying this content locally - if Cisco allowed it to do so.

As has been explained by Cisco engineers to me and others; allowing this to happen in local mode will only create a lot of confusion, and no doubt countless calls to technical support from users asking why it works locally, but not when in a call - and that is something I can identify with working at a university.

So, until the HDMI standards have been changed and the ridiculous HDCP "feature" has been either modified or, hopefully, completely removed, this is what we're stuck with. (HDCP is, imo, pointless as it can so easily be removed, but that's Holywood etc for you)

It could also be argued that the codecs, in their current state, are fully HDCP compliant.

Besided, as Martin has pointed out, this has been discussed before - see the other threads.

/jens

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