Video Distribution Plan

[odpcmedia]

Hello everyone - please see the attached file for a schematic of the plan I've developed (with a bunch of help from this forum) to upgrade the video distribution setup in our church.

My concerns are the following - we have a few older projectors that are in other areas of the church (Hitachi CP-445) that do not have HDMI input. They are scheduled to be replace with a year or two, but I need to make them work as long as possible. I am worried about how to down convert, just wanted opinions on the BM SDI-Analog Mini Converter. Will that do the trick? It is not critical that these are full HD quality, standard SD is fine for what they are doing now.

Any ideas would be much appreciated. I have spent tons of time researching this, but as most of this stuff is fairly new tech, I would be grateful for any feedback from people who have experience with this situation.

Earl Tyndall
Media Engineer
Ocean Drive Presbyterian Church
North Myrtle Beach, SC

[Brad Weber]

I noted that a media computer and a video camera are the only sources. How do you see routing and switching between those? For example, would some destinations always have the camera as a source? Or always have the same source, e.g. the Welcome Center and Children's Theater always getting the same image? A full router gives a lot of flexibility but the Videohubs do not support salvos or presets, you apparently can set the software up to support routing a source to multiple destinations with a 'take' button but you have to manually select the individual sources and destinations.

Are you okay with simple cut/crash switching? I don't believe the Videohubs support any fades or transitions, only simple cuts.

How are you handling the associated audio, especially any live audio? Have you thought about the possibility of remote control for some of the displays?

[sempei13]

I think I'd run both cat5 (or cat 6) and rg6 everywhere. Depending on the adapters and/or converters, you can send a variety of signals over those cables and just upgrade the converters as time goes on.

I think hd-sdi is what I'd aim for and convert to hdmi at the TV's. HDMI is so limited in terms of distance (up to 10 meters/30ish feet without conversion) that it's virtually useless in anything larger than your living room. HD-SDI (and SD-SDI too) work over longer distances as do RF and Composite. Those four signal types can be run on RG6 with no problems, so that's why I always lean that way.

Paul

[Borggren]

The BM downconverter will work fine. You can also get component analog HD out from it.
You could consider inserting live sound on the 2 HDMI-SDI converters. They will embed the sound to the SDI signal, and then you will have both video and audio in sync all the way to all your destinations thru the videohub.
The videohub is a simple electronic patchfield, with cut between sources. It is not possible to change several crosspoints (source-destination) at the same time.
You could also consider a seamless switcher to switch between your sources. That will make nicer transitions, and depending of the model, also give you the possibility to key your lyrics etc in the lower third of your camera picture.

[Brad Weber]

Originally Posted by Borggren

The videohub is a simple electronic patchfield, with cut between sources. It is not possible to change several crosspoints (source-destination) at the same time.

I thought I read somewhere that if you enabled "take confirmation" in the software then you could select a source and multiple destinations before hitting "take", but I can't find that so maybe it turned out to not be supported. You can develop your own interface using their SDK or use a third-party control system to create presets or salvos.

I agree that if the camera and computer are going to be switched between live then you may want nicer transitions than a simple cut.

Originally Posted by Borggren

You could consider inserting live sound on the 2 HDMI-SDI converters. They will embed the sound to the SDI signal, and then you will have both video and audio in sync all the way to all your destinations thru the videohub.

I initially thought the same thing but after thinking about it more, I have to disagree. Unfortunately, the routers do not seem to allow breakaway, where you can route the audio and video separately, so if you use embedded audio it will always be the associated with the selected video source and I see some problems with that. One is that I see it being likely for someone to be speaking while a presentation is shown, to use the computer for lyrics or graphics while wanting live audio of musicians or the congregation and so on. You might get around that by running a separate mix output from the mixer to all SDI audio inputs so they all get the same audio. However, either initially or as the system grows you may find that you do not want the same audio mix for all destinations.

[DTV-Engineer]

Originally Posted by Borggren

The videohub is a simple electronic patchfield, with cut between sources. It is not possible to change several crosspoints (source-destination) at the same time.
You could also consider a seamless switcher to switch between your sources. That will make nicer transitions, and depending of the model, also give you the possibility to key your lyrics etc in the lower third of your camera picture.

To build on a point: the router does not synchronize the inputs, so when you switch between two free-running (that is, not genlocked or otherwise synchronzied) sources, your output is going to cause the monitors or projectors to either roll or blank until they get locked back up on the new source. The ATEM Television Studio (for example) incorporates the necessary processing to prevent this problem.

There's a very easy way to group-switch a bunch of outputs without using salvos: simply connect a short jumper from one of the router's outputs (call it output X) back to one of the router's inputs (input Y). Then, instead of switching your feeds to different monitors according to the actual sources you want, just feed them input Y. Then, simply changing what's feeding output X automatically switches all of those monitors (or whatever) in tandem. The delay through the router is minimal -- on the order of nanoseconds -- so latency is a non-issue; since it's SDI video, quality loss is also a non-issue.

-- Jeff

[TJ Krusinski]

Do it right and buy a Television studio now in addition to the router, then you can have much more control. Put all the inputs and outputs from the switcher in the router and all the sources and destinations as well. Full Control and peace of mind. Which, what's better than peace of mind?