i might be in charge in the near future of setting up the internals of some conference rooms, and they would like to record everything that's said in this room at times of meetings. i would like to mount some kind of microphone on the roof of the rooms, and have it stream audio data to a central server, where it will be stored and can be accessed on the internal network by authorized people. now, if i play my cards right, i'll be able to scale this system by however many rooms by just adding yet another microphone. therefore the need for an internal codec. if my wifi network gets saturated with 30 mics running at the same time, then there will be trouble a brewing concerning bandwidth. also, for security concerns, WEP and IPSEC would be helpful to deter anyone with a laptop's curiosity (which there will be many likely present), adding to the overhead.

as for the server internals, i'm thinking an apache/php/mysql solution to store and serve the data, and allow interface to the internal network's user database. i'll think of this later, once i source the mics. the problem is, i'm having trouble finding any mics in production that fit this criteria. if there's no off the shelf solution, any electronic engineers in the room wanna tackle this project?

[edit]wired solutions are not an option, because of apperance concerns and the reluctancy of drilling into the roof.[/edit]

Not sure about off the shelf solutions but a SBC with audio inputs and a PCMCIA slot for the WiFi card should be able to do it. Not gonna be cheap tho.

like this? this is actually good, if i knew enough embedded linux implementation. hmm... who in the world do we know that can do that? =)

they would like to record everything that's said in this room at times of meetings.

I can't count how many times such a thing could have been useful to me.

Boss: I need you to implement feature X for product Y by date Z.

Me: Impossible. The basic design of Y doesn't support X. Serious ground-up redesign would be needed. Because you said in the initial design meetings for Y that we would never need X.

Boss: No I didn't.

Me: Click, click.

My recorded voice: Will Y need X? If so, we need more time to lay the groundwork for it now, before it becomes an issue.

Boss' recorded voice: No, we don't need X. We need to get this to customer Q by next month, so just do this quick and dirty and get it out to them.

Yep. Something like that. The problem that the SBC won't be cheap and you'll need one of them per room along with an WiFi adapter. That's not even including the omni directional mike you'll need.

Barix make something called the Instreamer which is basically a network connected MP3 encoder. If you bolt this to an WiFi AP or ethernet converter then you'll probably end up with a cheaper solution and no need for embedded software development.

Instreamer will require a minimum one ethernet brige per unit, along with the omnidirectional microphone. keep in mind, this is all going to be on the roof of the room. it might work, but thats a lot of hardware to hang. i'll keep on searching.

Post back if you find something ... I've wanted to mic a room for voice recognition for a long time but was never able to come up with a decent solution for it.

Does the output of the mic need to be digital? Why not use a cheap wireless mic (like a lapel-pin mic) and analog transmitter, and feed that into a computer elsewhere. It would seem that analog wireless transmission would be much cheaper/easier than the codec/WiFi route.

--Dan.

He's concerned with security I think so just using plain analogue is out.

Well, I suppose that will teach me to not read closely enough. Never mind!

--Dan.

I wonder if one of these could be hacked to do what you want? No IPSEC, but at least WEP.