Question / Help Multiple Webcams / Captures on one PC... Possible?

[richard_hawkes]

Hi there all,

I have a rather ambitious project that (if I get the budget agreed) I may be able to get funding on. I am going to attempt to stream 4 Avermedia Live Gamer Portable streams, and (if possible) 4/5 webcams. So that's a total of 8/9 signals coming in that I then need to display in various scenes (eg all 4 in one screen, just one in another).

So... To quote an Americanism... Am I smoking crack?

I appreciate this is a big ask, and I'm wondering if a PC is capable of doing this sort of thing, even a ballsy one.

Has anybody had any experience in this area, and can reccomend a "relatively" cost effective way to produce such a stream?

Thanks in advance
Richard

 

[Kharay]

I don't know of anyone that has actually done this. At least, I haven't run across anyone that has taken it quite that far. But, I see no reason why it wouldn't be possible. In fact, I would say the one limiting factor in this is the hardware. Not the software.

 

[richard_hawkes]

Thank you Kharay... I agree, and I suppose my question is around the "right" way to do it. I mean, how do I get USB ports connected to my PC?!

 

[Kharay]

Extra ports? http://en.wikipedia.org/wiki/USB_hub

 

[FerretBomb]

I would strongly recommend against just tossing on a powered hub. Each USB host controller has a bandwidth limit per-controller; a USB2.0 hub attached to one port on a controller has a total of 280mbps (480 total, but overhead reduces actual throughput available greatly) which a hub cannot overcome. A single 1080p webcam will use ALL of the bandwidth on a single controller chain.

You need to space out your capture devices between the actual USB host controllers on the machine, so the bandwidth on a single controller isn't being choked. At MOST I'd put *one* camera and *one* capture device on each host controller. You can check devices by-connection in the Device Manager under the windows control panel.

Even then, if you're running multiple high-res cameras (Logitech c920 @ 1080p) you may STILL choke the host controller, depending on what the capture devices are putting out as far as a bitstream. Potentially meaning needing to use a separate controller for *each device* (one per camera, and one per capture device). Some controllers will use a separate channel (and full 280mbps for each port they have), but those are very rare and tend not to be used in almost any motherboards.
Also be aware that many motherboards have additional on-board headers for 'front mount', 'side mount', or 'auxiliary rear' USB ports which may have their own host controllers as well, but you may need to buy the breakout card-blocks to actually use them.

If you need more than are built into your motherboard, you'll need to buy PCIe USB host controller expansion cards and install them in the system. Some have two or more host controllers on each card.

It isn't just about having somewhere to physically plug things in. That's the easy part. Choke the bandwidth though, and your cams/capture devices will stutter, lag, and look like crap.

 

[dodgepong]

The Live Gamer Portable does not yet work with OBS, as I understand it, unless their latest update made it start working.