Urgent video chat application? sounds like trouble.... :)
I recently had to look into this for a project and found it to be very difficult and a bit unreliable. The best success I found was this:
1. Have processing launch an applescript (bat file on windows, other problems with this though, see below)
2. Applescript launches VLC and starts a camera capture that streams over the network (could be other ways to send the video)
3. Have another computer launch a processing app that is set to look at the IP address of the computer sending the video signal. I used GSPipeline to capture the video over an IP. GSPipeline only works with Processing 1.5.1. IPCapture (
https://code.google.com/p/ipcapture/) however works with 2.0 and seems to be simpler to use (more like the built in Capture)
4. Show the video.
This worked pretty well on a mac, once I figured out the stream settings from VLC, but it was pretty ugly compression and lots of frames were dropped occasionally. I also had to figure out the GStreamer stuff on the Processing end, which was crazy complicated, and very few tutorials/info about. BUT... when I moved to the windows side, I found the GStreamer plugins that worked on Mac were not available. In the end we weren't able to get it working in the way we needed for our project and went a different route.
A library I started playing with recently that seems like it could have some potential in this application is IPCapture (
https://code.google.com/p/ipcapture/) which allows for capturing a IP stream from a webcam (or an android device in my case) I had great results getting the video to stream without having to mess around with GStreamer plugins on the processing end. The last piece of the puzzle for that solution is to get a stream to be sent from processing.
Hopefully this helps get you started, sorry I don't have a complete solution.
good luck!
ak