Hallo Moritz!
I'm on a project where i need live video input. i work with linux/pd/~/hid/pdp. and with my cheap webcam (creative instant) i have no problems, but for this project i would prefer have a better Video-quality, i have a Sony Dvcam here, where i think it will give me better results, but i have no succes yet. the dvcam has a usb- firewire- av- port, but anything i triied dont work right now.
you could also get the camera input in gem and then use pix_2pdp to use the video in pdp ... (I also used this in performances in it worked quite okay ...)
But DV input will always use much cpu ...
LG Georg