i'm looking to set up the ability to live-broadcast video from a local computer to the net. (local video, remote audio commentary from a shoutcaster, relayed off to a remote streaming server via quicktime broadcaster). the audio i think i've got sorted, simple matter of running a VOIP server and letting the shoutcaster connect to it, and routing its audio output to the mac encoding machine's input. we're planning to relay all of this off of a remote server with a 100mbit connection via the open source quicktime streaming server installed on linux.
the question is what to use on the mac for capture. (it's a 1.6ghz core2 mini).
there are simple analog to DV converters of course that will take S-Video and spit out uncompressed DV. that's fine, as long as the 1.6ghz mini can keep up with the encoding (will have to be mpeg4, since our source upload bandwidth for the video will be limited to ~500 kbps). i don't know if this is the case or not but i suspect the CPU should be able to keep up just fine, i could encode xvid ASP at HD resolutions and bitrates with a dual core opteron in windows in real time, so i would think the 1.6ghz core2 duo cpu could do 580x320 video @ ~400kbps in real time quite easily. but if not someone correct me if i'm wrong.
then there are also similar external boxes that appear to be able to hardware encode mpeg4, albeit some with limits (i found one that will only do 352x240 @ ~200kbps for instance, or this box
from plextor that will even do DivX, albeit with un-alterable presets, and no mention of whether it deinterlaces or not, and that's a must since the source video will be coming over S-Video). then there are even some that will do mpeg4 AVC in hardware for a bit more in price.
however the information on what can actually be used with quicktime broadcaster is sketchy. will hardware encoders work with it? or does it only want an uncompressed source so it can encode on its own?
i've done this stuff with linux before, which is not terribly difficult once you've got it set up since SDL lets you hook Mplayer into anything under the sun. it appears that quicktime broadcaster can do the same, i just wanna make sure of that before i run off buying capture devices only to find that they don't work