virtual video source via effects?

[zakk]

Would it be possible to develop an effect that exported its input as an additional virtual video source?

I guess an explanation of why I'm asking this is probably the best illustration of what I mean:

I currently have a blackmagic intensity pro that I'm using to capture various sources, mostly video game consoles. I'm then using camtwist+quicktime broadcaster to stream some game play footage via justin.tv. However, I would also like to capture the raw 720p at the same time for use in other projects. Problem is the blackmagic is only useable by one application at a time.

I was thinking an effect you could insert anywhere in the chain that created a new virtual video source at that point would come in handy in this instance. I would just insert it first in the effects chain before I messed with the video source. Would this be feasible? What I'm unsure of is where in the video processing chain CamTwist resizes the video to the output resolution? I've been poking a bit at some of the Soft Vdig example code, but if this is going to be a dead end due to other reasons I'd like to know early.

Alternately is there a way to run two camtwist instances simultaneously?

I know there are a few camera 'rebroacasting' applications out there, but all the ones I've found are limited to 640x480 output and seem confused by the 720p+ inputs of the blackmagic card.

[SteveG]

I see what you're saying. Yes, it's possible to develop such a thing. Are you volunteering? Would recording be sufficient? That would be much easier to implement as an effect.

[zakk]

I've started on something that as grown in scope a bit beyond just a CamTwist plugin and more towards a generic video source 'rebroadcaster' (for lack of a better word) so we'll see how that works out or how long it takes...

However, I've noticed something strange and I'm wondering if this is something with my setup (although it happens on multiple machines) or CamTwist itself:

No matter what video size, video source (even flickr sets, desktop, etc) and no matter what software I use to capture it, the output of CamTwist seems to have a really variable framerate; it seems mostly independent of the framerate preference? Is this a known bug/limitation?

[SteveG]

The framerate setting is the max framerate. CamTwist will struggle to keep up depending on what you're asking it to do.