[QLab] Live video input

[Christopher Ashworth]

On Mar 12, 2007, at 10:56 AM, Daniel Hoole wrote:

> Sorry Chris, Here is the actual question (cat ran over the keyboard).
> I know that the answer is probably going to be no, but here goes....
> I've just had a production meeting for a show which will involve 16
> video playback sources. All sources need the same picture (easy enough
> with VGA splitters), but the designer would like a live camera feed
> fed to the monitors as well. Is there a way of feeding live video
> through Qlab, or using Qlab to fade in live video (using something
> similar to AU Lab), without the need of vision mixing?

Maybe.

Here's the deal:  Quartz Composer offers a "video from external  
camera" generator.  It's extremely easy to make a Quartz Composition  
that does nothing more than feed an external video input to your  
display.

The really cool thing is that Quicktime will play Quartz  
Compositions.  (It doesn't offer the full range of interactivity, but  
most rendering features Just Work.)

The obstacle is this: When I play back a Quartz Composition with  
video input in Quicktime Player, it works as advertised.  When I try  
it with the current version of the Video Cue, I get an error that:

Sequence grabber initialization failed (error -9405)

Let me see if I can fix this.  If so, you'll be able to use your  
current Video Cues for live input as well.  If not, you may still be  
able to use an external playback environment a la AULab to do the  
same thing.

-C