Its the last thing I want to do - I've roughed out code for most of the UI elements, the plumbing for the back-end works (although you can hear it rattle in places and there is considerable scope for improvement) but the marker detection code just isn't up for to the job and is getting a rewrite to use camshift and a Kalman filter. I tried the Kalman on the current code and its effective in smoothing the jitter caused by variations in centroid position but the continual loss of marker and the extreme numbers I am having to use to sense when the markers are engaged/unengaged is making it a frustrating experience.
I MUST come up with something working by Monday so that I can do something with this and was hoping to be tweaking various parameters of the interaction today but I'm going right back to stage one. Very frustrating but I ran a few experiments with the camshift algorithm and feel its required to make the air-writing implementation flow smoothly.
All nighter it looks like then :(