Forums > Jitter

Create geometrical shapes controlled by changing pixels from video input

October 26, 2010 | 10:29 pm

Hello! I have an idea for a project but I’m not quite sure how to approach it since I’m new to Jitter.

Basically, I want to take a video input of black balls on a white surface and track their movement. Then I want to create geometrical shapes that correspond to those balls/changing pixels and animate them(for now just scale) live according to the balls’ position. I’ve used the jt.qt.grab, jt.matrix and unpack to evaluate video input and detect change but I’m not quite sure how to track each individual ball and create a corresponding animated shape. :/

Any direction and suggestions as far as what objects would be best suitable to achieve that would be much much appreciated.


October 27, 2010 | 10:38 am

As your video input seems to be quite "clean" I think a blob tracking with cv.jit library is a good start.

October 27, 2010 | 9:32 pm

Thanks Yoann.

I guess my main questions is how do I get the x and y values of a blob centroid? Which object do I need to unpack to get those values?

Also can I track one particular blob without loosing its boundaries when it get close to another blob?

I need this to be pretty much the same as what this tread is about , except I’m not using people’s faces but their bodies recorded from above so they look like black random shapes on white background.

will post my sketch soon…

thank you for your help

Viewing 3 posts - 1 through 3 (of 3 total)