Motions.

[Gerrit Holl]

On 2006-10-11 00:26:38 +0200, Dr. Pastor wrote:
> I would like to track the motions of
> small birds in short (20-30sec) .avi films.
> What tool-set/programs would be wise to use?
> Thanks for any guidance.

I'd use PIL with numpy and subtract a birdless background picture
from each picture. Make that binary (choose a suitable treshhold,
100 or so) and you'll get a matrix for each frame with value 1 for the
position of the bird. Been there, done that, though my problem was
slightly easier: I had a few dozen of equal balls flying around and all
I needed was the average total position, not tracking each individually.
How to do that if birds pass each other (projecting 3D on 2D) I don't
know, but I'm sure it's been done before (not necessarily in Python
though).

Gerrit.