This library is aimed at doing computer vision by finding ‘blobs’ on an image , that is to say areas whose brightness is above or below a particular value. It allows to compute blobs’edges as well as blobs’bounding box. However, this library does not perform blob tracking, it only tries to find all blobs each frame it was fed with. It was primarly developped for Processing (Beta) but can be used in any java programs.
Download here.

Code for Processing (Alpha) is still available there though the interface and conventions changed a little bit when updating for Beta release. Nevertheless, st33d ported the code so it can be used with Beta version as internal applet classes. Useful if you want to tweak around and see how the algorithm works. Anyway, I recommend using the library which is more stable and robust.