First, I would like to thank those who have worked on tracker! It's an excellent program, and in these days of constrained budgets at universities Tracker has the potential to replace software that costs our labs thousands.

I am new to Tracker and I have been trying to use tracker to record the positions of little beasties (rats) as they explore their environment and interact with each other.  I simply place an innocuous circular decal on the animal's fur and record their position with a web cam.  The autotracking feature in Tracker works amazingly well (in some cases as good as Noldus's Ethovision), but I have experienced issues with large files.  As you might imagine, rats sometimes rear, groom themselves, chase their tail, dart about suddenly, or rollover, thereby either partially obscuring the colored decal or blurring it.  Thus, occasionally I have to insert a new key frame to get the autrotracking work again.

The problem is that as the number of frames searched increases (say, above 1400 or so), Tracker begins to slow way down both in terms of displaying the frames being searched and in terms of the user interface (it can take 10's of seconds to get the 'new key frame' cursor for instance).  Possible this is a natural consequence of adding new points to the track, but I wondered if might be a bug.  This occurs whether I use QT with 32-bit JAVA or Xuggle with 64-bit Java.  Also, it is not affected by the memory I assign to Tracker.

System information:
iMac, 27", Mid 2011
CPU: 3.4GHz i7
Memory: 16 GB
GPU: AMD Radeon HD 6970M 2048 MB
Mac OS X 10.8.2

Any help or advise would be appreciated.