i think his software is still buggy.
my method (see included black and white image, blob_find2.png) gets rid of 99% of the noise and is very robust, meaning i dont need to tweak it for it to work. but for some odd reason, the center of mass module only tracks the blob when it covers 80%+ of the space. otherwise it just hangs in some random location . . .
so i redid it using the roborealm method (see black and red image). the center of mass then works, but that method doesnt get rid of all the noise, making the center of mass mostly wrong.
ill email the guy . . .
oh, and the image is me moving a red object around in my kitchen . . .
so i read the documentation some more, and found this:
"Note that based on the way this COG is calculated brighter pixels will exert more pull on the final COG location than darker pixels."
so applying the negative to the image, the center of mass works better, but still is way off too much. (see blob_find3.png)