I am currently working on integrating an object tracking algorithm of my own making into the Mission Planner. The algorithm combines Lucas-Kanade and SURF and attempts to learn negative and positive reinforcement values as it runs. Right now it is in the early stages of development, but I hope to have something fully functional within a few months.
My hope is to use this to aid in automatic centering of the tracked object by sending commands to the APM to move the camera gimbal based on the distance of the tracked object from the center of the frame. In the videos below you will see two demonstrations of this tracking algorithm. In both cases it seems to perform well with background noise.
NOTE: I apologize for the terrible frame rate of the videos. I don't have very good screen capture software. The second video is a little higher quality.