In the previous two recipes, we learned how to track the motion of points and pixels in an image sequence. In many applications, however, the requirement is rather to track a specific moving object in a video. An object of interest is first identified and then it must be followed over a long sequence. This is challenging because as it evolves in the scene, the image of this object will undergo many changes in appearance due to viewpoint and illumination variations, non-rigid motion, occlusion, and so on.
This recipe presents some of the object-tracking algorithms implemented in the OpenCV library. These implementations are based on a common framework, which facilitates the substitution of one method by another. Contributors have also made available a number of new methods. Note that, we have already presented a solution to the object-tracking problem in the Counting pixels with integral images recipe in Chapter 4 , Counting the Pixels with Histograms; this one...