We learned in previous chapters that analyzing an image through some of its most distinctive points can lead to effective and efficient computer vision algorithms. This is also true for image sequences in which the motion of some interest points can be used to understand how the different elements of a captured scene move. In this recipe, you will learn how to perform a temporal analysis of a sequence by tracking feature points as they move from frame to frame.
To start the tracking process, the first thing to do is to detect the feature points in an initial frame. You then try to track these points in the next frame. Obviously, since we are dealing with a video sequence, there is a good chance that the object, on which the feature points are found, has moved (this motion can also be due to camera movement). Therefore, you must search around a point's previous location in order to find its new location in the next frame. This is what accomplishes...