I'd like to write an application in c++ that will have to find the amplitude of movements of the one color point (actually the laser beam) on the one color screen (the movement is recorded on the movie). This mean I've got to find the position of the dot in every frame (that's how i think that should work).

Now the problem arises, because I don't know how to write it If you please can post links to documentation that is useful in this case.