Imagine I have a video playing.. Can I have some sort of motion graphics being played 'over' that video.. Like say the moving graphics is on an upper layer than the video, which would be the lower layer..
I am comfortable in a C++ and Python, so a solution that uses these two will be highly appreciated.. 
Thank you in advance,
Rishi..
I'm not sure I understand the question correctly but a video file is a sequence of pictures that you can extract (for instance with the opencv library C++ interface) and then you can use it wherever you want. You can play the video on the sides of an opengl 3D cube (available in all opengl tutorials) and other 3D elements around it.
Of course you can also displays it in a conventional 2D interface and draw stuff on top of it, but for this you need a graphical ui.
Is it what you thought or am I completely lost?
Navigation graphics overlayed over video