I want to make an app for test validation (on paper) with the camera (ex. android). Accordingly, I need to recognize filled response options on a paper, which I will do in advance.
Prompt, where to start? Where to dig? I know of the existence of the library OpenCV - it will help me?
Thank you.
OpenCV will definitely get you there.
Have a look at this tutorial: http://blog.ayoungprogrammer.com/2013/03/tutorial-creating-multiple-choice.html