System and method for realizing information interaction between computer and pen and paper based on camera

The invention discloses a system and a method for realizing information interaction between a computer and a pen and paper based on a camera. The information interaction system comprises square paper, the camera, a controller, a parameter setting unit, a memory and a display, wherein the square paper is tiled on an operating platform; one or more groups of graphics and text information are drawn on the square paper by the pen; the controller is connected with the camera; and the parameter setting unit, the memory and the display are connected with the controller respectively. The information interaction processing method comprises the following steps of: 1, preparation before the information interaction; and 2, the information interaction, namely, acquiring background information, extracting foreground information, detecting the edges of the square paper, identifying information class symbols, classifying the information and performing information processing according to information types respectively. The invention has a novel and rational design, less investment and good using effect, is convenient to control and write, is highly operable, and can simply and conveniently combine modern computer technology and paper-pen input to which a user is accustomed.