A system development platform based on C++ BUILD is introduced in detail, and how to configure OpenCV in C++Builder environment is discussed. Finally, two application examples are given on this basis. After the analysis of new media's intervention in public art design, the interactive digital public art design and practice of new media public platform is explained in detail, from the practice of interactive digital public art design and Chinese painting in interactive digital public art design The methods and methods of public art design are analyzed from the two aspects of reference and application significance. Based on the classification framework of research methods that combines hierarchical logic, process logic and the characteristics of this field, this paper analyzes the methods used in doctoral and master thesis in the field of virtual learning community research in my country with research methods.