Project instructions 
Background change for real-time video is?required. 

Usage scenarios: 
When you have a video call with your teacher,if you are at outside but you want to show you are at office and work hard,you need to change your video backgroud real-timely.Samely, if a worker want to show he is at office but not the court when talking to his boss,he need real-time?background change.This project is for that.You need to write codes to change the background real-timely, as vivid as you could. 

Advice 
First step:Background modeling, distinguishing background and objects.
Second step:?Image fusion, so that more realistic.?
Advance step:Grab real-time video on the web, replace the background and display

References
1£¬Barnich O, Van Droogenbroeck M. ViBe: A Universal Background Subtraction Algorithm for Video Sequences[J]. IEEE Transactions on Image Processing A Publication of the IEEE Signal Processing Society, 2011, 20(6):1709-24.
2£¬St-Charles P L, Bilodeau G A, Bergevin R. Universal Background Subtraction Using Word Consensus Models[J]. 2016, 25(10):4768-4781.
3£¬Farbman Z, Hoffer G, Lipman Y, et al. Coordinates for instant image cloning[J]. Acm Transactions on Graphics, 2009, 28(3):341-352.