(This method can provide relatively complete feature data of motion policy, with high accuracy and sensitivity, and has excellent functional performance. The modeling of the scenery is the technical key of the scenery subtraction method. Generally, the system adaptive learning time is set in the system setting period to model, and the learning time of 3-5 minutes is selected according to the "enthusiasm" of the setting practice. After the general system modeling is implemented, with the change of time, there will be some changes in the scenery.)