1. A method for object detection and tracking, for detecting and tracking a plurality of continuous videos generated by the object motion in a scene, said method comprising: based on an input new video and the past accumulated information, updating information of a foreground appearance model and a background appearance model; based on information of said updated background appearance model and foreground appearance model, past propagated time axis information and current observed video, performing an object detection process; using detection result from said object detection process to update said information of said foreground appearance model and background appearance model until a convergent condition being met; using said convergent detection result as a new tracking measurement to update a tracking prediction model; using said updated tracking prediction model to obtain a final tracking result, said final tracking result being determined according to current tracking measurement and past observed tracking result; and predicting location of tracked object at the next time, and returning predicted labeling and appearance information of foreground and background objects as information required in the step of updating said foreground appearance model and background appearance model.