1. A motion detection method, comprising: acquiring detection information of a background scene and detection information of a current scene, wherein the current scene is a scene comprising an object(s) to be detected and the same background scene; calculating the object(s) to be detected according to the detection information of the background scene and the detection information of the current scene, wherein the detection information is a disparity image or a depth image; acquiring extreme points of a horizontal projection and a vertical projection respectively of the object disparity/depth image; and pairing the extreme points of the horizontal projection and those of the vertical projection in one-to-one correspondence to determine the initial objects to be detected, wherein the object disparity/depth image is calculated according to the detection information of the background scene and the detection information of the current scene.