1. A magnetic scanning device for generating an image on a plane having magnetic powder, the device comprising: a magnetic read-write head; at least one processor; and a storage device coupled to the at least one processor and configured to store at least one image and a plurality of instructions for execution by the processor to cause the at least one processor to: acquire an image from the storage device; control, when the plane is placed on the magnetic scanning device, the magnetic read-write head to touch a reference point on the plane; generate an electric signal which reflects relevant information of the acquired image according to the acquired image; input the electric signal reflecting the relevant information of the acquired image to the magnetic read-write head; control, when the electric signal reflecting the relevant information of the acquired image flows through the magnetic read-write head, the magnetic read-write head to generate a magnetic field corresponding to the electric signal; control the magnetic read-write head to move and scan the plane from the reference point, to magnetize the magnetic powder on the plane by the magnetic field; drive the magnetic powder to move relatively to generate an image similar to the acquired image; check whether each pixel of the acquired image corresponds to a coordinate point on the plane; and change, if each pixel of the acquired image does not correspond to a coordinate point on the plane, the resolution of the acquired image and make each pixel of the acquired image correspond to a coordinate point on the plane.