There are provided an image processing method. Perspective is calculated from an image, the image is divided into a plurality of objects in consideration of the perspective, and processing levels of the plurality of objects are assigned. A light shielding rate of a transparent display apparatus is calculated based on the processing levels. Further, image processing is performed on the objects on the basis of the processing levels, so that it is possible to improve a stereoscopic effect being felt while using the transparent display apparatus. Furthermore, a shielding rate of light entering from the rear side of the transparent display apparatus is effectively adjusted, and the image is processed to improve the visibility of the image.