Image encoding method and image encoding apparatus

An image encoding method for an encoding system includes receiving a first image captured by a main camera and a second image captured by a sub camera provided in the same plane; comparing pixel values of pixels at first coordinates of each of the first and second images to obtain a first difference value; determining the first coordinates are in surface or back region in case of the first difference value is not more than or more than a first threshold value; pixel-shifting the second image by a first shift amount; and comparing the pixel value at the first coordinates of the first image with that of the second image after the pixel shift to obtain a second difference value, determining whether the first coordinates are in the surface or back region based on the second difference value, and recording into a second frame different from the first frame.