1. An image processing method, comprising: receiving an image, the image including a readable symbol and a readable object disposed around the readable symbol; reading the readable symbol in the image; extracting a quiet zone that is in contact with a readable symbol area in which the readable symbol is formed in the image, the quiet zone not including the readable object; setting a mask area containing the readable symbol wherein the mask area extends within the quiet zone; and recognizing the readable object located in an area other than the mask area of the image.