1. An image processing method of an image processing apparatus, the method comprising: discerning pixels to be processed on the basis of a preset reference pixel value in a scanned image that comprises a plurality of pixels; drawing a pixel area including the pixels to be processed from the scanned image on the basis of a preset condition; and selecting whether to apply an image process to the pixels to be processed or the drawn pixel area on the basis of a percentage of the pixels to be processed in the drawn pixel area, wherein selecting the pixels to be processed when the percentage is larger than a predetermined value, and selecting the drawn pixel area when the percentage is smaller than a predetermined value.