1. An image processing apparatus comprising: input means for inputting contour line data of image information; means for making a contour line pattern of said image information on the basis of said contour line data; means for making a painted pattern in which the inside of the contour line pattern was painted; means for narrowing said painted pattern, thereby making a narrow painted pattern; means for obtaining an AND of said contour line pattern and said narrow painted pattern, thereby obtaining a pattern for correction; and contour line correcting means for obtaining an exclusive-OR of said painted pattern and said pattern for correction.