Upscaling circuits include a difference circuit which calculates a gradation value of a target pixel with use of differentiation or difference of gradation values in vicinity to the target pixel, so that an edge of an article pictured in an image can be extracted; an averaging circuit which calculates a gradation value of a target pixel by averaging gradation values in vicinity to the target pixel; and a correlation operation circuit which calculates a correlation value indicating a correlation between difference image data and averaged image data, the difference image data being produced by carrying out the difference operation process on the divided image data, and the averaged image data being produced by carrying out the difference operation process and the averaging process on the divided image data. Further, an interpolation process is carried out on the divided image data with an interpolation method using the calculated correlation value.