A first interpolation processor of an image processing apparatus performs a first interpolation process, using values of a plurality of input pixels of an input image aligned in an arranged direction that is one of a horizontal direction and a vertical direction. Thus, the first interpolation processor derives a value of each of a plurality of noted points on an inclined interpolation line inclined relative to the horizontal direction and extending through a location of a processed pixel of an output image. Moreover, second interpolation processor derives a value of the processed pixel by performing a second interpolation process, using the derived values of the plurality of noted points on the inclined interpolation line.