In a case where density adjustment is performed on a plurality of density ranges, adjustment setting values of adjacent density ranges affect one another, and therefore, tone reversal occurs depending on adjustment setting values. Consequently, control points to be used are determined in accordance with a combination of density ranges to be adjusted of the plurality of density ranges. Further, a density level at an intermediate point in a density range to be adjusted is adjusted based on an adjustment level of the density range to be adjusted. Then, by performing interpolation between the control points to be used including an intermediate point whose density level is adjusted, density characteristics data indicative of density characteristics is generated and then density adjustment of image data is performed.