An image processing apparatus that performs a color conversion of a image expressed by coordinates of a multidimensional color space, including, a storage unit for storing lattice point data in the multidimensional color space, an address generating unit for generating addresses for reading from the storage unit the lattice point data in a first region and a second region in accordance with input values of a color signal, the first region being a region where values of all color components are equal to or larger than a first threshold, the second region being different from the first region, and an interpolating unit for generating a converted color signal by an interpolating process based on the read lattice point data. A lattice-point interval in the first region is narrower than a lattice-point interval in the second region.