An image processing apparatus includes: an enlarging unit that enlarges target data by using an enlargement factor based on an optimal sample number indicating a quantity of samples per unit length suitable for an image processing process; a decomposing unit that generates a group of data satisfying the optimal sample number by performing a decomposing process realized by a multi-resolution analysis on the enlarged data; a data processing unit that generates an already-processed group of data by performing the image processing process on the group of data satisfying the optimal sample number; a reconstructing unit that generates reconstructed data by performing a reconstructing process realized by a multi-resolution analysis on the already-processed group of data; and a reducing unit that reduces the reconstructed data in such a manner that the quantity of samples per unit length becomes equal to the quantity of samples per unit length in the target data.