An information generation unit 30 acquires, from a polarization imaging unit 20, observation values in which polarization directions are at least three or more directions (m≥3). A noise amount calculation unit 35-1 calculates an amount of noise on the basis of an observation value in a first polarization direction. Similarly, noise amount calculation units 35-2 to 35-m calculate amounts of noise on the basis of observation values in second to m-th polarization directions. A polarization model estimation unit 36 estimates a polarization model by using the observation values for the respective polarization directions and the amounts of noise calculated by the noise amount calculation units 35-1 to 35-m. Thus, it is possible to calculate a polarization model that is robust against noise.