An image pickup apparatus (100) generates a second image based on a first image obtained via an image pickup optical system, and includes an image obtaining unit (101) configured to obtain the first image, a storage unit (106) configured to store a plurality of pieces of correction information calculated for each of groups divided based on information of a deteriorated image generated by applying each of a plurality of deterioration functions to a reference image and on the plurality of deterioration functions, and an image correcting unit (105) configured to generate the second image based on the first image by using correction information selected from among the plurality of pieces of correction information depending on information of the first image and the deterioration function based on shooting condition information.