An image processing apparatus is provided that includes an acquisition unit configured to acquire a plurality of viewpoint images having different viewpoint; a calculation unit configured to calculate associated information associated with parallax from the plurality of viewpoint images; an image processing unit configured to generate an output image by performing an image process on image data based on the plurality of viewpoint images; a setting unit configured to set the image process using the image processing unit; and a determination unit configured to acquire the associated information, determine an effect of the image process for each area in the output image, and output the determination result.