An image processing apparatus includes an image synthesizer configured to correct input images based on first-correction data to generate corrected images, and to generate a synthesized image by stitching the corrected images together, a determiner configured to determine whether the corrected images are appropriately stitched together in the synthesized image by using a first-trained model learned whether images are appropriately stitched together, a second-correction-data generator configured to generate second-correction data by supplying the input images to a second-trained model learned relationships between correction data used to correct source images to generate corrected images appropriately stitched together and the source images, and an image updater configured to output the synthesized image when a determination result of the determiner is affirmative and output an updated synthesized image generated by causing the image synthesizer to update the synthesized image based on the second-correction data when the determination result of the determiner is negative.