An image processing apparatus obtains an image of an original area on the basis of a platen image obtained by reading an entire surface of a platen including an original placed on the platen. The image processing apparatus extracts a plurality of image areas included in the platen image, and determines whether each of the extracted image areas has a specific characteristic. The image processing apparatus judges that a rectangular area including all of the plurality of image areas is an original image in a case where at least one of the plurality of image areas has the specific characteristic, and judges that each of the plurality of image areas is an original image in a case where none of the plurality of image areas has the specific characteristic.