An image processing apparatus includes a memory, a scanner, and a processor configured to: control the scanner to read an image formed on a sheet along a reading direction, and store data of the read image in the memory, determine a plurality of regions of the image, select one of the regions based on a whiteness or saturation level of color thereof, and add a first image indicating the reading direction to said one of the regions, and store data of the image to which the first image has been added in the memory.