There is provided an information processing device, which comprises a determination unit to analyze a main image and a watermark image to be added to the main image to determine an overlap part of the main image and the watermark image, a transparency adjustment unit to adjust transparency of the overlap part in the watermark image to first transparency, and an overlap processing unit to obtain an overlap image of the main image and the watermark image of which transparency is adjusted by the transparency adjustment unit by overlaying the watermark image of which transparency is adjusted on the main image.