Patent ID: 8064634

Claim:
A history image generating system comprising: a determining unit that determines whether or not an image to be combined with a history image stored as history is a digital watermark image; a processing unit which, when it has been determined by the determining unit that the image is a digital watermark image, performs, with respect to the digital watermark image, processing including enhancement processing such that the visibility of the image is increased; and a generating unit that generates a composite image in which the digital watermark image with respect to which processing has been performed by the processing unit and the history image are combined; Wherein the processing by processing unit includes at least one of blur processing and mosaic processing performed by the processing unit after the enhancement processing; and wherein the determining unit determines whether or not the image is a digital watermark image on the basis of the image dimensions of the history image and the image or the percentage of a region in which pixels of a predetermined color are formed in a predetermined region of the image.