METHOD FOR INSERTING WATERMARK THAT IS NOT AFFECTED BY IMAGE COMPRESSION AND METHOD FOR JUDGING FORGERY OF IMAGE USING THE SAME

摘要

PURPOSE: A method for inserting a watermark that is not affected by image compression and a method for judging forgery of an image using the watermark insertion method are provided to judge only whether or not there is deformation of an image without being affected by image compression. CONSTITUTION: An input image is split into the first blocks each of which has a predetermined pixel size(S220). Each of the first blocks is divided into two second blocks each of which has a predetermined pixel size, and each of the second blocks is discrete-cosine-transformed(S230). A watermark is inserted into the transformed second blocks(S250). The second blocks having the watermark are inverse-discrete-cosine- transformed(S260), to output an image into which the watermark has been inserted.