Patent ID: 8520264

Claim:
A method of embedding information into an image, by a computer, the method comprising: dividing, by the computer, the image into a plurality of blocks; providing a plurality of embedded blocks corresponding to the plurality of blocks, respectively, each of the embedded blocks having a same size as each of the blocks when each of the blocks is smaller than a predetermined physical fixed-size, each of the embedded blocks having the predetermined physical fixed-size and being placed at a center of each block when each of the blocks is not smaller than the predetermined physical fixed-size; and selectively modifying a characteristic value of each of the embedded blocks based on a determination as to a set size of the embedded block in accordance with the providing such that the information is embedded into the image where one of an amount of characteristic of a block at a left of an area corresponding to a size of an embedded block becomes more than an amount of characteristic of a block at a right of the area corresponding to the set size of the embedded block, and the amount of characteristic of the block at the right of the area corresponding to a size of the embedded block becomes more than the amount of characteristic of the block at the left of the area corresponding to the set size of the embedded block.