A system and method for embedding information within an input image
utilizes specific type pixel blocks of the input image to selectively
embed the information into the input image. The information is embedded
into the input image by replacing the specific type pixel blocks with
predefined dot shape blocks, which represent the information to be
embedded. In an embodiment, the specific type pixel blocks are minority
pixel blocks, which include a majority of pixels that contrast with the
image background. The use of minority pixel blocks makes the embedded
information less perceptible in the final image. In an embodiment, error
diffusion is performed on a pixel block by pixel block basis so that the
final image with the embedded information is of high quality and more
suitable for printing on laser printers.