The invention is an information hiding method for the split and reversible gray value, which splits a few gray values that appear in the digital image most frequently and makes corresponding movement on the other gray values meanwhile, to generate the gray space for hiding additional data. These additional data will be placed in the gray space, where the receiver can extract data and restore the original image by inverse operation. The invention is characterized by very small changes to the vector image. The sender can hide the information effectively in the digital image, and the receiver is very easy to complete data extraction and restoration of original image. |