Steganography is a technique to hide secret information in some other data without leaving any apparent evidence of data alternation. All of the traditional steganographic techniques have limited information-hiding capacity. They can hide only 10 percent of the data mounts of the vessel. This is because the principle of those techniques was either to replace a special part of the frequency components of the vessel image, or to replace all the least significant bits of a multi-valued image with the secret information.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.