Visual Data Coding Algorithms for the Problem of Steganographic Information Protection

Wide spread of digital image in every aspect of human life made them not only a part of entertainment or communication ingredient, but also an important instrument of information transfer in general. Some information must remain secret while being transferred, therefore a problem of data concealment and protection inside image appears. The method of concealment, which is based on bi-signed structural coding, and foresees the change of value of image structural signs in obedience to maintenance of secret message, is presented, so that possible intruder couldn’t even know about secret information. The offered method of hidden message concealment in a static image is realized in program using MathCAD, so it can be easily implemented using limited technical capabilities. Basic characteristics that determine the quality of concealment were defined during the investigation. The numerical values of these characteristics are calculated for a test image-container.